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Message started by jmerry on 09/27/06 at 14:04:12

Title: Belt Pulley
Post by jmerry on 09/27/06 at 14:04:12

Does anyone know if there is a larger belt pulley available for the LS650? This would "gear up" the bike slightly and allow for higher speeds with lower RPM's. I've seen the sprocket changed out on chain driven dirt bikes to acheive this. It would seem to be an easy mod if anyone had fabricated one and marketed it.

Thanks!!

Title: Re: Belt Pulley
Post by Dynobob on 09/27/06 at 14:46:45

jmerry wrote:

You want a smaller rear sprocket or a larger front sprocket. No I don't know of any being made. It would be a very good mod to have manufactured. Perhaps something from a different model Suzuki would fit ? ? ?

Title: Re: Belt Pulley
Post by jmerry on 09/27/06 at 15:49:55

Either way would work, although the front drive pulley would be much easier. The only limitation would be room in the crank case housing, but there seems to be ample. It just seems to be a simple mechanical solution to a bike with LOTS of low end torque, but limitations on the top end due to high RPM's. Does anyone know if Dynobobs solution would work? Has anyone tried another bike's drive pulley? I'm dying to know if this would work or has been tried..

Thanks!!

Title: Re: Belt Pulley
Post by thumperclone on 09/27/06 at 17:56:05

1 tooth front = 3 teeth rear
if you ever find any get me one too!!!

Title: Re: Belt Pulley
Post by SavageDude on 09/27/06 at 22:18:59

Even if you manage to find the pulley mod, you will need a small diameter belt :o Another mod ::) just to lower RPM.

Title: Re: Belt Pulley
Post by Odar on 09/27/06 at 22:52:16

For a bigger front pulley, anybody did the calculation, howe mutch bigger in dia. and howe many teth for 8-10 % change in RPM?
For a little bigger front pulley you can always move the rear tire forward in the svingarm.
Odar

Title: Re: Belt Pulley
Post by klx650sm2002 on 09/28/06 at 03:39:27

On My KLX I went from a 43 to a 46 which dropped top speed from 107 to 100, much better acceleration.

Seems you guys want to go the other way.

How many teeth on your pulleys, front and rear ?

Clive W :D

Title: Re: Belt Pulley
Post by jmerry on 09/28/06 at 05:42:52

That's right. A larger front drive pulley, or a smaller rear. The difference needed to the belt could be made up by moving the wheel forward slightly in the swing arm.

Not sure about the number of teeth on either pulley. I wonder if an HD pulley would work? I don't think there's another Suzuki bike that uses a belt drive.

Title: Re: Belt Pulley
Post by bentwheel on 09/28/06 at 07:49:11

jmerry wrote:

Either way would work, although the front drive pulley would be much easier. The only limitation would be room in the crank case housing, but there seems to be ample.

I doubt you could fit a larger front pulley. It is so tight in there, you have to remove the pulley just to remove the belt . Plus don't forget the belt will swell due to centrifugal force.

Title: Re: Belt Pulley
Post by lancer on 09/28/06 at 07:57:41

The rear pulley on a Savage has 68 teeth, 23 up front. HD's have a 65 tooth pulley but the bolt pattern is different. It should not be difficult to take one to a machine shop and have new holes drilled to match the Savage, and it would also probably need to have a bearing insert pressed in to match the axle size on the Savage. Easy stuff for a machine shop.

Title: Re: Belt Pulley
Post by jmerry on 09/28/06 at 08:08:34

Mmm.. Then that would leave a smaller rear pulley. Any of those around?

Title: Re: Belt Pulley
Post by Enfield_fan on 09/28/06 at 08:58:13

I still think the answer is a smaller primary drive sprocket on the right side of the transmission, with a correspondingly shorter primary drive chain.

Title: Re: Belt Pulley
Post by vroom1776 on 09/28/06 at 09:04:17

Most HD belts are not as wide as ours, though.

Title: Re: Belt Pulley
Post by serowbot on 09/28/06 at 09:58:26

I just went to a 90 profile tire to get a little gearing. Tight fit on a stocker, but I have 12.5" shocks.

Title: Re: Belt Pulley
Post by klx650sm2002 on 09/28/06 at 10:11:14

90 profile gives 4.6% more speed for the same engine revs.

Going from a 68 to a 65 (if possible) tooth rear pulley also gives 4.6% more speed for the same revs.

The two together gives 9.4%.

Clive W :D

Title: Re: Belt Pulley
Post by Savage_Rob on 09/28/06 at 14:03:19

Yeah, I always forget about that. So when indicated speed on the freeway each day says 70, it's a bit over 73 in reality. Of course, as the rubber wears away on the tire, that changes... but that happens on any tire.

Title: Re: Belt Pulley
Post by serowbot on 09/28/06 at 16:57:55

Motorcycle speedo's are notorious for overestimating the true speed.
I have been kind'a assuming my speed to be closer to accurate with the 90 profile tire.

Has anyone here ever tested the savage for MPH accuracy?

Title: Re: Belt Pulley
Post by babbalou on 09/28/06 at 17:48:06

serowbot wrote:

Around here sometimes the cops put out a big electronic sign that reads your speed & indicates it in large letters. Last time I rode past one I checked & my speedometer was spot on at 40 mph with my 140/90 tire. Not sure if it's that close at other speeds but I'll be checking it when I can.

Title: Re: Belt Pulley
Post by SavageDude on 09/28/06 at 17:49:16

Well according to 1 of those electronic sign that display your current speed on the side of the road with radar gun in it shows that our speedo speed is accurate. But then again how accurate is that radar gun calibrated is another story.

Title: Re: Belt Pulley
Post by jmerry on 09/29/06 at 06:49:03

Who is a good vendor for these jets? I've seen a link here somewhere...

Title: Re: Belt Pulley
Post by Enfield_fan on 09/29/06 at 09:46:31

Elton John says "Talk to Benny."

Title: Re: Belt Pulley
Post by Rogue_Cheddar on 09/29/06 at 09:49:19

serowbot wrote:

I'm my way to work there is a school zone where the local Gendarmes setup one of those Radar signs that tell you how fast your going. When it finally settles down on my bike it says 20 mph which is right on what my speedo is telling me. My bike is stock '95.

Title: Re: Belt Pulley
Post by georgekathe on 10/03/06 at 00:33:18

I also matched the Savage against a couple of those "Your Speed Is..." signs & found unlike most bikes it to be pretty accurate (with a "standard/stock" tire on), unlike my other bike which like all BMWs is around 10 mph "flattering" @ about 75 (ie the "speedo," to use an old English nickname, reads 85 mph).

Sure wish it was easier to change around the gearing than it seems to be - I recall messing around to my hearts content with front & back sprockets on a Honda 650 single enduro I owned a few years ago.

still, I think I just want to tinker - I like acceleration & wouldn't want to lose it & think the top speed on the Savage, considering its weight, is good enough for me.

:)

Title: Re: Belt Pulley
Post by lancer on 10/03/06 at 07:11:27

When I put the Veypor on my bike, before removing the stock speedo, I checked it and found the stock speedo to be within +/- 1 mph ... this was with the new 140/90 tire on the rear.

Title: Re: Belt Pulley
Post by vroom1776 on 10/03/06 at 08:00:09

Hey Lancer,

Do you know what parts (p/ns) are needed for a chain drive conversion? It's been bandided around that sprockets from a DR 650 will fit, but I've not heard anything conclusive.

V

Title: Re: Belt Pulley
Post by Salad_Shaker on 10/03/06 at 08:27:08

A recent-ish survey of speedo accuracy by Bike magazine in the UK found that the most accurate are on the current crop of Triumphs, at just 2% out. Suzy's are better than Hondas and the worst, surprisingly perhaps, are BMWs, with, as someone else has noticed up to 10% over-reading. Saying you were misled by your own speedo is not a valid defence against a speeding ticket!

Back on belts and gearing, BMW have a mid-sized belt driven model, the bug-eyed 650CS Scarver. I tried to track down belt spec and pulley sizes but have so far drawn a blank. Any ideas?

Title: Re: Belt Pulley
Post by barry68v10 on 10/03/06 at 14:38:09

I have to completely agree that the primary drive sprockets and chain are the way to attack this problem due to the shear abundance, selection, and cheap price of chains and sprockets. Anyone know what kind/size these are? Are they double chains?

Title: Re: Belt Pulley
Post by Fido_the_Cat on 10/03/06 at 19:22:37

Chain and sprockets would give you a more smoother (dampen vibration) ride. Now think about this! Put on a chain drive that transfers the drive to a roller that rides on the tire. Saw it on a custom builder bike, and discussed it on another forum although unless your friendly with your neighborhood fabricator, chances are this will be an expensive mod.

Title: Re: Belt Pulley
Post by lancer on 10/03/06 at 20:48:33

I have seen the parts on one of the German websites before, but I would have to research that to find it again. I do not have time tonight but perhaps I can get the info in the moring.
If I forget to do this please remind me later tomorrow.

vroom1776 wrote:

Hey Lancer,

Do you know what parts (p/ns) are needed for a chain drive conversion? It's been bandided around that sprockets from a DR 650 will fit, but I've not heard anything conclusive.

V

Title: Re: Belt Pulley
Post by barry68v10 on 10/04/06 at 02:47:21

I need to clarify. The final drive is a belt. No mnx and actually better vibration dampening than a chain. However, on the right side, inside the case (haven't been in there yet) should be a chain and sprockets that transmit the power to the belt pulley on the left side. That chain is sealed and lubricated and should last a LONG time (50,000 miles plus.) However many of these I've seen are double chain, or even triple chain and sprokets which are way more expensive and less available than singles, but also way more durable.

If you've got 12.5" shocks, on the other hand, a smaller rear pulley may solve some belt guard clearance issues. Bad thing here is belts are not that common and finding the right length (shorter) belt might be tough even if you could find a pulley that would fit.

If you did jetison the belt drive for a chain drive on a streetbike I'd go with an automatic chain oiler...

Title: Re: Belt Pulley
Post by Odar on 10/04/06 at 10:19:04

Here is a link to a german company that make a chain conversion.
I dont speak german but you can always make a translation on the net.
The price is 199 Euro
Scroll down on the page and you see pictures
Link: http://www.savageshop.de/

Odar in Sweden
http://wb524292.bahnhofbredband.se/nytt6.jpg

Title: Re: Belt Pulley
Post by Odar on 10/04/06 at 10:27:30

Here is a translation from the german company, sorry to say its not perfect but I think you will understand most of it.

For a long time we had announced it and it is ready final! Hereby we introduce our Kettenversatzkit to you for the Suzuki LS 650 Savage.

Some will wonder: Kettenversatzkit? However who itself already once a new tooth-belt must buy, becomes we understand something with our Kettenversatzkit intends. Whoever still toys with the idea then, a wider behind-wheel in the Suzuki LS 650 Savage lasts upper-cool, a light now rises that! With our Kettenversatzkit, we offer you a possibility, about 2 problems with, to solve once.

1. opposite the Neupreis for one original tooth-belt is favorable unbeatable our Kettenversatzkit chain-wheel, chain-pinions, O-Ring-Kette and distance-material for only 199,00 €S incl..
2. through the mounting of the Kettenversatzkits becomes place sufficiently created a 4,50x15 inch of rim about the mounting with a 170er ring, that a proud width of 180 mm, to enable, reaches.

Is also available the 4,50x15 inches of rim incl. matching spoke-sentence with us. More information to the Felgekit here!

For the ones, that wish no wider behind-wheel, and skeptically the secondarily-chain with the original tooth-belts compares, is said that the secondarily-chain is laid out with its 530er division for motorcycles until 1200 ccms. Consequently the question of the durability of the secondarily-chain would like to be answered.

No particular tools are required to the montage of the Kettenversatzkits. The included mounting-instruction, that each of that has already changed a motorcycle a chain-sentence at any once, is so described our Kettenversatzkit without problems can install.

Technical details:

- Chain-pinions 17 teeth
- Chain-wheel 50 teeth
- Secondarily-chain 530HTP O-Rings, reinforces
- Translation-relationship 1 to 2,941 (original 2,956)
- Distance-material from noble-steel
- Mounting of tires until 180 mm width possibly
- It is necessarily swing no Verbreiterung of that!
- At that swinging must be removed only the mounting of the original Beltschutz!
- The original Zahnriemenabdeckung can not be used!

Delivery capacity:

- Chain-pinions MFC-Sonderanfertigung
- Chain-wheel MFC-Sonderanfertigung
- IRIS Sekundärkette 530HTP, closed
- IRIS Nietkettenschloß
- Distance-disk type AT 2 pieces
- Distance-disk type B 3 pieces
- Cylinder-screw with Innensechskant M6 xes 50 mm DIN 912 1 pieces
- Cylinder-screw with Innensechskant M6 xes 60 mm DIN 912 2 pieces
- Mounting-instruction

Price: 199,00 €S incl. MwSt >>> buys

Pictures of the delivery capacity and from the built-in condition of the Kettenversatzkits:

Odar
http://wb524292.bahnhofbredband.se/nytt4.jpg

Title: Re: Belt Pulley
Post by Odar on 10/04/06 at 10:30:50

And here is the translation about thre rim.

Felgenkit 4,50x15 for Suzuki LS 650 Savage
The Felgekit comprises a 4,50x15 inch of rim verchromt and a matching spoke-sentence from noble-steel. The rim is tested and has a part-certificate after § 19/3 StVZOs. At the time, the Suzuki is not yet LS 650 Savage in the certificate unfortunately however with presented. The TÜV-Prüfung directly for the LS 650 Savage shall 2003/2004 in the winter approximately however after is gotten.

That swing must widen as well as altered, but with some is revised (fold-edge überschleifen). the shockers remains at the original position. The original mudguard can be used no longer and of course also not the original tooth-belt. Our Kettenversatzkit must be used as drive.

Bestell-Nr.: MF 41-410
Price: 634,00 EURO incl. MwSt

Following 170er tires can be obstructed on the rim:

- Bridge-tones 170/80-15 77H G544
- Dunlop 170/80-15 M/CS 77H TTS K555
- Metzeler 170/80B15 77H TLS ME880

The tire has a width of approximately 180 on the 4,50x15 inches of rim mm.

Odar
http://wb524292.bahnhofbredband.se/nytt2.jpg

Title: Re: Belt Pulley
Post by Dynobob on 10/04/06 at 21:24:51

That's interesting Odar and not a bad price considering you get an O-ring chain with the kit. Cool. Shipping might be prohibitive though.

Title: Re: Belt Pulley
Post by Dynobob on 10/04/06 at 21:35:42

Gear ratios:

Stock belt drive: 2.956

German chain drive conversion: 2.941

Hmm, very little change but definately a lower ratio.

Title: Re: Belt Pulley
Post by Rockin_John on 10/05/06 at 00:42:04

In my experience, the REAL problem with the Savage's gearing isn't in the Primary/Secondary drive, or final (belt) drive, but the transmission gearing itself. While that makes it a much harder problem to solve, it is the ultimate answer IMHO.

Note though, that my 4-speed 1987 is the only Savage I've ridden, so I don't know exactly what the ratios are in the late model 5-speed versions. I'd like to know myself, does the 5-speed have a lower first gear, like I wish my 4-speed has? I'm fairly sure that 5th is the same as 4th on the 4-speed. Is it possible that they just added one more gear to make an even more "close ratio" transmission? (Which the torque strong thumper doesn't need anyway. While I wouldn't WANT it this way, the Savage could get by with a 3-speed tranny... Granny, second, and overdrive! IMO, 4-speeds was plenty for this powerplant, they just needed wider ratios!

Answering the suggestion that the "primary chain drive" might be altered is a dead end, as the transmission is driven directly by helical (slanted) cut gears. Which DOES however, open the possibility of having those two gears cut at a different ratio, which would alter the drive ratio throuhout the remaining driveline.

Now, having said that; things I have learned through my research of the whole belt pully / chain drive issues that may close some dead ends:

Harley belts have different shaped teeth, and width, so they won't work on the Savage, unless you changed both gears and the belt + conversion = cost prohibitive.

Suzuki only offers one length of belt, so even if you had some custom pullys machined, unless you kept the change/s within the tolerances of stock belt's adjustment, you would be out of luck.

As for chain conversions: that would open up a host of gearing possibilities, and also allow for wider rubber on the rear (up to a point, then you run into recommended rim width problems) Hense, the offered wide rim on the German site which allows for some serious wide rubber. (And acording to my measurements with digital calipers, belt to tire clearance is by far the most limiting factor in increasing tire width.)

So... In summation, IMHO the ultimate solution would be to split the cases, and have custom shafts/gears machined for the transmission (which uses all simple straight cut gears. Yet still very costly and labor intensive.

The alternative of changing the primary drive gearing is attractive because it doesn't requre splitting the cases and reassembling that whole mess, and allows keeping the nice clean belt drive (albiet at the cost of not allowing a super wide rear tire for those so inclined.) While it has the huge disadvantage of having to engineer and machine helical cut gears to an exacting spec. ($$$)

It seems that the chain drive, while far from ideal, is the most cost effective way to raise/lower the overall gearing on the Savage. And as someone mentioned... $199 Euro isn't that bad, considering the cost of the included o-ring chain. Shipping could be a bit high. Maybe as much as $75 -$100 US to get the kit here in a reasonable amount of time (a week or two).

So what it boils down to, after all my investigation over past weeks, including things I learned in this thread, is: I don't think I'll change ANYTHING in my driveline, and just live with it like it is!

I ~might~ change tire sizes, but I'd like to investigate that in another thread.

Title: Re: Belt Pulley
Post by Odar on 10/05/06 at 02:54:12

RPM-Km / hour
5 Gears Savage
Picture Link (http://smg.photobucket.com/albums/v124/Odar1/Odars%20Savage/?action=view¤t=KmRPM.jpg&refPage=&imgAnch=imgAnch1)

Odar

Title: Re: Belt Pulley
Post by Odar on 10/05/06 at 02:58:57

Sorry, didnt change the values at the bottom of the picture 1 = 1000 RPM then its 500 RPM higher betwen the dots......12 = 6500 RPM

Odar

Title: Re: Belt Pulley
Post by barry68v10 on 10/05/06 at 03:03:50

Odar, the left (y-axis) scale says Km/Hr, but I think it's really MPH. The 5-speed Savage does 4000 RPMs at 60 in 5th gear. (with stock tire)

Title: Re: Belt Pulley
Post by barry68v10 on 10/05/06 at 03:05:08

OK, I see your post now, that makes more sense... ;)

Title: Re: Belt Pulley
Post by Odar on 10/05/06 at 06:01:22

Here it is corrected RPM Km/h (http://smg.photobucket.com/albums/v124/Odar1/Odars%20Savage/?action=view¤t=KmRPMcorr.jpg&refPage=&imgAnch=imgAnch1)

Odar

Title: Re: Belt Pulley
Post by Salad_Shaker on 10/05/06 at 11:29:29

Over on Bert's pages RIP ages back there was a reference to a company in New Zealand that made a conversion kit for chain drive, but I've long since lost the reference. I believe the parts from the Savage 400 are a straight fit, but as it was never officially imported here (to Europe that is) sourcing the bits could be tricky.

The downer on going over to chain is maintenance and wear in addition to the loss of smootness already referred to by others.

Title: Re: Belt Pulley
Post by barry68v10 on 10/09/06 at 13:15:57

There may be a breakthru here: I'm waiting for a response from scootworks.com out of NC. They have several belt conversion kits for lots of Jap bikes including the marauder. I'm betting that kit would work on the savage with minimal mods and it would give you a 2.2 ratio. Very comfy for highway cruising! Only thing is it's almost $500. More than twice as much as the german chain conversion.

Title: Re: Belt Pulley
Post by Rockin_John on 10/09/06 at 21:37:29

barry68v10 wrote:

Personally, I'd be more inclined to pay twice the price for a good belt drive system; than to go to a chain. The Savage is my first belt drive bike, and so far I've loved it. No torque steering and jacking like my previous (albiet trouble free) shaft drives; and also no mess and noise like a chain. I'm quickly becoming convinced that a belt is the only way to go on street cycles.

Title: Re: Belt Pulley
Post by barry68v10 on 10/10/06 at 00:06:35

I'm with you! This is my first belt drive bike too. I recently put a new chain on my son's dirt bike and after only a couple months it's already wearing unevenly, it's got a distinct tight spot and loose spot. We only forgot to clean it up once and I'm convinced the next ride (less than 2 hours) is what killed it. I know a belt wouldn't do well on a dirtbike, but it seems a chain is the worst in both worlds. Not bullet proof/mnx free as a shaft off road and not as quiet/efficient/mnx free as a belt on road. I wonder why more offroad bikes don't have shaft drive and why more street bikes don't have belts? The little 50cc yamaha dirtbike is a shaft drive, and the buell blast and the savage are the only belt drive bikes I know of under 1000cc's. I guess that's why scootworks has the conversion kits.

Title: Re: Belt Pulley
Post by Savage_Rob on 10/10/06 at 06:54:14

This is my 1st with a belt and I love it. Back in the mid 80's, a friend had a Honda (350 Four, I think) that had a belt drive and it was my first experience with one. Seemed good then and I'm sold now. I may try to pick up a spare on eBay at some point too. Another thought: I would definitely expect less damage from throwing a belt than a chain.

Title: Re: Belt Pulley
Post by jmerry on 10/10/06 at 06:57:16

I second that. Whenever you guys find that supplier, let us know!

Title: Re: Belt Pulley
Post by barry68v10 on 10/13/06 at 14:03:51

UPDATE: It is with a heavy heart that I announce Scootworks has no belt/pulleys for re-gearing or replacing the Savage stockers.

If I can find a shorter belt from some supplier, I'll look into fabrication costs for a new rear pulley. Again, like anything else, if we got a BUNCH of people committed to buying one it could bring the per-unit cost way down. Anyone know how to find a shorter belt with the same width and tooth pattern?

Title: Re: Belt Pulley
Post by barb36jack31 on 10/16/06 at 17:54:56

I guess my question is WHY? My 05 S40 with all the usual mods pulls like a tractor from idle to red-line. It will nearly haul the ton sitting bolt upright and if I got under the paint, it would clear 100 mph no sweat. Why fiddle with a system that works this well?

Jack H.

Title: Re: Belt Pulley
Post by barry68v10 on 10/16/06 at 18:50:50

Great question Jack! The real answer is...it depends!
It depends on what you want. For me, I've had some pretty fast bikes in my day, bikes that would do 0-60 in 3 sec or less. I'm just not interested in that kind of thing anymore. I want a bike that lopes along at 70 mph and doesn't sound like I'm trying to break land-speed records doing it. A single-cylinder bike is the proverbial loping engine with the torque to back it up. I'd like 2500-3000 rpms (less if I thought it were reasonable) at cruising speed which would turn the lowly Savage into a touring machine. Big bike guys won't readily admit it, but the real thing that makes a comfy touring bike is a comfy rpm on the highway that doesn't produce a bunch of vibrations and sound.

If, on the other-hand you want to use the high torque/low rpm thumper for quick acceleration don't change a single thing! You've already found the machine for you. :)

Title: Re: Belt Pulley
Post by Savage_Rob on 10/17/06 at 11:31:36

barb36jack31 wrote:

Well, it sounds like you're pretty satisfied. If that's true, there's no reason to fix what ain't broke. For me, it's just a tinkering thing.

Title: Re: Belt Pulley
Post by jmerry on 10/17/06 at 14:20:08

barry68v10 wrote:

I couldn't have said it better.. It's all in what you want. I would like for my S40 to run 70-75 without turning 4500 rpm.

Title: Re: Belt Pulley
Post by vroom1776 on 10/17/06 at 15:02:29

jmerry wrote:

I couldn't have said it better.. It's all in what you want. I would like for my S40 to run 70-75 without turning 4500 rpm.

Tell that to my shaft drive V* !

Title: Re: Belt Pulley
Post by Stimpy on 10/23/06 at 12:41:19

BTW

Something that just MIGHT fit the savage as a smaller rear "sprocket" (after some drilling and welding a la McGyver that is) is one of those wheels from those old style pulley ventilator systems.

You know, a bunch of celling fans all interconnected by leather belts & pulleys but all ran by one electric motor mounted elsewhere on the wall. A real hoot to watch´em spinning too.

http://www.architecturalfans.com/
See under "Motor & lineshaft"

Or maybe some kind of automotive fan wheel, the problem, again, are the teeth.

I mention this because in my case 1st gear is USELESS, period. And it would be great if 2nd and 3rd could be a little longer, I mean, all that torque has a lot of potential. But I also like better 4th rather that 5th gear for high speeds.

As someone said earlier "this thing pulls like a tractor" so a 10-15% smaller rear "sprocket" would surely make an interesting expetiment.

Then again the problem at high speeds would be wind resistance. It´s all in the numbers.