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Message started by cheapnewb24 on 12/01/15 at 12:19:39

Title: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/01/15 at 12:19:39

I have really been thinking about installing a Harley muffler. That stock muffler with its iiiiittttyyy-bittty outlet can't be good on that engine, or can it? Being a musical guy, I would appreciate a good sound, but I would prefer not to have an ear-fatiguing muffler. I sometimes wear earplugs, but I don't want to feel like I have to wear them just because of the muffler. Wind noise is enough to worry about. How loud is the Harley muffler? I have listened to some of the recordings on YT. There is definitely a difference, but recordings don't say everything. What pipe diameter do I need to get? I have noticed that there is some variance in the length of these mufflers. Are the shorter ones louder? Is there any difference amongst the different mufflers.
Is the sound pleasant or a little much? How long can one listen to it without hearing fatigue? What are your experiences?

Title: Re: Harley muffler
Post by cheapnewb24 on 12/01/15 at 12:36:53

Would the muffler mod be one of the easiest ways of getting more power and longer life out of the engine? Would this be more or less effective than carburetor jetting alone? Of course, carb jetting and exhaust are interdependent. I'm just asking which is more effective than the other.

Title: Re: Harley muffler
Post by cheapnewb24 on 12/01/15 at 12:44:33

Also, is the big single more or less vulnerable to a restrictive exhaust compared to multi-cylinder engines? It would seem more vulnerable due to the sudden breathing requirement due to a single, large exhaust pulse, particularly at a relatively high engine speed for a 3.5 inch stroke. At highway speeds, the engine is turning about 4K RPM @ 60 mph, compared to an automotive engine of similar stroke length, this is insanely high. My Subaru has a stroke, I believe, of less than 3 inches, and cruises at only 2.5K @ 60 mph.

On the other hand, that one pulse has alot of time in that exhaust pipe to rest between pulses compared to a 4 cyl.

My thoughts are not quite mature on this subject, so some of this may be a little fuzzy.

Title: Re: Harley Muffler and Exhaust Theory
Post by Dave on 12/01/15 at 12:51:13

How many Monster Energy drinks have you had today....so far? :o

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/01/15 at 13:00:15

;D No Monster for me, just some coffee. Maybe I'm just ADHD or something. I've been resting my crash-injured leg playing with this forum all day. I've been worried that I'm trying to take a cold or sore throat as well.

Title: Re: Harley Muffler and Exhaust Theory
Post by Serowbot on 12/01/15 at 13:16:37

You won't see a lot of difference in power with a Harley muff, or any muff, even with jetting and intake mods... but, there is a little...
Harley muff's with baffle intact, are not loud, but pleasantly deeper, and less like a sewing machine.
Plus, they will save you 6 to 8 pounds and look better...

Well worth the trouble, but don't expect miracles... 8-)...
The power gained is more psychological then anything... (better sound, feels more powerful)...

This, is a link...->Harley Muffler Guide (http://suzukisavage.com/cgi-bin/YaBB.pl?num=1298689417)

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/01/15 at 13:27:26

I would say that the greatest difference will be noticeable at interstate speeds/mid-high rpm under high throttle, where a restrictive system may run short on breath.

Will the savage run substantially cooler with the Harley muffler?

Title: Re: Harley Muffler and Exhaust Theory
Post by Kris01 on 12/01/15 at 17:03:29

I think you may be reading too much into this. The Harley muffler just gives a slightly louder deeper tone. It's lighter weight as well. They don't give much hp, if any.

Title: Re: Harley Muffler and Exhaust Theory
Post by raydawg on 12/01/15 at 17:20:00

Yeah this bike is what it is, and nothing more.
You want to make it something it really isn't, then you might just look at another bike to satisfy your biking mindset.

The Harley clamp-on Dyna's that I am sure Bot provided in that link work real well. It does not come off as a poser, just takes the tinny away.
Also, don't put too much stock in the tailpipe diameter, as the baffles are what restrict the flow more than the opening anyway..

Title: Re: Harley Muffler and Exhaust Theory
Post by Blade on 12/01/15 at 23:40:22

I bought my Savage from an older gent who also had an Enfield. At some point he had put an Enfield muffler on the LS, and I'm glad he did. Nice note (most people think it's a Harley) but not too loud.

I'll put on a pic.

Title: Re: Harley Muffler and Exhaust Theory
Post by Blade on 12/02/15 at 02:13:16

Enfield muffler

Title: Re: Harley Muffler and Exhaust Theory
Post by justin_o_guy2 on 12/02/15 at 08:38:25

I wish I knew how to change the darkness of the print Ohhh, lookie right up THERE! Gosh I'm so dumb,,

I would like to see someoneDaveswap mufflers and run either time trial tests or Dyno.
Whether the Dyna improves the Dyno HP or not, it loses pounds, looks So Much better, and sounds So much better, and the Stock mufflers sound like a VW, and whistle.
No, allowing it to exhale won't
Unleash the Beast
but it's a step forward in every way.

Intake theory, everyone is focused on exhaust, and, it's important, but when it is inhaling, no piston is positively displacing the gases. The design of the intake , IMO, matters.

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 08:50:46

Interesting on the Enfield muffler. I love Enfields, but there aren't very many around here, at least as far as dealers are concerned. I met a girl (a newb like me, even more so) riding a military green Enfield. She needed help starting it, but I didn't get that opportunity. I wish she would have let me kick start it :D. Those things are cool, hers had saddlebags almost like ammo cans, she had a front drum brake, which is Oh so cool on a 2008 :o. The funny thing is that it sounded substantially quieter than mine :-? Maybe its just where I was on mine and she on hers. :-?

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 08:57:57

On Exhaust theory, the engine can't intake if it can't exhaust properly.

On the intake, would you suggest that the air filter was undersized for the big single 650 application? Some say that paper filters best and the difference in breathing is not much worse than foam and cotton. I read about someone who experimented with it. If I can find the site again, I'll post the link.

I would say that paper would probably be best, provided a large enough air box. If the air box is substantially undersized (too small an air filter), then the cotton/foam filters might make a greater difference.

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 09:00:19

57484E4954536252625A48440F3D0 wrote:

Intake theory, everyone is focused on exhaust, and, it's important, but when it is inhaling, no piston is positively displacing the gases. The design of the intake , IMO, matters.

Are you saying that the big single never gets a full charge of fresh air under normal conditions, or any conditions?

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 09:16:22

"So what do these results mean? For one, there is very little pressure drop across any air filter, and the difference between the best (K&N) and worst (paper) is very small. Yes as total power output increases, air flow increases, and differential pressure would also increase. So a K&N probably does yield some power on higher output race motors where every last ounce of power must be squeezed out. On lower powered street cars, it is probably not much of an improvement over paper. "

--BobIsTheOilGuy

http://www.bobistheoilguy.com/airfilter/airtest2.htm

He has other test results, such as filtering performance, on separate pages

That's why I asked whether the filter is undersized, because, if it were undersized, then the restriction of different filters would probably matter more.

Title: Re: Harley Muffler and Exhaust Theory
Post by Dave on 12/02/15 at 09:51:26

In some respects, an engine is similar to an air pump. The air going in is combined with fuel, and then it has to go out. When the bike comes for the factory the in/out flow is designed pretty equally, and on modern bikes both the intake and exhaust side are made to be pretty quiet. The air box/filter/snorkel all work to keep the sound in and rain out....the muffler is designed to keep the loud portion of the sound in, and to dampen pressure waves that can decrease performance.

If you are not doing anything inside the engine to increase performance (bigger piston, higher compression, more cam, porting), then you aren't going to get very much gain by changing the muffler or air filter....or even the carb. The cylinder head does not have a very good exhaust port design, the header is a bit restrictive...but it all works to make a decent running bike - youzguyz has proven the engine can go 140,000+ miles with normal maintenance.

There isn't much to be gained by taking out the paper element and putting in a foam or gauze filter. Changing to a cone filter on the end of the carb most likely will runs worse than the stock air box and filter as they are generally very small and provide a turbulent flow that the CV carb finds confusing. Removing the snorkel or drilling holes in the airbox....I remember seeing where someone took pressure/vacuum readings and couldn't detect any change....the snorkel helps to cut down on the intake sound and keep water out of the air box.

Changing to a DYNA muffler saves some pounds, looks better, sounds better....it is a worthwhile change even if the performance doesn't increase. I don't believe the engine runs any cooler with a DYNA....the exhaust flows through both mufflers as fast as the engine spits it out, and I can't see how a little more or less pressure in the header changes the heat output of the engine. At normal cruising speeds either muffler has plenty of flow ability, and how many of us can go at full throttle for more than half a minute?

Changing the stock carb to a round slide Mikuni on a stock engine won't increase the HP - it does change the response by allowing the engine to respond just a bit quicker to throttle changes. It does however become far more sensitive to those with too heavy of throttle hands, and you need to learn to roll the throttle on/off and not "whack" the throttle open or closed.

If you do start to make internal engine changes for more performance (piston, cam, head porting), then changing the intake (carb, filter) and exhaust systems (header, muffler) becomes more necessary.

For a year I rode my bike with the stock paper air filter, stock carb, Wiseco 95mm piston, Stage 1 cam, stock header and a DYNA muffler. It was a great running engine and had significantly more power than a stock engine. It could still get 50-60 mpg depending on how I chose to ride....the only downside is the swiitch to Premium fuel. Later I changed to a Mikuni Roundslide carb and although I don't know if the top speed increased any - the throttle was just a bit more responsive and the bike reacted just a smidge faster when you moved the throttle.

So.....it is my opinion that for most folks adding a DYNA muffler and making sure the carb jetting is correct is about all you need to do to a stock bike. You don't need an expensive cotton gauze air filter, you don't need Kevlar clutch plates, you don't need a Mikuni (unless your stock CV carb is broken), and you will still have a very good running Savage. Even a "highly" hopped up Savage engine is going to lose a drag race with any 400cc sport bike unless you keep the race very short.....like across the intersection!

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 10:08:04

Hmmm... If the Dyna muffler requires a rejet to a larger size, then, it probably is increasing flow. If flow is greater, then backpressure is less and EGT's are lower, and maybe the heat is also getting out of the engine a just little faster, making it run a little cooler.

Now, this may not be a very big difference, but it seems reasonable that it would help, don't you think? Am I mistaken?

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 10:09:53

By the way, my exhaust pipe has turned dark blue near the engine. I remember reading here that it is from running too lean/hot.

Title: Re: Harley Muffler and Exhaust Theory
Post by Dave on 12/02/15 at 10:29:54

565D5054455B5042570701350 wrote:

I think you are overthinking most of this.

The Savage is jetted too lean for good performance from the factory. The jetting is set up to reduce emissions as much as possible, and a lot of bikes have some surging and lean conditions. My jetting recommendation was so you could get your bike running as well as possible. The stock jetting sometimes works well for bikes that are being used at higher elevations where the thinner air solves the lean mixture issues. The ideal fuel mixture for mileage and emissions is 14.7 parts air to fuel....and for the best performance the mixture is a bit richer at 13 parts air to fuel, and the richer mixture makes the bike run smoother and perform better.

So....my suggestion for conforming you jetting is correct, applies to the stock and DYNA muffler.....or any muffler you put on.

Can you provide and link to a reputable test that shows that a muffler swap can allow an engine to run cooler? I have looked, and I haven't found any. I wouldn't trust information provided by anyone that sells the new muffler or exhaust - something that in independent testing agency or magazine has done? Folks assume that a free flowing exhaust somehow allows the exhaust to leave faster -but it doesn't as the exhaust will leave the muffler tip at the same rate. The only difference I can see as a factor would be that the lower pressure in the exhaust system would be slightly less dense exhaust gasses, and that may allow the header to lose a degree or two - but not the engine.

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 11:15:49

Is the factory jetting around 14.7 A/F ratio, or is it significantly leaner? Is all the rejetting used to make the bike run richer than stoichiometric?

Title: Re: Harley Muffler and Exhaust Theory
Post by Dave on 12/02/15 at 11:26:51

22292420312F2436237375410 wrote:

Is the factory jetting around 14.7 A/F ratio, or is it significantly leaner? Is all the rejetting used to make the bike run richer than stoichiometric?

There is no way to know for sure....it is not a computer controlled device that can adapt to changing environments. Every bike runs a bit different, every bike is run at a different altitude, and the fuels around the country (world) are not all the same. Pure gasoline, E10 and reformulated fuels don't run the same, temperature, humidity and air pressure change constantly. You just need to jet the bike so it runs right for where you ride.....and it most likely won't be perfect for all conditions. When we go ride in Tennessee we can ride through 4,000 feet of elevation change.....and the Fuel Injected bikes will make changes to the fuel flow rate....we cannot.

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 12:22:18

Yeah, but what about at sea level at room temperature and average humidity with regular non-ethanol gas? The question is this: is it set factory lean or factory stoichiometric under the typical test conditions like the factory or EPA would use? In other words, the "official" A/F specs? I typically ride somewhere around 1000 and 2000 feet elevation, so I shouldn't have as much of a problem as the lowlanders.

Also, how can one tell when they've hit stoichiometric? Is it the point where the engine runs the fastest under the least throttle (for idle mixture anyway), or is that slightly rich? Slightly lean? When it is said that more power can be gotten from a rich mixture, is that a consequence of less knocking, smoother power, and more torque, not higher speed with less throttle? Is high speed with less throttle a little lean? Does the most powerful mixture (rich) actually decrease engine speed a bit relative to throttle, but increase torque?
I've researched some of this before. I read that the idle mixture is supposed to be right with the highest vacuum (highest speed with least throttle). I've read some of the guides here on mixture tuning. I'm kinda asking for your opinion, or clarification on this.

Title: Re: Harley Muffler and Exhaust Theory
Post by Dave on 12/02/15 at 12:38:56

OK...you win. I give up. :-?

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 12:50:56

As Serobot mentioned in his tuning guide, pulling the enrichment knob increases the engine speed. For me, 1 click will do it, and that is often enough to start the engine when its a little chilly. It's like the perfect setting or something, though I can't say about mileage or emissions. Furthermore, if I'm not careful, pushing the knob back in will very easily stall the engine at idle. I think it even runs faster when warm with this setting, although a good run during the heat of summer would better test that idea. I guess that means I should do the white spacer mod? I have been aware of this for a while, but reading it again today seems more clear. The article in the following thread seems to be the source for the idea that the carb is jetted very lean http://suzukisavage.com/cgi-bin/YaBB.pl?num=1104205157
Do you think the author of this article is correct?

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 12:56:03

I guess I should give up too, but not before I show you this :D

http://suzukisavage.com/cgi-bin/YaBB.pl?num=1185590369

http://img.photobucket.com/albums/v124/Odar1/Odars%20Savage/Dynobeforeafter.jpg

If none of the simple mods make much difference, then what the heck is this? ;) Dyno error? User error? Unexplainable?

Note that the shape of the curve changes as well as the height. There is a noticeable improvement in the torque curve above 3500 rpm. This may be due to better breathing. Of course, it could also have something to do with fuel delivery or some other thing.

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 13:05:25

But then, now that I look at it, it seems that the mods only give you back the power that the bike was supposed to have in the first place!
Its like Suzuki sold us the horsepower and the EPA stole it before it even left the factory :P.

Title: Re: Harley Muffler and Exhaust Theory
Post by Dave on 12/02/15 at 13:07:12

A proper running bike should have been up near 30 HP without any modifications.....so the bike may have needed better jetting or had a dirty carb when the initial 25 HP run was made. When the new jets were installed for the Raask, the jetting was probably adjusted to work with the new pipe and muffler. The Raask includes a larger header pipe......so it is not just a muffler change.

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 13:07:21

Wait a minute... No, that's still more hp than factory rated, isn't it?

I was referring to my own comments before I saw yours.

Also, a larger header pipe would give more buffer space for the gas to reside between pulses, important for a big single. But then, wouldn't a larger pipe increase back pressure according to Bernoulli's principle, or some such law. I gather that smaller pipes can actually reduce backpressure by increasing gas velocity, which, physics-wise, actually reduces pressure ::) That all assumes no friction, I guess. I'm most certainly not a physics pro, in case I sound like it. ;)

Overthinking it, am I? ::)

I'm like the Energizer Bunny of the Suzuki Savage forum: I just keep going--- and going--- and going ;D

Title: Re: Harley Muffler and Exhaust Theory
Post by Struch on 12/02/15 at 13:24:48

I have to do sam tuning on my carb wen I install OEM Harley muff

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 13:29:15

1 click on the enrichment knob increases rpm with the stock muffler. Just think how lean it would be with the Harley muffler? To beat all, I have already adjusted the idle screw. How worse would it be with the Harley muffler, factory jet, and factory idle settings? :o

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 14:03:31

From what I've seen so far on YT, the Raask exhaust is a dragpipe. How come there is no mid-range loss on the dyno test I referenced? Is the idea of midrange loss with dragpipes flawed, or are big singles immune to this? Are the rpms to low to cause the effect? Am I missing something here?

Title: Re: Harley Muffler and Exhaust Theory
Post by Dave on 12/02/15 at 14:08:00

666D6064756B6072673731050 wrote:

1 click on the enrichment knob increases rpm with the stock muffler.

If you are moving the enrichment knob when the bike has just been started and is not fully warmed up....that increase in speed at one click is to be expected. When up to full temperature the bike should slow down when you pull out the enrichment knob if the carb is clean, and the fuel mixture screw has been properly adjusted.

There will no noticeable difference of the fuel mixture at idle if you change the muffler....the engine is not working hard enough to build up any pressure in exhaust system.

Title: Re: Harley Muffler and Exhaust Theory
Post by justin_o_guy2 on 12/02/15 at 14:12:48

You know that I at RPM, there is a gulp, stop,gulp,stop,of air running through the carb. You're all familiar with the
Suck on a skinny straw in a malt
thing.
What I've read said that the volume of the air box, behind the filter, needs to be at least as big as the gulp. Now, IF the intake was designed to allow for a moving column of air to be set up so that the moving column was approaching the carb at the same time as it was ready for that gulp of air, then the cylinder would get a better charge. That would be pretty RPM range limited potential positive power boost, and, again, it's not gonna just unleash the Beast, because it's not gonna Be a beast, but, I believe that if someone wants to drag everything out of what it can be, then there is a potential idea. I did increase the volume of my air box, but, I didn't test anything beforehand, I didn't do any mods scientifically and I can't prove anything, any One thing, did X increase in performance.
IIRC, I did the cam, carb, exhaust and air box all at the same time.
I got really close to six second zero to sixty times, maybe even Did, it's hard to ride and time stuff.. And after I hit second, it was just throttle and shift, when the rate of acceleration started to taper off, I'd grab a gear.
The innerneck is a Huge library. It's NOT all porn. Intake manifold theory is out there.
I should've done some exhaust work on the head.
I'm Not saying the time spent on exhaust system flow isn't smart.
Pulses of air are moving down the pipe, ideally, having a pulse leaving and creating a low pressure event in the pipe to make exhaust gasses have a place to go reduces the power required to Shove them out.
Again, That ideal moment would be most effective in a limited RPM range. It would take a smart guy to actually design that stuff and the potential gains are likely not even close to worth the effort.
We have guys who have proven certain things and are getting the performance that the frame geometry, brakes, everything, will really deal with. It's not a beast, but, it will Whoop it across town and zip through traffic and look and sound good with just an exhaust system and a cam. Including in that,
The cheapest and most effective immediately realized power gain is losing weight.

I Wish I had done it scientifically.. I regret that .

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 15:28:59

I bet that if there is a change to be made in the main jet, I will only notice it after adjusting the needle jet. That's why I am not noticing a problem with the main jet.

Title: Re: Harley Muffler and Exhaust Theory
Post by Kris01 on 12/02/15 at 17:47:22

Apparently you've read the carb tuning guide. Just tune the bike to run well and enjoy it. That's all you can really hope for. Who cares what the A/F ratio is or even if it's at stoichiometric. You can tell by how the bike runs. Just jet it like the tuning guide says. Once it stops surging at speed you can probably stop jetting richer.

Or.....
Go to a shop with a dyno and tune with that. Dave tuned his with an AFR gauge and got real close to what everyone else was doing. In other words, tune it by ear (or seat of the pants) and you're golden!

;)

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/02/15 at 19:01:10

Wouldn't high speed surging be the case when you're going down the road and you feel this ever so slight jerking? You might try to pass it off as little bumps in the road, and say to yourself that maybe it's just the crappy suspension. Am I hitting the nail on the head?

Title: Re: Harley Muffler and Exhaust Theory
Post by Dave on 12/03/15 at 05:30:34

Surging is not something that happens quickly....it won't feel like bumps in the road. It feels more like when you are pulling a heavy trailer behind a car and the trailer tends to push and pull on the car and it varies the acceleration rate. It also feels similar to when you are riding in a car with someone else driving....and they just aren't sure if they want to pass that semi truck, and they keep putting their foot on/off the gas pedal a bit while they are trying to make up their mind about passing.

Most bikes have a #145 main jet from the factory, and this generally isn't so lean that any surging will occur under full throttle.

The early bikes had a #47.5 Pilot Jet, and this can be a bit lean, and the later bikes had a #52.5 Pilot Jet - which is plenty rich.

The big problem with the stock carb setup is the slide needle. The mixture is just too lean when you first start to open the throttle, and several of the bikes I have ridden with the stock jets have a surge when you just start to open the throttle. When you are riding behind a mini-van in town, or riding past a Police car and riding at a calm rate at low throttle settings......the bike will surge a bit as you shift gears and just open the throttle a little bit. If you apply a lot of throttle and the get the carb to raise the slide and needle - generally the surging goes away and the bike accelerates smoothly. The fix for this condition is to remove the stock white spacer and replace it with some #4 machine screw washers....generally 3 works well, for my bikes I still had a slight bit of surge and went to 2 washers and had better luck.

I am not going to get into a long discussion about fuel/air ratios, stoichiometry, etc......but if you want to jet your bike correctly, here is what you do.

The first thing to do is start with a clean carb, there is no reason to try and jet a carb that is dirty, it is a waste of time. It is also necessary to remove the brass plug over the idle fuel mix screw, and you will need to remove this when you clean the carb and for future adjustments.

The next thing to do is start with some jet sizes that are known to work. I would start with a #150 main jet, and a #50 pilot jet at your elevation, and 3 washers on top of the slide.

You start by setting the pilot jet....the side of the main jet and the height of the slide needle have no affect on the pilot jet. When you have found a pilot jet size that works, you won't have to change it when you are adjusting the other jet sizes. Start with a #50 pilot jet and then set the idle fuel mix screw out 1.5 - 2 turns from lightly seated. Then start and warm the bike up....adjust the screw as shown in the attached video links (The Savage carb has a fuel screw....not an air screw):

https://www.youtube.com/watch?v=YxpQjDQzX7g

https://www.youtube.com/watch?v=zm5mB3R8Ucw

For the Savage CV carb you want the screw to be at 1.5 - 2 turns out. If the bike runs best at less than 1.5 turns (or if you can turn the screw all the way in and the engine still runs)....the pilot jet is too big and you need to put in a smaller one. If the screw requires more than 2 turns out, you need a larger pilot jet. (There is no reason to ever turn the screw out more than 3 turns, as the tapered needle is so far out of the hole that no additional fuel will flow if you go out any farther).

Once the Pilot jet and air screw are set - you can go for a ride and see if the main jet is correct. You need to find a long stretch of road, and uphill straight is best as it helps to limit the speed and acceleration a bit. You want to be in high gear and at about 40 mph roll the throttle open all the way and hang on......and the bike should be accelerating smoothly. If you roll the throttle off slightly and for an instant the bike feels like it runs better - that is an indication the jet is too big. If you feel surging, that it an indication the jet is too small. Ideally you keep changing jets and find out which smaller one causes surging and which jet makes the bike too rich - then pick something in between. I suspect that the #150 is going to run just fine with either the stock or DYNA muffler.

The next thing to set is the slide height. Put a piece of tape on the throttle grip, and then make marks for full, 1/2, 1/4 and 1/8th open positions. Go for a ride and warm the bike up, and then go through the gears while opening the throttle up about 1/8th throttle. If you feel any surging at light throttle settings, then you need to raise the needle by removing one of the washers. Most folks are fine with 3 of the #4 machine screw washers, at my 500 - 800 feet elevation I have had better luck with just 2 washers. If you get it too rich the bike become a bit sluggish at light throttle, and makes funny burble sounds when you let off the throttle a little bit. You want to use enough washers to let the bike accelerate smoothly....don't remove too many or the bike will run too rich and get crappy fuel mileage.

So....that is how you adjust a carb on the Savage. Look in the Tech Section on Carb cleaning if you need to, buy some Allen Screws for the carb so you can remove the float bowl to change jets with the carb still mounted on the bike, order some jets and a float bowl gasket from Lancer so you have a selection to use, and go at it. If your bike currently shows no signs of running poorly or surging......you may not need to do any of this as some folks have no problem with the stock jetting (higher altitudes are best for the stock jetting).

Title: Re: Harley Muffler and Exhaust Theory
Post by justin_o_guy2 on 12/03/15 at 06:11:15

Dave, if you didn't read my post, I wish you would. Tell me what,if anything, I have right, wrong, if wrong, why.

Also, I did dissect the header and removed the inner pipe, then had the chromed exterior pipe tigged together. The welder and I got along so well, I put stuff up in his shop, and he charged me zero.

Title: Re: Harley Muffler and Exhaust Theory
Post by Dave on 12/03/15 at 07:34:17

647B7D7A6760516151697B773C0E0 wrote:

Dave, if you didn't read my post, I wish you would. Tell me what,if anything, I have right, wrong, if wrong, why.

JOG....nothing wrong with what you wrote. I posted what is necessary to jet a stock bike (or bike with muffler swap). It was not my intent to create a post on engine upgrades.

cheapnewb24 posted this a month ago:

"I am new to motorcycling. I took the MSF Basic course and got my license about a month ago. I got an '04 Savage for locally for $1K as my first bike."

So he has been riding with a license for a couple months. I really believe he needs to get his bike running well, fix up the parts he broke in his crash a few days ago, and then go out and ride for a while and get some experience and become a competent rider before he starts to be concerned about Kevlar clutch plates, drag pipe exhaust reversion, or modifying the air box for ultimate flow.

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/03/15 at 12:09:40

Alright, that's it! I have a few things to say here. This reminds me of my Dad who helped me buy our 83 Shadow. He kept buying stuff like windshields and saddlebags for it. I just wanted him to just keep it naked and ride it. The idea was that I would pay for part and he would pay the other part. Eventually, it got to the point that I wanted to pay my half in order to keep him from messing with the bike. For that reason, amongst others, he decided to put the bike in his name and not let me pay for it. Funny thing is that he doesn't even have his learner's permit yet, much less his license, and he's in his mid 60's ::).

Anyway, now the shoe is on the other foot. I am entertaining the idea of tinkering and talking about physics and theory, you know, all that interesting stuff, and now I am being told, especially by Dave, to just forget about it and ride. Do x, y, and z, and ride--- we're not going to talk about the rest. Well... considering that I have been laying around the house with a cold recovering from my mildly injured knee in the mildly chilly, wet November weather, does it surprise you that I am not riding? For goodness sakes, I just learned that I am off from work over this cold. I work at a restaurant, and I am not allowed to work with a contagious disease. Ehhh... What the heck, I was only going to work 2 days this week anyway. I usually get 3 days and around 10 hours per week anyway, and that's at minimum wage. Yeah, It sucks. :P

The point is that thinking about tinkering and theory is kinda fun and keeps the boredom away. I'm used to it. I have considered mechanical engineering often because of it. It's also encouraging to think that there is something to be done to my bike. If it was all said and done, wouldn't that be a bit boring? If you are wondering why I ask so many questions, it is because that is my nature. When I was in college, I used to ask a lot of questions, even to the point of tiring the professors and annoying the students. To beat all, many of my questions were not on the test, if you know what I mean. ;) I guess I liked learning or something of that sort.

This is a forum, where people talk about stuff. If anything, I would think that I would help keep this forum alive. I'm sorry if I am a problem here.

Furthermore, there are certain reasons I ask some of the questions I do. First, with A/F ratios, I want my bike at its optimum. I don't really want to go around polluting the environment and getting crappy gas mileage just to squeeze that extra bit of torque from running rich. That's why I asked that question. As far as Kevlar clutches are concerned, you need to understand my situation. For one thing, the Savage clutch, as we all know, is naturally weak and prone to occasional slippage. For another thing, I will need to open the case sometime soon in order to replace the bad neutral switch, which I have lived with so far. The most important thing that I must do is check the cam chain tensioner to make sure the engine is not preparing to grenade itself :o. While I have the exhaust off and the case open, I have the opportunity to work on the clutch. I can either shim it, put in extra plates, kevlar it, change the rod, do something else, or do nothing at all.

I appreciate your take on carb tuning, It's not quite the same old stuff. Some good ideas, like the Allen screws. Those Phillips screws can sure be a pain.

As far as surging is concerned, when its good and warm, I don't notice much of a problem. I assume surging is that "Oh no, I'm running out of gas" feeling. Ya might call it "missing"? Or am I mistaken?

What you describe reminds me of what I call "lurching," where you have a manual transmission machine (car, bike, or whatever) with a short stroke and very short gearing that yanks you back and forth in the lower gears (or med-high gears in low speed machines). I don't think the Savage ever has that problem with the nature of its engine and its gearing. Those little 250s, though, lurch like the dickens, even the EFI ones. Even my EFI Subaru can do that :P Gas engines in general seem terrible for it. Diesels don't seem quite as bad for it. Maybe it's the heavier flywheel smoothing things out?

There is the idea put out sometimes that one needs a lower first gear for low speed maneuvers. Turns out that when you get short gearing like that the 250 class uses, you're slipping the clutch just to keep it from jerking you around. Whereas the bigger bikes use the friction zone to slow down and stay smooth. There's really no escape from the friction zone. Of course, that's a discussion for another thread.

Before I joined this forum, I was a lurker. I would visit various forums to gather opinions on various things, but I would never join them. If I remember correctly, I found this forum and went through some of the threads before I ever bought my Savage. If I wanted to go through the same ol'--same ol'. I could have simply read what was already posted. Now there was a particular reason why I joined this forum-- I was having a technical problem and needed help-- but I have found this forum to be pretty fun :). There are times when I can't wait to see the next reply :).
Not wanting to talk about things is a bad sign for a forum. Eventually, people will decide there is nothing left worthwhile to talk about, and then the forum will die :(. Imagine, nothin' left but a bunch of decade old threads about a simple little motorcycle that was all said and done ;).

Now, if I'm wasting everyone's time and missing an experiential learning lesson by not just guessing at everything-- if I'm just beating a dead horse-- maybe I should just take what I know and just tinker with it and waste money until I figure something out. After all, that's the old fashioned way ;). Maybe I'm spoiling all the fun by asking for others' opinions. Maybe I should have done it all by myself :P :D

Makes me wonder sometimes, if you know what I mean ::)

Title: Re: Harley Muffler and Exhaust Theory
Post by chzeckmate on 12/03/15 at 12:11:08

All the science in the world isn't going to tell you what it feels like. Adding a performance muffler and rejetting accordingly will definitely deliver more HP, but not enough in my opinion, to put this much thought into it. The rule of thumb is, you need to gain 10% or more HP in order to really make any real difference. A new muffler and jets will certainly not deliver 10%. You're not going to even come close until you start looking at mechanical parts (cam, piston, etc). If you're thinking about that stuff you're either a garage warrior who just loves digging in, or you've got the wrong bike. New muffler and jets is more of a visceral improvement than anything else, but that's really more important than anything else in my opinion.

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/03/15 at 12:32:27

0E35382F3E32292F343C312E5D0 wrote:

[quote author=647B7D7A6760516151697B773C0E0 link=1449001180/30#38 date=1449151875]Dave, if you didn't read my post, I wish you would. Tell me what,if anything, I have right, wrong, if wrong, why.

JOG....nothing wrong with what you wrote. I posted what is necessary to jet a stock bike (or bike with muffler swap). It was not my intent to create a post on engine upgrades.

cheapnewb24 posted this a month ago:

"I am new to motorcycling. I took the MSF Basic course and got my license about a month ago. I got an '04 Savage for locally for $1K as my first bike."

So he has been riding with a license for a couple months. I really believe he needs to get his bike running well, fix up the parts he broke in his crash a few days ago, and then go out and ride for a while and get some experience and become a competent rider before he starts to be concerned about Kevlar clutch plates, drag pipe exhaust reversion, or modifying the air box for ultimate flow.

[/quote]

Nobody has really tried to explain why the fellow with the Raask drag pipe didn't have a mid-range dip in his torque curve. ;) I'm waiting... 8-)

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/03/15 at 12:41:30

192620273A3D15530 wrote:

You're saying that there will be a noticeable difference in the feel of the bike even though it doesn't show much on a dyno, and that some of the difference will never really be measured powerwise?

FYI, the shop I talked to doesn't even like running his dyno off-season, so I doubt that would even be part of the equation at the moment. Has something to do with running it in typical riding conditions. Well, that probably doesn't mean that I couldn't persuade him to do it anyway. The last time I spoke with him, the dyno wasn't really available. I have never even used a dyno before. That would probably be fun, wouldn't it?

Title: Re: Harley Muffler and Exhaust Theory
Post by Dave on 12/03/15 at 12:50:51

262D2024352B2032277771450 wrote:

Nobody has really tried to explain why the fellow with the Raask drag pipe didn't have a mid-range dip in his torque curve. ;) I'm waiting... 8-)

Hate to keep you waiting.

Maybe that sag in the HP curve at 3,750 is the mid range dip.

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/03/15 at 13:02:40

566D6077666A71776C646976050 wrote:

[quote author=262D2024352B2032277771450 link=1449001180/30#42 date=1449174747]
Nobody has really tried to explain why the fellow with the Raask drag pipe didn't have a mid-range dip in his torque curve. ;) I'm waiting... 8-)

Hate to keep you waiting.

Maybe that sag in the HP curve at 3,750 is the mid range dip.[/quote]

Hmmm... maybe. I originally took it as a midrange bump rather than a dip. Doesn't seem too bad for a drag pipe dip compared to what I remember on that drag pipe bashing video. Maybe he stuck some good baffles in it, or the big single is not as vulnerable to it for some reason.
Isn't there a point in the midrange where there is sometimes an extra torque boost due to the exhaust pulses working to the engine's advantage, or something like that? Like I said, I took it as a bump rather than a dip. I may be wrong, though; it could be a dip. Not trying to stretch out an argument here.

Title: Re: Harley Muffler and Exhaust Theory
Post by chzeckmate on 12/03/15 at 13:19:20

73787571607E7567722224100 wrote:

[quote author=192620273A3D15530 link=1449001180/30#41 date=1449173468]All the science in the world isn't going to tell you what it feels like. Adding a performance muffler and rejetting accordingly will definitely deliver more HP, but not enough in my opinion, to put this much thought into it. The rule of thumb is, you need to gain 10% or more HP in order to really make any real difference. A new muffler and jets will certainly not deliver 10%. You're not going to even come close until you start looking at mechanical parts (cam, piston, etc). If you're thinking about that stuff you're either a garage warrior who just loves digging in, or you've got the wrong bike. New muffler and jets is more of a visceral improvement than anything else, but that's really more important than anything else in my opinion.

You're saying that there will be a noticeable difference in the feel of the bike even though it doesn't show much on a dyno, and that some of the difference will never really be measured powerwise?
[/quote]

Yep, that's exactly right. If you put on a performance muffler and rejet, you won't regret it. The whole experience is very different and the dyno just can't measure awesomeness.

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/03/15 at 14:06:25

Well, I just went out and rode my Savage to get the mail. Kinda refreshing, though just slightly unnerving. The mud was really slippery and the weather chilly, and my skill going cold. I am also not in the best mood for finding myself and the bike rubber side up, lying in the mud. :P Didn't crash though, in case you're wondering. ;) Took more than one click on the enrichment to crank on this chilly day.

Title: Re: Harley Muffler and Exhaust Theory
Post by Serowbot on 12/03/15 at 16:40:49

That dyno chart don't look kosher... hp/torque should always be equal at 5252 rpm...

HP = (RPM* TRQ)/5252

Title: Re: Harley Muffler and Exhaust Theory
Post by cheapnewb24 on 12/03/15 at 17:10:39

I plugged the numbers roughly. It doesn't seem too far off. What have you found? Somewhere around 5252 on the graph, the torque is a little under 45 Nm or 44.5 Nm, which is a little less than 33 ft lbs. The HP at that point is a little less than the max of 33 HP, so I would say it is reasonably close.

Title: Re: Harley Muffler and Exhaust Theory
Post by Serowbot on 12/03/15 at 17:29:16

Nm's threw me... ;D...

Title: Re: Harley Muffler and Exhaust Theory
Post by engineer on 12/03/15 at 18:41:49

Dave took the time to type out a very useful procedure in this thread for tuning the stock carb and I appreciate the effort he puts into this forum. I cut and pasted it into a folder of useful Savage reference material that I keep on this computer. I have a folder for each vehicle I own. My bike runs fine but someday I might get energetic and want to tweak it a little more and Dave's short but thorough guide will be handy.

To cheapnewb I say keep on asking the questions. Your desire to optimize your bike's performance is understandable. Keep reading, asking, discussing and tinkering.