|
SuzukiSavage.com
/cgi-bin/YaBB.pl General Category >> Rubber Side Down! >> S40 Backfiring- Do I really need to fix it? /cgi-bin/YaBB.pl?num=1464287237 Message started by Fahad on 05/26/16 at 11:27:17 |
|
Title: S40 Backfiring- Do I really need to fix it? Post by Fahad on 05/26/16 at 11:27:17 Hi Guys, I just bought an S40 2005. The person I got it from also mentioned it to me while selling it but I have actually experienced it the other day while trying to slow down from 50mph in traffic. The question is, am I causing any harm to the engine or bike if it keeps backfiring and do I need to fix it rightaway. I am really not bothered by the sound and like someone said in one of these forums, it keeps people from tailgating, so I really don't mind it. Can I still continue riding? |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by oldNslow on 05/26/16 at 11:43:12 Quote:
Yes Quote:
No. In,fact you don't need to fix it ever if it doesn't bother you and you don't want to bother. There are things you can do to minimize it, and I'm sure folks will be along shortly with suggestions about how to do that. |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by Armen on 05/26/16 at 11:46:13 If the bike is backfiring on trailing throttle (which a lot of pollution era carb bikes do), it usually means it's running lean on the idle and low end circuit. I've seen a bunch of Savages that ran so hot they blued the head pipe all the way under the engine. Keeping in mind that the bikes use a double wall header pipe (think Thermos bottle type insulation), it means the bike is running crazy hot. Really not a good thing for the engine. On a lot of bikes, my fix has been to unscrew the idle mixture screw 1/2 turn (often a blanking plug needs to be drilled out) and to shim the slide needle. A simple thin washer works fine, no need for a full jet kit. The bike will be faster and more responsive, and run cooler and longer. -Armen |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by Dave on 05/26/16 at 11:52:01 If your bike has the stock jetting - it could be running lean as Armen has suggested. A change of jets might help your situation. The engine backfires when you close the throttle fully while the engine is at speeds higher than idle. The engine is trying to suck in a lot of air - but the closed throttle only allows a mall amount of fuel to flow. The fuel/air mixture in the engine becomes so lean the spark plug cannot get the mixture to burn - but when the unburned mixture goes into the hot exhaust pipe....it ignites and makes a racket. You can cut down on the noise by holding the throttle open just a crack....which allows a bit more fuel to flow. If you don't let the throttle close completely shut as you shift gears - you won't get the noise between shifts. If you hold the throttle open just a bit when slowing down....you won't get the noise (or you will get less noise). You don't have to open the throttle far enough that the bike wants to accelerate.....just enough to make the noise go away. It is all part of the charm of riding a big single! |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by Fahad on 05/26/16 at 12:07:02 Armen, The pipe is already half blue. I was thinking about commuting to work on it which is about 20 miles on the highway, do you think I should hold off until I get it fixed? |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by verslagen1 on 05/26/16 at 12:11:33 Check for leaks at the head and muffler, those will cause backfires too. a leak will blow the flame of a lit candle around or smoke. |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by Dave on 05/26/16 at 12:14:01 A blue pipe on a Savage is not a sign of doom. The bluing occurs when the chrome gets hot.....bikes that spend a lot of time in traffic are more prone to the bluing that bikes that are run on the highway a lot. A lean mixture can cause the pipe to blue - but that alone is not a sign of any damaging condition. If the bike accelerates smoothly, and does not have hesitation or bucking or flat spots when you open the throttle slowly - chances are the bike is not running so lean to cause any problems. I wouldn't stop riding the bike just because your pipe is blue. What elevation do you live? Does your bike have the stock muffler and air cleaner? How many miles are on the bike? |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by Fahad on 05/26/16 at 12:40:13 11000 miles. It has a stock muffler and it rides smooth. The other day I rode on the highway for about half hour. When I got back the pipe was hot. Is that normal? 457E7364757962647F777A65160 wrote:
|
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by justin_o_guy2 on 05/26/16 at 12:46:14 GENTLY snug the header bolts on the head. If you feel like it's not tightening up, back one side off, clean, put a dab of antisieze on, and snug it up, same thing on the other side. The gasket looks like a miniature clothes dryer exhaust. It's reusable and can be pulled out, the head cleaned up, header cleaned, gasket carefully pulled a little longer. Mine was backfiring so much that the people on the ride were bothered, I was kinda embarrassed, but the fix was stop the leaks, but that didn't get it all. Made it reasonable. The cam swap and Supertrapp muffler made rejetting necessary. And it sounded Sooo good, snarling and growling through the downshift s. |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by Dave on 05/26/16 at 12:53:43 5B7C757C791D0 wrote:
Absolutely! The exhaust pipe on any motorcycle is hot. It will melt or burn almost anything that comes in contact with it.....rainsuits, saddlebags, boot soles, polyester leisure suits! |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by Armen on 05/26/16 at 13:26:57 Hey Fahad, It takes a while before engine damage happens. If it was mine I'd do the rejet thing. As the other folks said, an exhaust leak is possible. The gasket is cheap enough, just pull the pipe and put in a new one. When I hear of these symptoms (blue pipe, backfiring on trailing throttle) it usually means lean jetting on the low end. Pollution tests are done only up to legal speeds. At 55 mph, the throttle isn't open much, so you are on the pilot jet, the mixture screw, and the needle taper/position/needle jet. I don't usually have to do anything with the main jets. Enjoy your new ride :) -Armen |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by Dave on 05/26/16 at 13:38:07 Well there is not doubt that the Savage (and just about every other EPA compliant motorcycle) comes jetted lean from the factory. My Savage had a lean surge just off idle, and when attempting to ride away at low throttle settings the bike just didn't want to accelerate smoothly. It was fixed with a #50 pilot jet, #150 main and 2 washers in place of the white spacer on the needle. The Rescue bike had the same....and it wanted a #52.5 pilot, #150 main, and 3 washers on the needle. My Kawasaki Super Sherpa 250 dual sport was jetted so lean that you had to sit in the driveway for more than 5 minutes warming the bike up before you could put the bike in gear and ride off....it would just stall if you made an attempt to ride it before it was fully warmed up. The SuperSherpa forum had a cure they called the Jekyll mod.....new larger jets and an adjustment of the idle fuel screw. My Ninja 250 also had the lean fuel mixture issue, and the forum for those bikes had the recommended jets to use. The bike will generally run with the lean EPA jetting - but they run better with a bit richer mixture! Thank goodness we have forum member who have worked it out....and we can still buy jets to make the bike right! |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by justin_o_guy2 on 05/26/16 at 14:44:45 The engine and carb are the same as the first year. The jets have changed,down through the years, as the EPA has dictated more and more from the manufacture rs, Go back and see what they were equipped with back in the day.. |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by verslagen1 on 05/26/16 at 14:53:57 716E686F72754474447C6E62291B0 wrote:
bad advice JOG, the carbs were jetted completely different back then. get a jet kit from lancer which has a range of jets. go up a size progressively till you find the one that works best for you. all locals vary, due available gas, altitude and humidity. In the tech section there's a progressive guide. |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by justin_o_guy2 on 05/26/16 at 15:17:04 I was not giving advice. I was pointing out that the EPA has forced change. |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by springman on 05/26/16 at 16:04:47 I have the jet kit from Lancer and the stainless steel screws from Dave but as my bike seems to run quite well I have not yet changed the jets.Yes, there is some bluing on my pipe and I am running an HD muffler. I actually like the noise of the afterburn (not really a backfire) as it helps to warn cars I am nearby. By the way, I do not get to ride to work as often as I would like but when I do it is about 32 miles each way, about 25 miles on the highway and HOV cruising at about 70 mph. I have about 21,500 miles on the bike. Ride it. Enjoy it. 8-) |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by Kris01 on 05/26/16 at 17:41:05 You can really tell a lean condition if the engine likes to surge at a constant throttle position. It's almost as if the clutch is slipping. I upped the jet sizes in my carb just slightly and it runs sooo much better. A little goes a long way! She ran great before but runs excellent now! |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by Kruzader on 05/26/16 at 18:38:08 4B707D6A7B776C6A7179746B180 wrote:
Absolutely! The exhaust pipe on any motorcycle is hot. It will melt or burn almost anything that comes in contact with it.....rainsuits, saddlebags, boot soles, polyester leisure suits![/quote] My gf's foot. LOL rode it to do an oil change and asked her to stand it for me...didnt notice she had no shoes and what's the first thing she touches, the exhaust. OUCH lol....i think i slept on the couch that night. |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by RaleighGuy on 06/24/16 at 12:09:53 In the 7 days I've had my S40, I've ridden almost 300 miles and noticed almost every single time I slow down, there's a backfire. Loud, subtle or somewhere in between, but pretty much every single time I come to a stop. I just assumed it was normal for the Thumper to sputter a little bit. 8-) |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by justin_o_guy2 on 06/24/16 at 13:33:10 Mine slowly became just embarrassing. The header bolts were loose and getting looser. Gently snug them up, use a 1/4" ratchet, very gently on those wimpy things. Repairs in there are hard. Check out the clamp on the muffler, too. |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by Doc on 06/24/16 at 13:43:03 Hello from NC. Just jumping in here as Im new to both this forum and my 2007 Savage. My bike backfires on deceleration(and one little "woof" out the tailpipe when I shut it off!) Also a blue pipe. Would like to correct (backfiring)this to some degree as it drives my wife bonkers. The bike seems to run ok, although it seems to work very hard accelerating, as if the thing is trying to make power, but can't. Seems as if it could run with a bit more spirit like some of my past bikes. I read the discussions about shim kits, slide needles, blanking plugs, etc, but I really don't know what all that means. My real need is to find a great source to teach me some of the basics so I can take advantage of the knowledge this forum seems to have. |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by verslagen1 on 06/24/16 at 13:51:44 If you need to find a mentor... http://suzukisavage.com/cgi-bin/YaBB.pl?num=1444445797 Where are all the Hot Shots hang... http://suzukisavage.com/cgi-bin/YaBB.pl?num=1454499524 |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by Savageman on 06/24/16 at 14:07:20 Squack! Yes both of my Savage's had the popping issue and both required rejetting the carb. I used a 52.5 pilot , 150 main and 2 washers on the needle for both bikes. I bought 2 kits form Lancer. Make sure the exhaust is completely sealed up and it removed 95% of the popping. I'm using a Harley Dyna muffler also. Sounds good and accelerates smoothly. I'm at 200ft elevation here and not humid with fairly hot temp 90s. 8-) |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by Kris01 on 06/24/16 at 17:18:37 See signature. Works great for me. I'm at a few feet above sea level with lots of humidity and temp in the 90-100s. |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by sauvage on 06/29/16 at 08:34:32 Here's some good info on backfiring, scroll down to the 'Burn Baby Burn' sub heading. I've seen bits of this post all over the internets but I tracked down the original post. http://tinyurl.com/hgsasoo |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by sauvage on 06/29/16 at 08:54:34 Here's some good carb tutorial stuff http://www.iwt.com.au/mikunicarb.htm 676C606A6D606C716D030 wrote:
|
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by justin_o_guy2 on 06/29/16 at 13:41:20 Look in the Technical part of the forum. Serowbot, I think, posted a good, Readers Digest level How to understand what the bike is telling me about the carburetor explanation. It helped me.. can't remember it, but it made sense.. And I am not a carb guy.. |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by batman on 06/29/16 at 14:12:50 If you want to enjoy riding more ,you need to read more ,the tech section ,FUEL&EXHAUST, knowledge is power!! |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by DavidOfMA on 06/29/16 at 18:54:42 One other method not yet mentioned: modifying the Transient Enrichment Valve (TEV), a small vacuum-operated valve on the right side of the carb. I could not get the backfires on my 2007 S40 to stop by any of the standard methods: eliminating exhaust leaks (there weren't any), adjusting the idle mix screw, changing jets. What finally worked for me was taking a small amount off the spring that is part of the TEV. If the standard methods don't work for you, I suggest taking a very small amount off the spring (such as 1/4 turn), then test for backfires for a couple of days. If you still get backfiring, take a little more off and test again. If you weaken the spring too much, the valve will open too easily and you'll get a surge at idle, but if you weaken it just a little, the time it stays open on decel will increase but idle will be unaffected. In my case, removing 1/2 round of the spring weakened the spring just enough to almost completely eliminate backfires. Just driving around town, it never backfires. On a recent 300+ mile trip, on a variety of roads and speeds, I had a total of 3 backfires. Before this mod, I'd have more backfires than that on my 6-mile trip to work. My two cents. David |
|
Title: Re: S40 Backfiring- Do I really need to fix it? Post by KennyG on 06/29/16 at 20:21:00 David, I concur with your conclusion. Kenny G |
|
SuzukiSavage.com » Powered by YaBB 2.2! YaBB © 2000-2007. All Rights Reserved. |