Jump to content

Chain slack/Axle adjustment


Tpoppa

Recommended Posts

...so most of my riding has been on belt drive Buells over the last 7 seasons.

Buells have a fixed rear axle with no adjustment. A 3rd pulley in the middle insures the belt has the proper tension. It's a really easy setup to work with and you always know your axle in perfect alignment.

050808middle2.jpg

Why don't chain drive systems have this? Why not have a fixed axle and a 3rd sprocket to adjust tension/slack? It could be spring mounted to ensure than the chain wasn't too tight.

There must be a reason...and yea, I just got done messing with chain on the SV.

Link to comment
Share on other sites

there's some kind of mechanical advantage with chains, or the Buell race bikes would run belts.

There's actually an advantage with the belt. Belt and pulleys are something like 2 or 3 pounds lighter than chains and sprockets. You can't change the gearing with belts, that's why the race bikes use chains.

Link to comment
Share on other sites

why couldn't they just change the pulley carrier sizes and get the same effect of changing sprockets?

Per your explanation of the pulleys, the slack adjuster would just need to take up a bit more with a smaller rear sprocket, and a bit less with a larger one.

Link to comment
Share on other sites

Just taking a stab...

-reliability issues with a pulley on the chain drive (multiple forces on the chain = more wear)

-performance concerns with belt vs chain. My assumption, belt is more elastic under high torque situations. Constant heating cycles on the belt degrades perf more than a metal chain

The belts probably werent designed to endure the environment found in racing...maybe.

just guesses from me...

Link to comment
Share on other sites

not that it's 100% relevant to this thread, but I am strongly in favor of always counting the number of rotations on your axle adjusters rather than going by the little marker lines.

If you don't have string and some jack-stands to do a real alignment check, counting the turns has seemed to be the next best thing for me.

Link to comment
Share on other sites

not that it's 100% relevant to this thread, but I am strongly in favor of always counting the number of rotations on your axle adjusters rather than going by the little marker lines.

If you don't have string and some jack-stands to do a real alignment check, counting the turns has seemed to be the next best thing for me.

String........ Please elaborate. I've done it w the marks or bolt turns. Never really felt 100% though, and for an anal retentive guy that's not good

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

why couldn't they just change the pulley carrier sizes and get the same effect of changing sprockets?

You would need a different length belt for every gearing combination. Belt tension has to be precise or you will shear off teeth.

Link to comment
Share on other sites

String........ Please elaborate. I've done it w the marks or bolt turns. Never really felt 100% though, and for an anal retentive guy that's not good

Sent from my iPhone using Tapatalk

That was pretty much the reason for my original question. A fixed axle makes life much easier.

Link to comment
Share on other sites

Maybe, I should be dead for doing it this way, but when I changed my rear tire, I didn't mess with my adjusters, I knocked the axle out rolled the wheel forward to get the chain off then reversed it. Adjusters never moved so I could only assume that its still aligned.

Link to comment
Share on other sites

I only align a chain with eyeball. I look at the rear of the rear sprocket while turning the wheel in an upright vertical position. I'll adjust the rear axle alignment till the sprocket is running straight in the middle of the chain. Check chain tension. Repeat. Tighten axle. Check chain tension. Repeat. Old school. If it comes out weird, somethings broken.

This will not work well with a bent swing arm. Not even a little bit bent.

Link to comment
Share on other sites

Maybe, I should be dead for doing it this way, but when I changed my rear tire, I didn't mess with my adjusters, I knocked the axle out rolled the wheel forward to get the chain off then reversed it. Adjusters never moved so I could only assume that its still aligned.

I see no problem with this, as long as the chain is adjusted properly when you started. This is exactly how I did my rear tire Friday, and after riding it like a 2.00$ whore Saturday, all is ok still.

This is a reminder that I need to check, and maybe adjust the axle alignment on the 250. A bit off-topic here, but I'm wondering if it is off some, and what is causing my bars to be turned to one direction slightly when riding down the road. The bike had been down a couple times when I got it, with no fairings, etc. so it's possible that something is bent. It still handles pretty well anyway.

Link to comment
Share on other sites

A bit off-topic here, but I'm wondering if it is off some, and what is causing my bars to be turned to one direction slightly when riding down the road.

Loosen all the torqued front end, and see if it will eyeball twist straight. Then re torque in sequence, per the shop manual. Just compressing the front forks when everything is loosened, will do a lot for straightening. Bent handle bars are the most common "off center" steering cause, but the front forks can twist a bit off over time.

Link to comment
Share on other sites

Loosen all the torqued front end, and see if it will eyeball twist straight. Then re torque in sequence, per the shop manual. Just compressing the front forks when everything is loosened, will do a lot for straightening. Bent handle bars are the most common "off center" steering cause, but the front forks can twist a bit off over time.

I've tried that, maybe I will again, paying more attention. It's definitely something I can see at the triples, and the bars are more like a clip on, but they bolt to the triples, above the top of the tubes.

Link to comment
Share on other sites

I've tried that, maybe I will again, paying more attention. It's definitely something I can see at the triples, and the bars are more like a clip on, but they bolt to the triples, above the top of the tubes.

I'd take some measurements, point to point, comparing both sides. Find where it is. Sounds like it's up top, around the triples or bars.

And yes, you need some giant calipers to measure with.

Link to comment
Share on other sites

I'd take some measurements, point to point, comparing both sides. Find where it is. Sounds like it's up top, around the triples or bars.

I think the triples might be the culprit. I should just ebay me a set. I THINK they go cheap enough on there. :dunno: maybe I should look into it.

Link to comment
Share on other sites

String........ Please elaborate. I've done it w the marks or bolt turns. Never really felt 100% though, and for an anal retentive guy that's not good

String technique I've used to double check alignment is take 3 or 4 foot length string and hold to centerline of the swingarm pivot and then stretch taught to centerline of the rear axle - then either mark the string or dont let go to check other side same way. Basically a cheap, easy measuring tool to ensure the axle is close to perfect parallel with the swingarm pivot as possible

Link to comment
Share on other sites

String technique I've used to double check alignment is take 3 or 4 foot length string and hold to centerline of the swingarm pivot and then stretch taught to centerline of the rear axle - then either mark the string or dont let go to check other side same way. Basically a cheap, easy measuring tool to ensure the axle is close to perfect parallel with the swingarm pivot as possible

Something like this tool works better, since there is no guarantee that either the axle or the swing arm pivot points are equal distance left and right of the motorcycle's center line. But the difference using a string would be very little.

WheelAlignmentTool_sm.jpg

http://www.muzzys.com/WheelAlignment/WheelAlignmentTool_sm.jpg

Also can use string and jack stands to line up along the rear tire, going forward past the front tire, and see where the front tire is actually located. A lot of careful adjusting to get the strings straight, and then some careful measuring to see where the front tire is. Note: A few bikes, like some BMW, have an offset front tire.

This is good for bikes that have really out of alignment front vs rear tires. Hopefully the sprockets and chain go along with aligning tires instead of chain/sprocket/axle. In general, it's probably better to just align chain and sprocket, or square the rear axle.

Link to comment
Share on other sites

Sounds like Beemer, offsetting the trail - why though? Other than just to be different, that is. It cant really improve handling or Honda would be doing it;)

Oh, and I would ALWAYS align the chain to the sprockets - thats where it would need alignment most.

I used the string just for another reference point. Along with using the axle block markings, eyeballing line-of-sight down the chain with slow rear tire spin, and checking sprockets for sideplate contact - yeah, I'm one of those anal fella's too:D

Edited by Hellmutt
Link to comment
Share on other sites

i'm going to take a wild guess with excessive wear. I really don't know if that has anything to do with it but if I remember how my friends Buell works, if you were to do the same thing with a chain, both sides of the chain would wear as opposed to just one like the standard sprocket/chain setup

Again this is just a guess and by no means educated

  • Upvote 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...