Drive train issue

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Stephan D

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I'm having a problem with my drive train / transmission

There are two symptoms but I'm not certain if they're caused by the same issue.

1) Sometimes when the bike is parked, it won't roll freely even if it's neutral, like it's frozen in place.
When I put it in gear and move, it feels as though the wheels snap free after being frozen in place.

2) Early when I start to ride (doesn't happen later when the bike is warm): If I linger in the friction zone with minimal power to the wheel, there's a clunk clunking sound, as if slipping and catching a couple of times. Feels like it could be the transmission, shaft, or differential.

Some possibilities: I recently replaced the entire rear drive with a used replacement because I had a broken pinion. There's a possibility that the differential has an issue. I also don't know if there's a possibility that it was poorly installed (insufficient oil? shaft connection loose?)

Another possibility: I had a new clutch kit installed including plates, because the transmission was slipping under heavy load. The mechanic wasn't stellar (he was fiddling for 10 minutes with the clip & cover until another mechanic showed him how to close it). Could this be an issue with the new clutch / friction plates not performing as they should?)

Thoughts?
 

02GF74

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Before midnightmax says it, there is no differential but a pinion/crownwheel rear drive.

If it were rear drive, then surely you will get clunking all the time when moving?

2 things were done: rear drive replaced followed by the clutch, correct? Did this start after the RR or clutch, or maybe you did not notice.

Can you put the bike on the centre stand and exercise the clutch and rear drive to attempt to identify where the noise is coming from?

Can you turn the rear wheel wheel easily by hand when in neutral on the centre stand?
 

Fire-medic

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What kinda-shape were the rubber wedges in the rear wheel like? If they're worn-out that could cause clunking and a loose feel in the rear wheel.
 

Stephan D

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What kinda-shape were the rubber wedges in the rear wheel like? If they're worn-out that could cause clunking and a loose feel in the rear wheel.

I don't think so, the sound has more of a metallic/mechanical feel. The tire is in reasonably good shape.

PS / Edit: I think I might have misunderstood, I'm not sure what the wedges in question are. Is this part of the wheel itself? the rim?
 
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Stephan D

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If it were rear drive, then surely you will get clunking all the time when moving?

So it must not be the rear drive :)
The issue is occasional

2 things were done: rear drive replaced followed by the clutch, correct? Did this start after the RR or clutch, or maybe you did not notice.

Correct & I'm not really sure, maybe I did not notice immediately. But I have a feel that the occasional "stuck" rear wheel might have preceded both repairs, while the slow-speed noise is very recent. Not sure if it's an old problem that keeps deteriorating and showing new symptoms, or if there are two separate problems.

Can you put the bike on the centre stand and exercise the clutch and rear drive to attempt to identify where the noise is coming from?
Can you turn the rear wheel wheel easily by hand when in neutral on the centre stand?

Both issues are occasional - Next time the bike feels "stuck", I'll raise it & confirm that the rear wheel is stuck. But the noise is kindof unpredictable, it only happens sometimes, early when I start riding, if I'm showing off by going super slow on a street corner to let pedestrians through. Think "slow race" :)
 

gentsvmax

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What kinda-shape were the rubber wedges in the rear wheel like? If they're worn-out that could cause clunking and a loose feel in the rear wheel.
Good call F.M.
I had a backlash/take-up, quiet kind of slop issue.
I opened up the rear drive to see the beat-up, worn out wedgies
as the culprits of the slop.
 

02GF74

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So it must not be the rear drive :)
It's hard to diagnose at a distance but that's my guess so cannot be ruled out.

May be worth dropping the rear drive oil to see if there are metallic particles in it.
 

Stephan D

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Good call F.M.
I had a backlash/take-up, quiet kind of slop issue.
I opened up the rear drive to see the beat-up, worn out wedgies
as the culprits of the slop.

Hi - still trying to understand what F.M. said about the "rubber wedges in the rear wheel" ... are these rubber wedges in question inside the drive?
Thanks
 

02GF74

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Rubber wedges, known as cush drive.

The wheel has segments in which the cush rubbers sit, the driven flange has paddles (for want of a better term) that engage in the slots.

Basically the driven paddles press on the rubber that in turn presses on the wheel, this is to absorb shock.

Photo below show the cush rubber (not a vmax wheel) The gaps in the rubber accept paddles cast in the driving flange.
Screenshot_20210707-142056.jpg
 

02GF74

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OK, here is Vmax arrangement. A set of rubber bushes that engage with round pegs, the principle remains the same (wasn't that a Led Zep album?)
DSC_1470.jpg
 

Fire-medic

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One of the brake calibers locking up maybe? Just another thought...
Overheated brakes, you usually smell the roasted pads.

And I have a question, are you speaking of the .22, .38, .44, or .45's?
 

MaxMidnight

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Before midnightmax says it, there is no differential but a pinion/crownwheel rear drive.

Thank you. :D

Stephen, If the bike won't move in neutral then I would of thought that would rule out anything to do with the clutch.
I don't recall ever reading of an issue with the cush drive on a Max but as the rear wheel will need to come out it is easy to check.

The way you describe the problem I would suspect a bearing of perhaps U/J issue.
Did the problem manifest after you replaced the final drive (;)) or before?

If before then I would be starting at the middle gear and if after the final drive.
 

Stephan D

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Thank you. :D

Stephen, If the bike won't move in neutral then I would of thought that would rule out anything to do with the clutch.
I don't recall ever reading of an issue with the cush drive on a Max but as the rear wheel will need to come out it is easy to check.

The way you describe the problem I would suspect a bearing of perhaps U/J issue.
Did the problem manifest after you replaced the final drive (;)) or before?

If before then I would be starting at the middle gear and if after the final drive.

Thanks... I think the "stuck" problem precedes the final drive :) replacement - I just showed it to a mechanic, and his best guess is that the rear caliper needs to be cleaned. I need to replace the pads anyway, so if it turns out to be something else I'll post an update. Thanks again for all the help.
 

DreamV4

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One of the brake calibers locking up maybe? Just another thought...
I was going to type that!!! 😁
Recently I paid $20 to some smart guy, who told me that my Durango lost front caliper bolt, causing knock and rim scratching. Obviously I was not smart enough to figure it out myself...:(
Stephan, Do you need his tel #?😁
 

Stephan D

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Thanks - The "stuck" issue seems to have disappeared lately, I'm pretty sure is was a stuck caliper causing it. As for the clanking in the friction zone, I'll get the drive checked out next time I'm getting the rear tire changed, and take it from there.

Stephan, Do you need his tel #?😁
I'm not sure, is he in NYC? I could use a good mechanic who works fast.

... I would suspect a bearing of perhaps U/J issue.
At the risk of sounding some sort of way... What's a U/J issue?
 

Parminio

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02GF74

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Is the Vmax known to have troublesome UJ? I would expect it to be lubricated by oil splash so factory fitted UJ should outlastt he rest of the bike.
 

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