Aprilia sr125 Motard (Piaggio Typhoon) clutch dragging problem. [solved]

Hi folks.

Wonder if anyone has any experience of this.

My Aprilia SR125 Motard, 2013 model, is fighting to move off when stationary. If I put it on its stand when running, thr back wheel spins quite fast.

I've pulled it all apart and there is nothing obviously wrong. The bell on the clutch spins freely, the clutch springs all seem ok - the pads move out and back again when I lever them with a screwdriver. The pulley is quite difficult to pull apart, but it does split.

The belt looks OK, no fraying or obvious wear.

The variator is straight and clean, the only thing I can see is a slight flat spot on a couple of the rollers - is that likely to be the problem?

It runs pretty normally when moving - the acceleration etc is normal, top speed is not changed, its only when I slow down it just doesn't want to stop. I can hold it on the brakes, but that's obviously not ideal.

So, logic tells me, the clutch is engaging. That's the only way it can be trying to move. This suugests, as the clutch itself seems OK when the engine isn't runnig that the variator is spinning the clutch up too much when ticking over.

Before I go and spend a lot of money replacing the transmission parts ( without any guarantee it'll solve the problem), does anyone have any experience of this, or have any suggestions?

Thanks for your help!

 

I was thnking about exactly that this afternoon. I hadn't considered it could be the engine doing it, because holding it on the brakes would stop the engine revving up, but it would do exactly this.

I've turned the tickover down, and lubed the throttle cables and the gubbins around the carb, which was pretty grubby. I can't try it till tomorrow, but I'll report back.

I reckon It could also be a frayed throttle cable, so I'll order new ones tomorrow.

Thanks for the help, I'll report back.

 

Pop the air filter off the back of the carb and with a torch, see if the carb slide is dropping all the way back down when you release the throttle.
Like you say, it could be a frayed cable, or maybe some crap in the throttle housing, or simply that the end of the cable has popped out the housing.
No good ordering stuff until you know what the problem is.

 

OK, thanks. Will have a look at that tomorrow. Appreciate your advice.

 

The flat spots you mention on the rollers could also be the problem.
Or some crap on the variator ramps.
Flats could cause the rollers to not roll back to the bottom of the ramp, thereby still engaging the vario and clutch.
If you think about it, the rollers have to be thrown out for the clutch to engage, maybe the rollers are too light now they have some wear on them.

 

OK, to update.

It seems it is a throttle issue, not transmission. I wound the tickover right down yesterday, and cleaned up all the crap around the throttle assembly on the carb (spring, cable etc).

I rode it to work this morning, 17 miles and it was spot on all the way. Problem seems to have been solved.

I still don't know why it spontaneously decided to start doing this, it is now ticking over normally despite having been adjusted down. I can't see how the tickover could have been changed, it wasn't me.

Anyway, that's a relief, I have been using my old R1 for commuting, and I get about 28mpg from that.

Thanks all for your help!

 

Good news and thanks for posting the results.
You'd be surprised how many don't.
Nice to know it was a simple problem, solved, and no new parts bought.
You should use this lesson as part of the normal maintenance routine now.