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R60/5 Driveshaft

kentuvman

New member
:usa Happy 4th Gang! Enjoy your holiday!

My R60/5 has @ 80k on the clock (or so it says - found out my FD and Speedo are mis-matched - 37/11 W1155) So maybe not really 80k but who knows? She runs strong - all that matters to me.

So if I take off slow I'll get a rattle - clutch is new and tranny is strong - wondering . . . do the "U" joints wear out and if so, what is the RX?

Thanks again.:usa
 
I think there needs to be more information as to a "rattle". Do you have a sense where it's coming from? Same rattle in say 2nd gear? Only when taking off?

What service have you done on the drive train? Have you checked the four bolts that connect the shaft to the transmission?

U-joints do wear but it's not a common thing that I've heard.
 
The first thing I would do is to make sure that the bolts holding the U-joint to the transmission flange have not loosened themselves. Other things to check would be the swingarm pivots and maybe the long motor mount studs thru the frame. I have never experienced the rattle you describe, and I have never experienced a bad U-joint on an early airhead.
 
Thanks - the rattle only will occur if I let out the clutch fairly quickly in 1st - only 1st. If I keep adding throttle while letting out clutch, no rattle. No rattle in any other scenario - no other gears or when riding along.

Driveshaft bolts (no washers) are new and tight - used the rag & 10mm and pulled snug, and so are studs holding motor to frame. Will double check the DS bolts.
 
U-joints do go bad. What happens when you spin the rear wheel with the bike on the center stand? Hear any noises? What about when pushing it around the garage?
 
U-joints do go bad. What happens when you spin the rear wheel with
the bike on the center stand? Hear any noises? What about when pushing it around the garage?

I'll check - maybe an oversize rear tire as it won't spin on C/S but will push around garage and listen. Thinking it could be the D/S - once owned a Volvo 122s and when U joints went bad it had a similar rattle noise coming out the chute from stop to go in 1st.
 
Just thinking here . . . if rear tire IS oversized, wouldn't that put more pressure on D/S when taking off? Size of tire is 110-90-18
 
A 110/90 is not THAT oversized...it's still an 18" tire, just wider than normal. Now if it were a 19 or 20 inch tire...that's tall and would need more oomph to move it. I don't think that's the issue. How's the clutch cable adjustment? Did you use the "Tom Cutter" method? Maybe you're getting imperfect slippage and the disk/pressure plate are bouncing until they seat.

You said you let out fairly quicly in 1st. What happens if you feather it in more? If it doesn't rattle, then I'd change your method of engagement in first.
 
Won't spin with the bike in neutral on the center stand??

Nope but front tire, 100/90/19 does spin freely on c/s.

If I feather clutch from stop to go, no rattle. Maybe Kurt is correct - could be new clutch hasn't seated yet and IIRC I lost my sharpee markings when I R&R the clutch.
 
You are lifting the rear off the ground when you try to spin it, right? If you are and it still does not spin, something is definitely wrong.
 
You are lifting the rear off the ground when you try to spin it, right? If you are and it still does not spin, something is definitely wrong.

What I'm saying is rear tire won't spin on centerstand - I'm sure if a helper lifts the rear rack, it will spin.
 
Yes, of course it won't spin if it's on the ground. You can kneel or sit behind the bike, push up on the rack with one hand and spin with the other. If it rattles, I would suspect a worn U-joint.
 
- maybe an oversize rear tire as it won't spin on C/S but will push around garage and listen.

Slip a scrap of 1/2" or 3/4" plywood under the centerstand. Depending on the size you may have to mess around with the position of the wood so that as you rotate the bike up it won't slip off. It's a bit of a grunt single-handed so having a buddy to help wouldn't hurt. Once it's up, rotate the bike onto it's front tire and slip something under the oil pan to keep the rear tire off of the ground.

edit - as you can see, it doesn't take a whole lot of "thickness" to get the tire off of the ground. A chunk of 1/2" ply should be more than enough.

project4s.jpg
 
Slip a scrap of 1/2" or 3/4" plywood under the centerstand. Depending on the size you may have to mess around with the position of the wood so that as you rotate the bike up it won't slip off. It's a bit of a grunt single-handed so having a buddy to help wouldn't hurt.

I've found that if I roll the front tire up onto a small piece 2x6 or 2x12 first, then slip the piece of wood (I use a 2x4) under the centerstand, it's not as much of a grunt to get it up and over. It then easy to remove the wood under the front tire and you can rock the bike forward if necessary...it will settle to the back naturally.

BTW...often wondered this but never tried it out...if you have the bike on the centerstand, the center of gravity is behind the centerstand. If you remove the rear tire, does the center of gravity shift in front of the centerstand? :dunno
 
As I recall, the last time I had my rear wheel assembly off it was just about on the CG (or only very slightly ahead of the center stand). I had the bike on one these small HF lifts. Since the center stand has to be up prior to lifting the bike (to get the lift under the oil pan) it means the weight of the center stand is shifted aft. But even with that extra weight behind the center stand pivot the bike still had a tendency (with the rear wheel off) to want to rotate forward. But not by much. I had a buddy with me as a "guard".

23422d1195913851-motorcycle-lift-lift.gif
 
I dont want to add to your anxiety but you might consider looking at the thrust rod..

Thanks - the rattle only will occur if I let out the clutch fairly quickly in 1st - only 1st. If I keep adding throttle while letting out clutch, no rattle. No rattle in any other scenario - no other gears or when riding along.

Driveshaft bolts (no washers) are new and tight - used the rag & 10mm and pulled snug, and so are studs holding motor to frame. Will double check the DS bolts.
This is kind of a long shot Ken but since you did some clutch work recently, you had the transmission out and you may have a broken thrust rod. I've seen a couple over the years and one recently on an 77 R100RS. The rods are held in close tolerance in the bore through the transmission output shaft and cant "go anywhere" so if they break, they make some noise for a bit till both ends wear into a sort of fit (usually one wears convex and the other concave and they will then run for a while without too much trouble. The noise you would hear from a broken thrust rod is like a snapping sound as the uneven ends 'cam' over each other when you pull or release the clutch and it is amplified by the transmission gear chamber. When the ends wear in, the noise goes away. The adjustment to compensate is minor. The two piece rod pictured was removed from a bike with 56K and may have run like this for up to 10 of those K.
 

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Thanks, John

I'm all but certain the U joints have slop - the thrust rod was in great shape other than a slight rattle if taking off too quickly, the bike runs amazingly smooth - this is the most "stately" of my (3) beemers, R65LS and K75s.

Are the U joints serviceable?
 
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