Little help diagnosing

[Jethro]

I think my transmission might be shot.

Here is what has been happening. After about a a half hour of riding, I start getting a grinding noise when I let off the throttle. Maybe I just can't notice it when I am under throttle, but It is pretty distinct. I also clunks into gear really bad. Sometimes, after it's hot, I have a really hard time getting into neutral and from there to first. I put it up on the center stand and put it in gear and let the idle turn the rear wheel. Every once in a while, it clunks real bad and the chain jumps around. I had to put a rock in front of the front wheel because when it clunks, it is so bad the whole bike jumps, even on the center stand.

So maybe you guys can answer a few questions I have:

1. When the bike is off, on the center stand and in gear, I can turn the rear wheel so that the travel of the rubber is about 3 or 4 inches. This amount changes somewhat in each gear. Is this a bad thing?

2. Are there bushings and or bearings that are replaceable in our transmissions? Is anything adjustable or rebuildable or is it just worn out gears that need replacing?

3. What kind of job is it to pull the transmission? I assume I need to pull the motor out.

I hope the bike isn't dead, I just put a lot of money in to it last year. Oh, it has about 37,000 miles on the stock tranny. Thanks!

[SqDancerLynn1]

The first thing is too CHECK the chain real good. CHeck the front bearing for play. Otherwise trans work requires splitting the cases

[lhanscom]

It really sounds clutch related to me, is it disengaging completly? Maybe the clutch hub? The clutch is a whole lot easier to deal with then the rest of the tranny.

[Jethro]

The first thing is too CHECK the chain real good. CHeck the front bearing for play. Otherwise trans work requires splitting the cases

Chain tension is good, other than my rear wheel or sprocket is a little weird. The chain gets a little tight, then loose through the revolution. It must be the new cheap rear sprocket I bought. But I can gaurentee that it is not enough to be the real problem here. There is absolutely no play in the front sprocket.

It really sounds clutch related to me, is it disengaging completly? Maybe the clutch hub? The clutch is a whole lot easier to deal with then the rest of the tranny.

The clutch was out and rebuilt last year. All clutch plates and fibers were replaced, as well as the springs. Everything looks good in there, I think. Still, when the bike gets warm, it's a bit@h to shift into the low gears and neutral.

So, I take it I should pull the clutch and have a look. What should I pay attention to?

[Anonymous]

You've got a tight spot in your chain.It hasn't worn evenly,so best get a new one.

[bybowtie]

you may just have worn sprocket/chain,I'd start there.. Its seems as if they may have been slightly misalligned and have progressively gotten worn....

[earlfor]

My interpretation is that you replaced the rear sprocket, but did not replace the front sprocket or the chain. If correct, then...................BIG MISTAKE and a NO NO. Its a good bet shifting is difficult because of uneven chain tracking and tension at various degrees of revolution of the sprockets. I suspect the sprockets now dont fit the chain correctly. A worn chain will wear out sprockets faster than you can believe. I think you need new chain, and BOTH sprockets. Dont buy cheap chain! It will only last about 1/4 as long as a decent chain and you will be buying 4 times as many chains and sprocket sets in the long run. Better to buy one $125 chain and $50 sprocket set than have to buy four $75 chains and 4 $50 sprocket sets.

I put decent chain and sprockets on my 1150E (15,000 miles ago) and I only adjust my chain at wearing out rear tires. :-)
Its been on the same adjustment marks for 10,000 miles. eh eh

Earl


[quote="Jethro"]

Chain tension is good, other than my rear wheel or sprocket is a little weird. The chain gets a little tight, then loose through the revolution. It must be the new cheap rear sprocket I bought. But I can gaurentee that it is not enough to be the real problem here. There is absolutely no play in the front sprocket.

[Jethro]

Both sprokets and chain are fairly new. Im pretty sure it is not the chain. Something to note is that it doesn't happen every revolution of the chain, but like every 10 seconds or something. Maybe I will take a movie of what is happening and try to post it on my web page. I guarentee it is something internal. If I were to take the chain off, and put it in gear, I am pretty sure it would clank and grind. In fact, I'm gonna try that one right now.

[Jethro]

My interpretation is that you replaced the rear sprocket, but did not replace the front sprocket or the chain. If correct, then...................BIG MISTAKE and a NO NO.

No, not the case. I used to manage a cycleing shop for years. I would never replace the sprokets without the chain.

It's not the chain or the sprockets. I'm sure of it. They are all new, front, rear and chain. But I think the rear sprocket I got is junk, because there is a problem with the tension changing. It may be the wheel itslef too, I noticed that the inner hub (it is seperate from the wheel itself for some reason??) seems to be wobbling a bit.

[Jethro]

Dont buy cheap chain!

The chain is a killer double sealed o-ring DID chain. Top of the line.

[earlfor]

I had that symptom on my 750 once after swapping the rear mag out with another complete rear setup. It turned out the problem was caused by an unevenly worn cushion drive in the new wheel assembly. I swapped the drive rubbers from the old wheel (that ran smooth) and the problem went away.

Earl

[quote="Jethro"]
Something to note is that it doesn't happen every revolution of the chain, but like every 10 seconds or something.

[SqDancerLynn1]

quote Chain tension is good, other than my rear wheel or sprocket is a little weird. The chain gets a little tight, then loose through the revolution. It must be the new cheap rear sprocket I bought

NO MATTER WHAT YOU SAY ABOUT THE CHAIN something is wrong with it the tension should NOT change. You need new sprockets and chain replacement

[Jethro]

NO MATTER WHAT YOU SAY ABOUT THE CHAIN something is wrong with it the tension should NOT change. You need new sprockets and chain replacement

Maybe you guys can explain this cush drive in the wheel? I'm still not convinced it's my new chain and sprockets. Reason is, there is wobble at the seam of the wheel hub and the rim that matches where the chain gets tight. When I pulled the wheel off to replace the tire I was suprised to see the hub coming apart- shouldn't this be a solid piece? Why would this happen? What is this cush drive and how does it work?

[Jethro]

Would getting it hot make the cush drive not work as well?

[earlfor]

The cushion drive takes up the shock loads and helps to smooth out the drivetrain. However, the bearings and axle are what hold the alignment of the rear wheel. If the rear wheel is out of alignment and the tracking isnt straight, that is a bearing problem. If the rear wheel has a jerky movement to it, it can be worn out rubber inserts (cushion drive) in the rear wheel. It is rare though that they wear enough for that to happen. The sprocket portion of the hub is supposed to slide off the axle and on the inside surface you will see fins that slop into the cushion driver rubbers.
a little play is normal. A lot of play is not.

I would take the chain off, and inspect it link by link to be sure there are no stiff pins or binding links. Frequently, jerky chain operation is caused by seized pins. This can happen on a almost new chain. Another prime reason for chain wear and seized pins (besides lack of lubricant) is excessive chain tension. A chain requires NO tension to operate properly.
The top run of the chain is in tension from the countershaft sprocket pulling on it. That is the part of the chain that propels the bike. The drive tension alone is all that is required to seat the chain into the sprocket teeth. The only reason to put tension on the chain is to take vibration out of the unloaded return (bottom run) of the chain and to insure the chain is not so loose as to be able to throw itself off the sprocket. Although, I have never heard of a loosely tensioned (neglected) chain throwing itself off a sprocket. Overtightening a chain, increases heat build up an causes chain stretch, which makes the chain loose again. Too many people see that and retighten the chain and of course, it stretches back to loose again. A couple stretches and the pin to pin distance become greater than the tooth to tooth distance on the sprocket. Sprockets wear out, causes chain to heat up, stretches more, gets hotter, pins seize, and the drive train become jerky and noisy and the clutch ceases to work smoothly because the drivetrain is constantly backlashing at the clutch. As already said, pull the chain off and stretching it out a hard as you can by hand, see if it wsraps perfectly and smoothly around at least half of the rear sprocket teeth. If there is even one link that doesnt match up perfectly at the end of a half sprocket tensioned wrap, than your chain is trashed........and the sprockets also. Shiny new looks mean nothing.

When I tension a chain, I do it with the bike sitting on the centerstand. I leave 2 1/2 to 3" or movement available in the lower run of the chain. that means the chain can be lifted 3" above center and 3" below center.
When I take the bike off the centerstand and sit on it, my weight reduces the free play to 1 1/2 to 2 inches above and the same below center on the bottom run of the chain. That is as tight as you want a chain. I have not needed to change the adjustment of my chain on the 1150 in the time I have worn out three rear tires.

Earl

Maybe you guys can explain this cush drive in the wheel? I'm still not convinced it's my new chain and sprockets. Reason is, there is wobble at the seam of the wheel hub and the rim that matches where the chain gets tight. When I pulled the wheel off to replace the tire I was suprised to see the hub coming apart- shouldn't this be a solid piece? Why would this happen? What is this cush drive and how does it work?