speaking of doohickey - torsion spring?

[Charles (Service Informatique Gosford)]

Hi all, I had a vibration problem on my KLR. It would vibrate a lot, but mostly around 5K RPM and above, wich rendered the bike uncomfortable on the highway. I researched a lot on the internet about that and the end conclusion of that research was that for a single cylinder, it was normal. I lived with it for a while, then rode a friend's KLR. It was smooth! Well, it did vibrate a little, but not nearly as much as mine. I bought the Clymer shop manual. For those who don't have it, you should buy it. The KLR is a pretty simple machine to work on, but the manual has a lot of details that make troubleshooting a lot easier. I found a page that mentionned the balancer synchronization. Basically, there are 2 balancers that are connected to the crankshaft through a chain (the chain that the Doohickey puts tension on) and act as counterweight to minimize the vibration caused by a single cylinder 4 stroke engine. Those balancers need to be synchronized with the crankshaft in order to cancel the vibration. In pure despair, I opened up the left side cover (make sure you put your piston at TDC before you do so if you want to check correctly) and took a look. IT WAS OFF! As far as I know, nobody did any work there that could have caused that, so it must have been out of factory. I synchronized everything and went for a test ride..... FIXED!!! I cannot believe it. I did everything possible on that bike to solve that problem, carburetor, valve adjustment, valve timing..... heavy bar ends and so and so, and it was a factory adjustment problem in the engine! I love the KLR, but I was thinking of selling it for something smoother.... not anymore! Happy riding to everyone! Charles

[Jud Jones]

--- In DSN_KLR650@yahoogroups.com, "Charles (Service Informatique Gosford)" wrote:

> > Hi all, > > I had a vibration problem on my KLR. It would vibrate a lot, but mostly > around 5K RPM and above, wich rendered the bike uncomfortable on the > highway. I researched a lot on the internet about that and the end > conclusion of that research was that for a single cylinder, it was > normal. I lived with it for a while, then rode a friend's KLR. It was > smooth! Well, it did vibrate a little, but not nearly as much as mine. > > I bought the Clymer shop manual. For those who don't have it, you > should buy it. The KLR is a pretty simple machine to work on, but the > manual has a lot of details that make troubleshooting a lot easier. I > found a page that mentionned the balancer synchronization. Basically, > there are 2 balancers that are connected to the crankshaft through a > chain (the chain that the Doohickey puts tension on) and act as > counterweight to minimize the vibration caused by a single cylinder 4 > stroke engine. Those balancers need to be synchronized with the > crankshaft in order to cancel the vibration. In pure despair, I opened > up the left side cover (make sure you put your piston at TDC before you > do so if you want to check correctly) and took a look. IT WAS OFF! As > far as I know, nobody did any work there that could have caused that, so > it must have been out of factory. I synchronized everything and went > for a test ride..... FIXED!!! I cannot believe it. I did everything > possible on that bike to solve that problem, carburetor, valve > adjustment, valve timing..... heavy bar ends and so and so, and it was > a factory adjustment problem in the engine! >

You would not be the first guy that has happened to.

[Thor Lancelot Simon]

On Sun, Mar 11, 2007 at 11:32:22AM -0400, Charles (Service Informatique Gosford) wrote:

> > crankshaft in order to cancel the vibration. In pure despair, I opened > up the left side cover (make sure you put your piston at TDC before you > do so if you want to check correctly) and took a look. IT WAS OFF!

This isn't all that uncommon. One sign that it could be the case with a particular KLR is if the vibration gets slightly _worse_ when the balancer adjustment is done every few thousands of miles. This might actually be worth putting in the FAQ.

[revmaaatin]

--- In DSN_KLR650@yahoogroups.com, "Charles (Service Informatique Gosford)" wrote:

> > Hi all, > > I had a vibration problem on my KLR. It would vibrate a lot, but

mostly

> around 5K RPM and above, wich rendered the bike uncomfortable on

the

> highway.

SNIP

> Charles

Charles, Good work on finding your problem. Remembering what I have gleaned from list-wisdom, another source-vibration is 1)loose, under torqued engine mounts (including the upper ones under the tank) and a 2) chain that is way to tight, which also manifests itself as 'surging'. Apparently, it was not either of these problems! revmaaatin.

[Jon Neet]

Good job on figuring out the reak cause of the vibrations. Mine must not be out of time because the last time I "adjusted" the balancer tensioner, it really smoothed out the engine. jon in puyallup --------------------------------- Looking for earth-friendly autos? Browse Top Cars by "Green Rating" at Yahoo! Autos' Green Center. [Non-text portions of this message have been removed]

[Norm Keller]

Guess this means we have another task as part of the Doo' replacement. That's an easy time to do the check which (at that point) is a "why not?" Thanks for the heads up, Norm [Non-text portions of this message have been removed]

[Mike]

--- In DSN_KLR650@yahoogroups.com, "Norm Keller" wrote:

> > Guess this means we have another task as part of the Doo'

replacement. That's an easy time to do the check which (at that point) is a "why not?"

> > Thanks for the heads up, > > Norm > > [Non-text portions of this message have been removed] >

There might be a couple of things to consider as one does this. The sprockets have 18 teeth, so for every revolution of the cranshaft the chain will advance 18 links, right? The chain has 70 links, so the marked links on the chain will not line up every revolution of the engine (to TDC), or every revolution of the chain. IIRC, it take 9 revolutions of the chain for all to correctly line up again. (it's late and I have a headache) You can do the math as well as I, I'm sure. Least common multiple, right? Also - remember the bolts holding the chain guides on are made of compressed oatmeal, and loctited with red loctite. Heat is your friend if you need to remove the bolts. all the best, Mike

[Charles (Service Informatique Gosford)]

Hi Mike, You are right about that, if you look at the marks on the chain and the lineup with the gear, it might take a couple of revolution to line up properly. A good indicator are the marks on the sprocket. I compared the small alignment dots on my sprockets and where they were pointing with the picture in the shop manual and they were way off. But you are right, the chain alone doesn't tell everything . As for the chain guides, I had no problem at all removing them and no locktite was there. May be somebody did it before I did....

> > There might be a couple of things to consider as one does this. The > sprockets have 18 teeth, so for every revolution of the cranshaft the > chain will advance 18 links, right? The chain has 70 links, so the > marked links on the chain will not line up every revolution of the > engine (to TDC), or every revolution of the chain. IIRC, it take 9 > revolutions of the chain for all to correctly line up again. (it's > late and I have a headache) You can do the math as well as I, I'm > sure. Least common multiple, right? > >

[Blake Sobiloff]

On Mar 11, 2007, at 8:32 AM, Charles (Service Informatique Gosford) wrote:

> I had a vibration problem on my KLR. It would vibrate a lot, but > mostly > around 5K RPM and above, wich rendered the bike uncomfortable on the > highway.

Very interesting to hear, Charles! I have a similar complaint, with a bad vibration in the right footpeg at 5K RPM. My answer to date has been to use the passenger footpegs for long highway stints, or to wear my motocross boots. I've been wanting to give the torsion spring doohickey a try, so I may do the same balancer synchronization check while I'm in there and see if my bike's similarly mis-adjusted. Thanks for the tip! -- Blake Sobiloff http://sobiloff.typepad.com/blakeblog/> http://sobiloff.typepad.com/klr_adventure/> San Jose, CA (USA) [Non-text portions of this message have been removed]

[E.L. Green]

--- In DSN_KLR650@yahoogroups.com, Blake Sobiloff wrote:

> On Mar 11, 2007, at 8:32 AM, Charles (Service Informatique Gosford) > wrote: > > I had a vibration problem on my KLR. It would vibrate a lot, but > > mostly > > around 5K RPM and above, wich rendered the bike uncomfortable on the > > highway.. > > I've been wanting to give the torsion spring doohickey a try, so I > may do the same balancer synchronization check while I'm in there and > see if my bike's similarly mis-adjusted.

Hey Blake! I did the balancer synchronization check/fix when I did my doohickey, but it didn't help much, if at all. My bike still vibrates at high rpm's. I just view it as a foot massage and ignore it . Looking at the mechanism, I just have to shake my head. This is no way to design a balancer mechanism. The problem is that it really isn't adjustable. The balancers on a lot of other bikes are adjustable so that you can move the weights slightly fore or aft to find the "sweet spot" that exactly counteracts the thrashing of the piston at your typical cruising rpm. With the KLR mechanism, you can only jump entire teeth, which is way too granular to do a real adjustment. As the chain wears and the guides wear, the whole mechanism slowly drifts, and there's no real way to "fix" it short of replacing major parts or doing some major machine shop work. For those of us with high-mileage bikes, putting up with some vibration seems to be pretty much a given, because the mechanism simply lacks the adjustability to compensate for normal wear and tear. _E