Jump to content
Sign in to follow this  

G#$%D$%& chain roller (DR650)

Recommended Posts

I had a casualty....didn't even notice it was gone until adjusting rear preload. Mine came out but vibrated out......still has threads!

Share this post


Link to post
Share on other sites

My upper roller has some grooves, but not deep ones. Jesse recently offered this opinion on the Yahoo DR650 list :prof: :

"I do not recommend removing both rollers they are not the cause of the upper roller threaded boss breaking either the chain is adjusted to tight or the weld around the threaded boss is not complete. If you throw a chain you will have more serious damage then a broken roller boss."

So for now, I'm leaving it on, but keeping a close eye on it for further wear and checking chain tension more often. If starts to look worn, I'll replace with Jesse's bearing rollers. Of course, if the weld is weak (pretty hard to tell by looking), I could end up with a hole to repair :cry: No perfect solution I guess. :confused:

Share this post


Link to post
Share on other sites
My upper roller has some grooves, but not deep ones. Jesse recently offered this opinion on the Yahoo DR650 list :prof: :

"I do not recommend removing both rollers they are not the cause of the upper roller threaded boss breaking either the chain is adjusted to tight or the weld around the threaded boss is not complete. If you throw a chain you will have more serious damage then a broken roller boss."

So for now, I'm leaving it on, but keeping a close eye on it for further wear and checking chain tension more often. If starts to look worn, I'll replace with Jesse's bearing rollers. Of course, if the weld is weak (pretty hard to tell by looking), I could end up with a hole to repair :cry: No perfect solution I guess. :confused:

Both rollers? My lower roller, a Jesse bearinged unit, is still intact and will remain that way. :thumbsup:

Share this post


Link to post
Share on other sites
Both rollers? My lower roller, a Jesse bearinged unit, is still intact and will remain that way. :thumbsup:

The grooves that are found on the roller; please note how uniform they are, same depth all the way around, as if the roller were formed with them from the tool that created them. These grooves are meant to be there and do not indicate wear. Look at a brand new bike they have grooves too. The grooves serve a purpose, as does this chain guide. I'm not going to second guess the engineers at Suz. as to the need for this. There is most likely a better after market part, but to remove it without any regard to it's function... ahh I don't think I want to travel on that slippery slope.

If the weld is weak then that is something different. Suz should have published a notice on it. My weld looks fine unless there are cracks under the paint. That condition could be true anywhere on the frame.

I think the condition for a failure is a fully bottomed out shock. Unless you are jumping the bike with the stock spring, I don't there is any reason for concern.

Share this post


Link to post
Share on other sites
The grooves that are found on the roller; please note how uniform they are, same depth all the way around, as if the roller were formed with them from the tool that created them. These grooves are meant to be there and do not indicate wear. Look at a brand new bike they have grooves too. The grooves serve a purpose, as does this chain guide. I'm not going to second guess the engineers at Suz. as to the need for this. There is most likely a better after market part, but to remove it without any regard to it's function... ahh I don't think I want to travel on that slippery slope.

If the weld is weak then that is something different. Suz should have published a notice on it. My weld looks fine unless there are cracks under the paint. That condition could be true anywhere on the frame.

I think the condition for a failure is a fully bottomed out shock. Unless you are jumping the bike with the stock spring, I don't there is any reason for concern.

With 12 full posts under your belt I can see how "I don't (think) there is any reason for concern" is logical to you. Try the search function, once you learn how to use it, and you will see there is a concern. Since you say "I'm not going to second guess the engineers at Suz." Why are you saying "I think the condition for a failure is a fully bottomed out shock" Isn't that statement saying the Suzuki engineers did not do their job since every engineer knows someone will allways take it to the limit? :thumbsup:

Share this post


Link to post
Share on other sites

Would this chain roller breakage be something that's more likely to happen on DR used primarily for offroad riding as opposed to street riding?

Share this post


Link to post
Share on other sites

There were two things mentions in the recent set of posts that I'd like to discuss.

First, there was mention of that roller being necessary to keep the chain from coming off the rear sprocket. Well, the chain is under tension from the rear sprocket to the countershaft sprocket when it passes under the roller. I don't see how the chain could flop about under tension. The "bottom" of the chain (as it travels from the countershaft sprocket to the rear sprocket) would be flapping about because it's NOT under tension.

Second, regarding second-guessing Suzuki engineers... I'm old enough to have ridden in (and, amazingly enough driven) the old Ford Pintos. You know, the ones that could EXPLODE if rear-ended! It was YEARS before Ford finally admitted there was a problem.

I wouldn't remove the "lower" rollers (by the rear sprocket). THOSE actually make sense. But that upper one? I just don't see its purpose.

Next time I speak with Jesse, I'll have to ask him about throwing the chain since I've seen it happen on the "bottom" (see above) of the chain, not the top.

Share this post


Link to post
Share on other sites
With 12 full posts under your belt I can how "I don't (think) there is any reason for concern" is logical to you. Try the search function, once you learn how to use it, and you will see there is a concern. Since you say "I'm not going to second guess the engineers at Suz." Why are you saying "I think the condition for a failure is a fully bottomed out shock" Isn't that statement saying the Suzuki engineers did not do their job since every engineer knows someone will allways take it to the limit? :thumbsup:

I have only 12 posts, now 13, so I’m not too smart. The logic here is you get smarter with each post. I should let this go, however I want my PhD! :)

Seriously, yes people will always take it to the limit. This doesn’t enable them to push that limit and not expect a failure. Do you rev your engine to the red line every shift? Cause that’s the limit! Would you then expect the engine to last?

When the engine smokes, is that the engineers fault? He didn't do his job? As an engineer, given all adjustments are within their correct limits you design within the parameters of “expected normal use” not extremes, that’s what racing bikes are for. We all know how long they last and they were designed for pushing the limits.

If the rider is bottoming out the shock and the chain is loose what failure would you expect to see? If the chain is too tight and the shock is bottomed out, what failure do you expect to see?

So to those of us with brand new bikes and only 12 posts we should assume everyone of these failures posted; the chain was properly lubricated and adjusted and the sprockets weren’t worn. If that is truly the conditions for these failures I am very surprised; Suzuki not only hasn’t done something about it, but they haven’t even heard of the failure.

Unless you examine each failure, and those specific conditions they occurred under it’s just conclusions based on speculation. Yes, engineer’s like everyone else make mistakes, and this could be one of those. But I’m not convinced based on what I’ve read.

This a functional part of your bike. Do you really know all the dynamics of the suspension and the effects on the chain under all conditions? Why was this function added to the bike? Was there some condition the engineer was trying to avoid? I don’t pretend to know this stuff, I don’t design motorcycle chassis. Do you?

These failures that are reported here, there is no real information to conclude what the root cause was. The result is the same, but you can’t begin removing everything that breaks thinking that was the cause.

I’ve provided my cents, and will no doubt get lots of change back. No worries, you guys with all the posts can have the last educated word on this. Good day!

Share this post


Link to post
Share on other sites

All i can say is I've done some frame bottoming jumps and keep a decent amount of slack in my chain and I've never had a problem blowing out the roller. I did however skipped out on the locktite when I put my roller back on after the screw that was in the upper threads was getting beat. I think I'll be getting another roller to keep control of the chain movement. I can see where a tight chain could cuase problems though.

Of course, I did have my chain pop off after a big jump which did some pre-damage to my case busting chain removal.

Share this post


Link to post
Share on other sites

First things first...The rollers do not come pre-grooved. The original roller only had grooves after riding it, and the Jesse roller also came smooth and only got grooves in it from riding. Those grooves indicate some serious and continued contact between the roller and the chain.

My bike is factory lowered, and I do not know if that contributed to the roller breaking off. I replaced the original roller with a Jesse one, and at that time I did not notice that the weld was shoody or poorly done. My bike has been used 95% on road, and the offraod was dirt/gravel roads.

To bring this post full circle: I am having my frame hole welded tomorrow. I was tired of waiting for my shop to get approval from Suzuki, and I figured that if they replaced the frame, I would be bikeless for at least 4 weeks. I will get the hole fixed, and ride rollerless.

Share this post


Link to post
Share on other sites
The grooves that are found on the roller; please note how uniform they are, same depth all the way around, as if the roller were formed with them from the tool that created them. These grooves are meant to be there and do not indicate wear. Look at a brand new bike they have grooves too. The grooves serve a purpose, as does this chain guide. I'm not going to second guess the engineers at Suz. as to the need for this. There is most likely a better after market part, but to remove it without any regard to it's function... ahh I don't think I want to travel on that slippery slope.

If the weld is weak then that is something different. Suz should have published a notice on it. My weld looks fine unless there are cracks under the paint. That condition could be true anywhere on the frame.

I think the condition for a failure is a fully bottomed out shock. Unless you are jumping the bike with the stock spring, I don't there is any reason for concern.

My rollers have no grooves what so ever. I have 564 miles on my dr650. I have one nick in the top roller and watch them both everyday. If you want pics, I'll gladly show you how mine look. I'm a newb as well, but I learned not to be "matter of fact" with the dr650 no matter what any entity tells you. Each bike is different and unique in it's own way.:thumbsup:

Share this post


Link to post
Share on other sites

My rollers were both heavily grooved.

The chain is most likely to contact the upper roller with the suspension compressed and with the drive train under load.

I could feel a real buzzing through the footpegs 2-up through bumps on a sealed road which hasn't happened since I removed the roller.

You've got about 37 odd hp pushing you along and if you compress the suspension up (about 3/4 of the way will do it) under load you've got all those horsies trying to pull the chain straight and that little bushed roller sitting in the road.

Share this post


Link to post
Share on other sites

The upper chain roller is the DR's own doohicky.

Each real bike deserves its own.

Share this post


Link to post
Share on other sites

SO, has anyone removed the shock linckage and raised the rear wheel with the top of the chain tight to see if the chain is contacting the roller when the suspension is compressed under acceleration, or if the chain is getting on top of the roller when the bike is decelerating and the top of the chain is slack and ripping the roller off as the suspension is rebounding?

I hope I said that so everyone understands.

If the chain is contacting the roller when the top of the chain is tight then it need to come off. If it getting on top of the roller when the top of the chain is slack and doing the damage when the suspension is rebounding the the roller needs to be wider.

My $0.02

Share this post


Link to post
Share on other sites

You don't need to remove the linkage. Just smear a dab of fresh grease on the upper roller and take a ride around the block. If you see toothmarks in the grease or fresh grease on your chain you know enough.

Share this post


Link to post
Share on other sites

I have removed my top roller, but I am curious, has anyone removed the bottom roller? Is it a problem as well?

Share this post


Link to post
Share on other sites

The bottom roller is no problem. It does tend to rattle though. If you hate that sound you can replace it with a roller that has bearings ( I did). Jesse from Kientech will gladly sell you one.

Share this post


Link to post
Share on other sites
I have only 12 posts, now 13, so I’m not too smart. The logic here is you get smarter with each post. I should let this go, however I want my PhD! :)

:thumbsup:

Seriously, yes people will always take it to the limit. This doesn’t enable them to push that limit and not expect a failure. Do you rev your engine to the red line every shift? Cause that’s the limit! Would you then expect the engine to last?

When the engine smokes, is that the engineers fault? He didn't do his job? As an engineer, given all adjustments are within their correct limits you design within the parameters of “expected normal use” not extremes, that’s what racing bikes are for. We all know how long they last and they were designed for pushing the limits.

All good points. But the advertised travel of the rear suspension is X. It's logical all travel within that range should be engineered for right? Just like red line, you shouldn't have catastrophic failures if you run your engine up to red line every shift. Sure, the engine is going to wear faster but is should not explode with minimal miles.

If the rider is bottoming out the shock and the chain is loose what failure would you expect to see? If the chain is too tight and the shock is bottomed out, what failure do you expect to see?

So to those of us with brand new bikes and only 12 posts we should assume everyone of these failures posted; the chain was properly lubricated and adjusted and the sprockets weren’t worn. If that is truly the conditions for these failures I am very surprised; Suzuki not only hasn’t done something about it, but they haven’t even heard of the failure.

Unless you examine each failure, and those specific conditions they occurred under it’s just conclusions based on speculation. Yes, engineer’s like everyone else make mistakes, and this could be one of those. But I’m not convinced based on what I’ve read.

This a functional part of your bike. Do you really know all the dynamics of the suspension and the effects on the chain under all conditions? Why was this function added to the bike? Was there some condition the engineer was trying to avoid? I don’t pretend to know this stuff, I don’t design motorcycle chassis. Do you?

These failures that are reported here, there is no real information to conclude what the root cause was. The result is the same, but you can’t begin removing everything that breaks thinking that was the cause.

I’ve provided my cents, and will no doubt get lots of change back. No worries, you guys with all the posts can have the last educated word on this. Good day!

Most of the items posted on this forum are experience based. That's kinda the idea I think. Sure, not everyone maintains their equipment to the same level as next guy. I'm certainly not going to assume all the reported incidents of this problem where reported by someone who poorly maintains their bike. Which brings me to another point. Take a look at your bike. If you compress the rear suspension to the point all 3 axis involved, countershaft sprocket, swing arm pivot and rear axle, are in a straight line you'll see that the chain has not yet reached the upper roller. In my non engineering mind this eliminates an over tightened chain as the cause of these failures because the well know "the longest distance between three points is a straight line", when it comes to a motorcycle chain anyway, would have the chain already starting to loosen up. Again, just my non engineering observation. It seems to me the most abuse this roller takes is from engine torque with increasing leverage force as the suspension compresses. All of which should have been engineered for by Suzuki. IMHO Suzuki made a boo boo in the structure, which includes proper welding, required to take these forces. Others on the forum are convinced as well because of gapping holes in their frames. Of course you can choose to assume Suzuki engineers are water walkers. I'm going with proven experiences and what my logic tells me in this case. :thumbsup:

Lets ride! :ride:

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this  

×