K75C Driveshaft Question...

[Faghurts]

Hey yall,


So the other day my bike broke down in traffic so I had to trailer it home. I pulled it apart and the rear splines are gone...


I have attached some pictures of my findings. The splines on the driveshaft are undoubtedly done for, but what is your honest opinion on the final drive? It seems like they are in better far better shape than the splines on the driveshaft.


 It seems like I really can find any decent used parts for this thing, but I did find this:


http://www.ebay.com/itm/87-BMW-K100RT-Driveshaft-Drive-Shaft-Assy-U-Joint-OEM-K100-RT-RS/253077629394?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649


The splines are not ideal, but they do look like there is some life left?


I guess my real question is if I get the previously mentioned driveshaft does it appear that it will hold up with the splines on my final drive?


Furthermore, does anyone know of some nice used equipment that would be worthwhile?

I know that the parts are not ideal, but I wanna ride especially while the weather allows for it!!!


What da ya think?

[The Mighty Gryphon]

How many miles?  It looks like the splines have never been done, and as a result, even those on the final drive look to be toast.  Very bad news.

[Faghurts]

Its got 37k miles on it. I bought the bike about 2 months ago, put about 1500 on it since.

[Martin]

+1 Sorry I'm with Gryph looks like it's never been done. It should have been on the top of your list to do, not that it would of helped much.
Regards Martin.

[Faghurts]

Agreed. I was going to take a look at it, but didn't get to it in time.

[Faghurts]

I have been trying to find some nice used parts but can't seem to locate any. Do you guys know of any?

[SDCR john]

Honestly, I don't think doing it 1500 miles ago would have made any difference. That is a few years worth of neglect. Hope you can find some used parts, perhaps beemerboneyard has these reasonably.


 

Agreed. I was going to take a look at it, but didn't get to it in time.

[John Lang]

Your FD pinion splines are shot and will ruin the splines on any driveshaft attached to it in very short order. Beemer Boneyard had a FD (drum brake) and driveshaft in fair condition last time I looked. You really need a new FD pinion and an aftermarket DS from beemershop.com. Together, not cheap unfortunately.

[TX brick]

I see a lot of grease in the FD housing. Maybe the PO lubed with substandard grease. If so, it would be nice to what grease not to use.


I have enough GD 525 left for only a few more applications.

[Laitch]

Its got 37k miles on it. I bought the bike about 2 months ago, put about 1500 on it since.

You bought a used bike with neglected parts that failed. It appears they failed because they weren't properly lubed with the correct type and amount of lubricant. If you could have inspected them before you bought the bike, that might have helped but only if you understood what you saw. It's probably rare that a seller would even allow anyone to inspect a bike to that depth. It's a classic used vehicle story.

You'll be able to replace the parts if you search diligently and patiently for good quality replacements. You need to educate yourself on what they look like and there is plenty of information available here and elsewhere on the web.

[Faghurts]

Thanks guys!


So I ended up finding a used DS and FD off a wrecked bike on eBay.


The FD splines look like they are in great shape.


From what I can tell from the DS photo, the DS splines look in decent shape as well.

[Laitch]

So I ended up finding a used DS and FD off a wrecked bike on eBay.
The FD splines look like they are in great shape.

I can't tell whether they are any good from those photos. I would need a clear frontal profile and a clear overview closeup. My impression right now is that they are not in "great shape." Maybe I need a better attitude. :giggles

[Faghurts]

Ill try and get some more photos from the seller.


These are what I have right now.

[johnny]

greetings...

taking a close look at the clutch and trans splines would be my top priority before buying anything...

j o

[Faghurts]

OK,


I got the seller to send me a video of the splines.


https://www.youtube.com/watch?v=UrKdX4ckiCs&feature=youtu.be.


The video isn't the greatest, I think the seller is having a hard time getting a good shot.


To me, the FD splines look good, but I am sure about the DS splines.


If I opted for a new DS, does it seem like there would be the possibility of the FD splines wearing out the DS splines?


Or do you think the DS splines are ok to run?




On another note, I did find a FD (used) and DS from re-psycle. has anyone dealt with them? Are they a reputable dealer?

[johnny]

greetings...

re-psycle has been 100% pro...

look... you may wanna step back and think this out...  if you have not looked at the clutch trans splines you may need the whole shebang... which means you may have a parts moto in your possession or need to acquire a parts moto to fixt this one...

j o

[John Lang]

Here is a close-up of my FD splines just as they had finished off their DS buddies. I asked an expert whether there was any life in them and he said NO, they would destroy their mate within a few thousand miles. Your 'new' FD is in better shape than this one was so perhaps you could risk running it with a DS in similar or better condition but expect failure in the not distant future.

[kris]

Faghurts,
I hope these photos will help you draw a more accurate conclusion of where you sit with your splines. My bike has 68,592 miles on it and this is what my splines look like. The bike was, clearly, maintained throughout or I'm just one lucky guy.


Heed Johnny's point....if your final drive looks as bad as it does then you likely have other issues with your output shaft and clutch splines. Don't throw your money away. Check things out thoroughly.


Good luck.

[Faghurts]

Thank you all for your input, I do agree. I'll pull it apart this weekend and take a look at all the splines.

[Faghurts]

I took the bike apart this weekend. Not good.Clutch splines were COMPLETELY rounded out.Transmission splines, not as bad but not good.I am really surprised this thing even rode.

[Faghurts]

Trans splines

[Faghurts]

More shots

[gone_ape]

With regard to this not turning into a "looky here at my splines", but in an effort to show what something else looks like at a certain mileage,  this is the classic peak tooth at ~70k on the drive shaft and in my opinion, still serviceable.....the FD pinion appears ok for this mileage....  I acquired this bike at 68k and have no idea how it was maintained previously....

[gone_ape]

And at ~68k, the transmission input shaft...the shaft seal was leaking and if you look closely, you can see the seal was installed improperly somewhere back in time.....these splines were bad and because new shafts are very difficult to find, (and frankly, it's way more cost effective just to find a low mileage complete transmission replacement),
  I had to find a replacement serviceable transmission and a new clutch disk to fix it.....just so you can get an idea what to look for....