Re-fitting Final Drive

Beemerman59

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Started a 30K service today and thought while I was at it I would drop the FD and take out the pivit pins for a looksee. All went just fine and dandy, bearings are OK, little bit of surface rust on the driveshaft etc so moly'd up the splines and proceeded to but it back on. So how the hell are you supposed to line up the driveshaft with the fixed spline on the FD? There are few things I have worked on to get me to the point of throwing something across the garage but this is one of them. After four hours of struggling and what now seems to be a permanent pain in my left shoulder I finally struck on a brainwave. I put a loop of thin wire under the driveshaft so I wiggle it around until finally the spline's pushed home. Then I could pull the wire out from behind the gaitor to finally finish the job.

There must be an easier way. It's easy peezy on my K1100RS..........
 
It can be a little reluctant, but I've never struggled that much, you must be doing it wrong :D
 
Started a 30K service today and thought while I was at it I would drop the FD and take out the pivit pins for a looksee. All went just fine and dandy, bearings are OK, little bit of surface rust on the driveshaft etc so moly'd up the splines and proceeded to but it back on. So how the hell are you supposed to line up the driveshaft with the fixed spline on the FD? There are few things I have worked on to get me to the point of throwing something across the garage but this is one of them. After four hours of struggling and what now seems to be a permanent pain in my left shoulder I finally struck on a brainwave. I put a loop of thin wire under the driveshaft so I wiggle it around until finally the spline's pushed home. Then I could pull the wire out from behind the gaitor to finally finish the job.

There must be an easier way. It's easy peezy on my K1100RS..........

Yep the old wire under the driveshaft trick. You can lift the FD up against the driveshaft and then turn the FD backward and forward using the brake disc whilst applying slight pressure and it will go in. After about the third attempt I have it cracked.
 
I used a plastic cable tie to hold a length of string onto on my Diversion 900 UJ as there is only a 20mm hole to work through. When its fitted just cut the tie. Easy peasy that way, but virtually impossible without.
 
Yep the old wire under the driveshaft trick. You can lift the FD up against the driveshaft and then turn the FD backward and forward using the brake disc whilst applying slight pressure and it will go in. After about the third attempt I have it cracked.

I tried every which way to get it on including moving the splines with the brake disk but with the driveshaft sitting where it does unsupported I just couldn't get the right angle of attack. I even tried holding the entire FD without the pivot pins to try and line it up but no joy. Its quite heavy so lifting it as a dead weight and trying to line it up would only give me a few seconds each time. Anyway, now I know the wire trick I would give it ago again but still believe there's a better way.
 
done it loads of times never had a prob,one finger through the gaiter to line up uj and push fd up,support fd on knee so you can turn disc with hand to line splines up if needed,never taken me more than 30 to 40 seconds cable ties and wire just complicate a very simple operation i reckon
 
Beemerman are the bearings in your rear UJ free and easily moved? They should move freely in all planes Unlike Boirche's that only had 3 positions (before it was replaced)

I use the Proctologist method

Hold the concertina boot back a bit and offer up the fd to splines

a little leverage underneath with the proctological digit accompanied with a twist of the brake disc and hey presto they should mate most easily
 
I obviously need to learn the knack. It is very comforting to know that for some people its a doddle so I must also be able to do it quicker and easier. In fact, I will redo it every service so eventually I will be able to do it whilst drinking tea at the same time.

The driveshaft UJ's have very free movement in all planes both at the gearbox end and the FD plus there's no roughness in the FD itself which is also very comforting.

I was surprised how much water gets in there though - there was standing water at the bottom of the swingarm tunnel and surface corrosion on the driveshaft. I sprayed a load of ACF50 up there but will add this to my service schedule. I guess since BMW fitted a drain plug to the FD there's usually no need to take the FD off so I would think there are a lot of 1200's out there with all this going on out of sight and out of mind. I also covered the lower UJ's with grease for the this reason. Same with the pivot pins - I doubt that few people will bother to take the whole drive off to look at those and their associated bearings as their not on the service schedule.
 
done it loads of times never had a prob,one finger through the gaiter to line up uj and push fd up,support fd on knee so you can turn disc with hand to line splines up if needed,never taken me more than 30 to 40 seconds cable ties and wire just complicate a very simple operation i reckon

Thanks for the tip although at 6'3" and not being as supple I used to be I find it a little cramped underneath the bike to do all of this stuff. Will do better next time - promise :D
 
your suposed to use silicon grease i think to seal the gaiter to the housing when you have disturbed it,(i use copious amounts of red rubber grease and dont get water in me tunnel:D
 
your suposed to use silicon grease i think to seal the gaiter to the housing when you have disturbed it,(i use copious amounts of red rubber grease and dont get water in me tunnel:D

Yes I know - the water was in there before I took the FD off. Its supposed to be Staburags NBU 30 PTM which of course I didn't have so I used another grease I happened to have handy. Not sure its going to work though so may try and find a source of the Starburags or similar.
 
As I was so pissed of with myself and I hadn't refilled the FD with oil or torqued anything up, I decided to drop the FD and do it again. Yep, 30 seconds it is then. Just remember to put the gaitor on the FD end first not the swingarm :blast Still couldn't use my fingers to help so used the wire under the shaft but it went on easily. Pride restored!
 


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