Hi Roy,
Look at TWO posts I made on this site last month. 1. Clutch fixed and Box Hill visited. and 2. Oil leal in the clutch housing. Both are in general discussion area. You are doing exactly what I had to do. I replaced the engine oil seal, THEN rebuilt it without doing the gearbox seals. Stupid move by me!! More leaking oil. It managed to run down the 'push rod' from the very back seal and spray it about the clutch. I cleaned the NEW one that I had replaced using CLUTCH CLEANER not petrol. I think...note I think...it has worked. I did get a hint of it slipping again a couple of weeks ago. B****cks I thought, but thing since as I have ridden it with care. I hope that it has cleaned itself.
I have bee told it only takes a few drops of oil on the plate to cause slip. I belive it now.
REPLACE all the bits in one go. Expensive yes (thats why I cleaned the new clutch plate when I had to open it all again. It had only been used for 150kms). The wear on the parts I replaced seemed very very little to the eye, but the effect was dramatic. The old clutch plate had looked good for a few thousand more miles. Spring, plates replaced and it was like new. Fantastic. Take real care on getting the spring holding the internal rubber boot (or gaiter) on properly. It had come off on mine and almost sawn through the shaft at the other end!! I could not get hold of a second hand one, which suprised me, so I had to buy a new BMW one. £££'s. But good to know that you can get them, arrived in 24 hours.
Have a look at my posts, and good luck. Boris the Bike

Hi BTB,

Thank you for this advice. Excuse me for asking the obviouse for it is first time I ever did anything mechanical), but:

1) How many seals are there for the transmision assembly?
2) Must I disturb the transmission box? I am a little intimidated with messing in this box.
3) What other clutch bits specificaly do you recommand I replace? I must admit you surprised me as they all seem quit good after being cleaned up. Will clutch need rebalancing?
4) Any ideas on original post concerning driveshaft?

Thank you
Roy

Roy

Hi and welcome to the forum. First off if you havent got one get a repair manual. I recently did a rebuild of my drive system and stripped down the gearbox only to find that it was cheaper by at least 75% when I sourced a good 2nd hand gearbox (complete) which I got from beemerboneyard than the cost just for the output shaft and 5th Helical gear alone and have no idea what a gearbox housing would have cost. Subsequently though the Haynes manual has a step by step description on overhauling most bike components. You can buy a service kit which off memory there were 7 bearings and 4 or 5 seals. Anyway getting back to your original question of the pinion input spline for the final drive unit like you found that Brunos do not do overseas repairs (australia) and I ended up sourcing another good 2nd hand complete final drive unit. The only suggestion would be to go to a local machine engineering shop that cuts gearing or splines and see if they can rebuild and recut the spline on the shaft. On the download section here the K1100 factory workshop manual shows basically how to pull the final drive unit apart and you will need a specialised socket to undo the locking ring which will no doubt make repairing the spline a lot easier. My original final drive is quite good except for the spline which is fairly well worn after some 250,000 klms. Anyway hope this helps your enquiry.

Hi,

I have since replaced the eng main seal (see posting here) and clutch friction plate and reasambled clutch and trans in place.

My gearboc seemed Ok and for now I hope I do not have to invest in it. But the rear splines on shaft and the rear drive splines are bad. I am now examining my options between rebuilt and new as no 2nd hand ones came up in net.

Because of custom taxes best would be to get a 2nd hand in good condition then a refurbished one and finnaly a new one as for new the tax can be 50%.

I am still working out my options.

Hi Roy,
Sorry not to have got back sooner. Been sailing....If it would help, I would be very happy to purchase a new drive shaft here in the UK and organise mailing it to you as a "pressie". May save on ther 50% tax! I had to buy one about a month ago, it was about £120.00. Not cheap, but brand spanking new without ANY worn splines. As to rebuilding the clutch. I was very careful about marking it as I took it apart. This was unnessessary since I replaced all the spinning bits and followed the BMW painted marks. Set them at 120 degrees and it should be OK. Roys is very right about a manual, get one. Haynes is good but not perfect. Also find a friend that understands mechanics, it does NOT have to be a BMW or even motorbike mechanic, just a friend that is a keen amateur. There is a LOT of common sense involved that crosses over from any experience with engines. I found that the seals and clutch plate look fine, but when replaced solved a huge amount. SEALS are cheap and cause a lot of damage if they leak....Ask away for help, I'm back on line again.
Cheers Boris the Bike

Hi BTB,

I actualy do have Haynes and Clymer and they do compliment each other. These plus the info in the forums is very good. However, I must be the slowest mechanic in the universe - before this I basicaly recognized there is a wheel at each end and that the noisy thing in the middle must be the engine. However I am having a great deal of fun understanding (slowely..) what goes where and why.

I am reasonably sure my oil leak was ONLY eng oil and no trans oil because over a period of time trans oil level did not go down at all while eng oil very definetly did. this was over 3 seperate times.

The cost you got for shaft is better then I found anywhere, does this source have rear drives as well?
Your offer is very kind and we can discuss this OOB.

What you say makes a lot of sense, yet for now I only replaced the friction plate - I did not have any clutch issues that I was aware off.

tnx
Roy

Hi Roy,
got your note, will get back later. BTB