Universal Joint - Alignment?


Like Newton - only stupid
UKGSer Subscriber
May 1, 2002
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Clinging to reality by a finger tip.
Can anyone tell me how the UJs' at either end of the drive shaft line up in relation to each other.

Is it the first or second picture or does it not matter?




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1st picture - yokes need to be 90 degrees opposed in order to avoid velocity variations when transmitting torque. Trust me - I'm pissed again!
2nd picture - ignore me, I'm pissed again, ignore the last post as well. In fact f()ck it, I'm going to bed. Is anybody still there?
I believe that Frank is correct.

Hooke Joints as they are properly called (named after Robert Hooke - same bloke as in Hooke's Law) is not a constant velocity joint. Unless the joint is running straight, a contant turning velocity of the input will give a varying turning velocity of the output. The usual way of correcting this is to have a second Hooke joint at the other end of the shaft aligned (as in picture 2) to reverse the effects.

The condition needed to ensure an equal input/output speed is to ensure that the angle between the input shaft and the Cardan Shaft is the same as the angle between the Cardan Shaft and the output shaft. This is usually done by ensuring that the input and output shafts are parallel (as in the GS), but an equal, but opposite, angle will also have the same effect thereby enabling a constant speed drive to be transmitted around a corner as it were.



My little tip!!
It looks good to me,now install it on the bike without the shaft housing and mark the rear piece of shaft that goes on the bevel input,and also mark the front piece with white paint or something thats easy to see,just a couple of dots will do,but make sure they line up exactly because you have to split it again before you can reinstall the shaft housing and then you can't see the front UJ once it is back on the bike,but now you have marked it you know exactly where it goes and will mirror the front UJ.I have found it easier to install the rear piece on the bevel pinion this way you can make sure the locating circlip inside the shaft is seated properly in the groove on the pinion shaft.Don't know if you knew this already,but thought I would post anyway.Andy
Thanks everyone.

Now to get to grips with the swingarm gaiter. I can see that providing hours of fun.


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If you put some WD40 around the gearbox end of the gaiter it will just slip on the flange easy do this before you put your pins back in this way you can just push the whole swing up to the back of the gearbox.Andy

Instead of Wd I used LM47 and it just shot back into place. Swingarm pivot pins are in place but not torqued or loctited 'cause I've got to go to work:( I'll do that tonight.

Thanks for your help.


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