Power Surge on Driveshafts

[doug m]

First off, hope everyones doing well, I haven't been around for quite a while. Just wondering if anyone else gets a power surge through the driveshaft, usually when on the power hard. It seems like the engine revs up quicker than the driveshaft can respond to the power. I know that there is a bit of power lash on driveshafts, but sometimes it is quite noticeable. Perhaps it is not the shaft, but clutch issues?

[Lucky Phil]

First off, hope everyones doing well, I haven't been around for quite a while. Just wondering if anyone else gets a power surge through the driveshaft, usually when on the power hard. It seems like the engine revs up quicker than the driveshaft can respond to the power. I know that there is a bit of power lash on driveshafts, but sometimes it is quite noticeable. I only notice this on my nero corsa, but not really an issue on the old sport.?

Its called clutch slip.Will be worse when accelerating hard in the upper gears,4th,5th.

Ciao

[mznyc]

Yup sounds like clutch slipping,how many miles on it?

[Craig]

First off, hope everyones doing well, I haven't been around for quite a while. Just wondering if anyone else gets a power surge through the driveshaft, usually when on the power hard. It seems like the engine revs up quicker than the driveshaft can respond to the power. I know that there is a bit of power lash on driveshafts, but sometimes it is quite noticeable. Perhaps it is not the shaft, but clutch issues?

 

 

Definitely a fried clutch. Some people that learned and spent lots of time on motorcycles with wet clutches (pretty much everything from Japan) like to slip clutches much more than they would in a car. Wet clutches can handle that. The MGs (and most BMWs and Ducatis) have a dry clutch which should be used like a car clutch: on or off with as little time as possible spent in between.

[mznyc]

Well I would say it "could" be worn clutch plates but not "definite" without further investigation.

First thing you could do is look through the timing inspection hole,or better yet remove starter and look for fluid.There are two seals in there,one for the engine oil,one for the transmission fluid.If fluid gets on the plates,they'll slip.Also if the clutch MC fluid hasn't been flushed for a while you can try changing that and see if it helps,unlikely but worth a shot if the housing looks dry inside.

If you have to change the plates it involves pulling the transmission or engine,which I did a few months ago.Not a huge job but you'll need parts and tools and a way to lift the bike.(A simple hydraulic lift and a factory rear stand will do)About a day or two depending on your ability,experience,tool selection and if you have help.

Let us know what you find,if it is the plates ,a good winter project!

Michael

[LowRyter]

I know when I am riding aggressively and upshift from 3rd to 4th that it kind of sticks & lurches. Just a slight delay and jerk. don't know why it does it. sorta fun too.

 

dont want to hurt it

[mznyc]

I know when I am riding aggressively and upshift from 3rd to 4th that it kind of sticks & lurches. Just a slight delay and jerk. don't know why it does it. sorta fun too.

 

dont want to hurt it

That sounds like a fueling issue.

[doug m]

Well I would say it "could" be worn clutch plates but not "definite" without further investigation.

First thing you could do is look through the timing inspection hole,or better yet remove starter and look for fluid.There are two seals in there,one for the engine oil,one for the transmission fluid.If fluid gets on the plates,they'll slip.Also if the clutch MC fluid hasn't been flushed for a while you can try changing that and see if it helps,unlikely but worth a shot if the housing looks dry inside.

If you have to change the plates it involves pulling the transmission or engine,which I did a few months ago.Not a huge job but you'll need parts and tools and a way to lift the bike.(A simple hydraulic lift and a factory rear stand will do)About a day or two depending on your ability,experience,tool selection and if you have help.

Let us know what you find,if it is the plates ,a good winter project!

Michael

 

There are about 20,000 kms on the bike. I am usually not to hard on the clutch,so I am a little surprised it is going away already. I will take your good advice and check into it and will post what I find when I have some time to get to it. My gamma motor has been sitting on the bench for a few months now, waiting for a reinstall, and I have to get to that as well...sigh. Too many bikes and too little time.....ah well, things could be worse. I'll have to quit my job and just work on my bikes full time .......I wish! Thanks again for everyones input,,Doug

[mznyc]

 

There are about 20,000 kms on the bike. I am usually not to hard on the clutch,so I am a little surprised it is going away already. I will take your good advice and check into it and will post what I find when I have some time to get to it. My gamma motor has been sitting on the bench for a few months now, waiting for a reinstall, and I have to get to that as well...sigh. Too many bikes and too little time.....ah well, things could be worse. I'll have to quit my job and just work on my bikes full time .......I wish! Thanks again for everyones input,,Doug

No I wouldn't think at 20K they would be worn.Maybe a leak,Would amount to the same labor as doin the clutch cause you have to pull the clutch to get the rear seal on the block.They dont blow very often but we've seen a few here.If it's not a leak or plates,Im sure one of the residents experts may offer a guess.I have the tools for the clutch job and transmission lock nut if you have to do it.

I hear ya about multiple bikes,not enough time.I got a couple big projects in the queue now that the Scura's back on the road.

[kglm]

Just replaced a leaking engine sealring ( no slipping with that ) to new one. Clutch plates totally dry and measured 7.8 mm => back again.. 120tkm touring ride.

 

-KG-

[GuzziMoto]

There is also the crank case vent, which is there at the back of the block. That can leak and the oil can make its way on to the clutch plates.

But there would likely be a small drip at the bottom of the clutch bell housing.

[LowRyter]

I know when I am riding aggressively and upshift from 3rd to 4th that it kind of sticks & lurches. Just a slight delay and jerk. don't know why it does it. sorta fun too.

 

dont want to hurt it

That sounds like a fueling issue.

 

I think it's a jerky clutch egagement....but don't know why it's only 3rd to 4th.

[mznyc]

I know when I am riding aggressively and upshift from 3rd to 4th that it kind of sticks & lurches. Just a slight delay and jerk. don't know why it does it. sorta fun too.

 

dont want to hurt it

That sounds like a fueling issue.

 

I think it's a jerky clutch egagement....but don't know why it's only 3rd to 4th.

Ya that's weird that it only does it in one gear.I had missed shifts and false neutrals for a while,changed,clutch fluid,played with the eccentric nut,(the bike's not mine),changed trans fluid,replaced clutch and it turned out to be a bad pre-selector assembly.Got a used one on ebay and voila it shifts.So ya could be one of several possibilities.

MG fun

[LowRyter]

I know when I am riding aggressively and upshift from 3rd to 4th that it kind of sticks & lurches. Just a slight delay and jerk. don't know why it does it. sorta fun too.

 

dont want to hurt it

That sounds like a fueling issue.

 

I think it's a jerky clutch egagement....but don't know why it's only 3rd to 4th.

 

prolly cause I was goosen it hard there

[docc]

I know when I am riding aggressively and upshift from 3rd to 4th that it kind of sticks & lurches. Just a slight delay and jerk. don't know why it does it. sorta fun too.

 

dont want to hurt it

That sounds like a fueling issue.

+1 - Perhaps a good indication for a thorough tune-up (valve adjustment, plugs, TPS/ idle set, throttle body balance).

 

Worth a try!