Jump to content

V11 lemans drive shaft (wobble)


Bob LeClair

Recommended Posts

My 2002 lemans drive shaft has a wobble when turning and the splines were binding so that it wouldn't come apart. Had to use a scissor jack to separate them. Splines are fine, well greased, but would only slide together halfway before binding. Turns out it is bent, hence the bind. I did some judicious sanding and filing and now it has full travel. I went on a short ride and didn't notice any shake from the possible imbalance. It must be stated that I have never ridden the bike before, it was very not running when I got it, stored outside in the elements for several years and in need of serious attention. 

So now my question: what should I do about it? Try to get it straightened, replace it, or leave it? The misalignment is noticeable when turning though I have not miked it to see how far out it is. If it can't be straightened, does someone have a replacement? I want to sell it but I'm not comfortable with it as is. Thanks in advance for any input.

  • Like 1
Link to comment
Share on other sites

If it's bent, don't ride it fast or far. Just for "shake downs" no pun intended. The vibe will eventually blow out the uni joints. I saw a shaft from an '04 on ebay a short while back, low miles I recall. Hang in there, you'll get it sorted. You're in the right place.

  • Like 1
Link to comment
Share on other sites

Not sure how the hell a drive shaft gets bent but if it is then it's time for a new one I'd say. The only possible option would be a drive shaft specialist but most only tackle the car shafts they are used to dealing with. I personally would have a go at straightening it in a press if it wasn't too bad, but that's me. It's definitely bent is it, I mean if the shaft is full of grease it can stop the splines fully engaging from memory and the suction can make them hard to get apart, or am I dreaming again? I wouldn't be surprised if you stuck a runout gauge on a Guzzi shaft it would have .010"-.020" runout.

  ciao

  • Like 2
Link to comment
Share on other sites

What Puil said, if there's too much grease the shaft pieces wont compress until you let some grease out, I had to take the zirk off to let some out. Then learned not to grease the center zirk when the axle wheel not in place.

I have a nice used driveshaft complete from a Centauro . if you can determine they are the same, I'll sell it.

Link to comment
Share on other sites

The bend is noticable when you rotate the back wheel, maybe a eighth inch out of round. I found one at a shop that I ordered. Also noticed when I torque down the axle, the wheel is harder to turn than when the nut is loose. Normal or something else to worry about?

The swingarm is a snug fit between the pork chops, doesn't bind but zero clearance. I miked the pivot pins on both sides before dismantling, but there's no side to side play so why'd I have to mike the pins if there's no adjustment to be made? 

Link to comment
Share on other sites

On 3/20/2021 at 2:49 PM, Lucky Phil said:

Not sure how the hell a drive shaft gets bent but if it is then it's time for a new one I'd say. The only possible option would be a drive shaft specialist but most only tackle the car shafts they are used to dealing with. I personally would have a go at straightening it in a press if it wasn't too bad, but that's me. It's definitely bent is it, I mean if the shaft is full of grease it can stop the splines fully engaging from memory and the suction can make them hard to get apart, or am I dreaming again? I wouldn't be surprised if you stuck a runout gauge on a Guzzi shaft it would have .010"-.020" runout.

  ciao

I cleaned out the grease before trying to reassemble it, the splines bound up about halfway in.

  • Thanks 1
Link to comment
Share on other sites

On 3/20/2021 at 1:36 PM, footgoose said:

If it's bent, don't ride it fast or far. Just for "shake downs" no pun intended. The vibe will eventually blow out the uni joints. I saw a shaft from an '04 on ebay a short while back, low miles I recall. Hang in there, you'll get it sorted. You're in the right place.

I rode it about 10 miles, only up to about 50mph, didn't notice any shake, but I'm going to replace it anyway. I'm learning a lot about these machines from this project, and I like how they are relatively simple and straightforward to work on. 

  • Like 2
Link to comment
Share on other sites

23 minutes ago, Bob LeClair said:

The bend is noticable when you rotate the back wheel, maybe a eighth inch out of round. I found one at a shop that I ordered. Also noticed when I torque down the axle, the wheel is harder to turn than when the nut is loose. Normal or something else to worry about?

The swingarm is a snug fit between the pork chops, doesn't bind but zero clearance. I miked the pivot pins on both sides before dismantling, but there's no side to side play so why'd I have to mike the pins if there's no adjustment to be made? 

Re: rear axle. We've had instances of owners discovering that the rear wheel 'between the bearings spacer' was manufactured a tad bit short, causing it to eat bearings from lateral stress. Always a good idea to check bearings for notchy-ness every time the wheel is off. This 'could' cause the tightness you are referring to. There is a topic on it somewhere but once again, I can't find it

  • Like 1
Link to comment
Share on other sites

Click top title dated June 18, 2019, for one of the images of the placement of the bearings and spacers on the rear axle. Correct (113+ mm) spacer installed with the damaging (~112mm) spacer on the bench above the axle  . . .

 

  • Thanks 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...