Transmission Woes...

[azcycle]

I got married on Sunday, and have had a great few days off with my new wife.  It was our first day back to work this week, and she was running late, so I decided to take the r65 into work this morning.  It was a beautiful commute in... weather great, not too many crazy cagers. Then it happened....

I was about halfway to work, shifted to third, and when I let out the clutch I heard the most horrid grinding sound accompanied by NO power to the rear. Pulled in the clutch, shifted down to 2nd, let out the clutch with the same result..... *GRIND*

Coasted off onto a side road with my heart sinking. The bike seems to shift up and down okay, but when I release the clutch, it doesn't engage.... just a horrible grinding sound. I assume the clutch splines are stripped? I was a bad boy... and hadn't checked the clutch splines since I've had it. It was one on the "to do" list but maybe too late now...

So assuming this is the problem, what kind of $$ damage am I looking at here?  Ugh... great way to start off my marriage after completely emptying our bank account on the wedding. Looks like the r65 will be down for a long while until I can save up the funds.  

Is this John's way of saying he doesn't approve of me marrying his daughter?  I thought he liked me!  

[Lucky_Lou]

Have you checked the drive shaft bolts under the swinging arm boot?? may not be the splines if your lucky.....congrats on the wedding.
How about this just in case.
http://cgi.ebay.co.uk/BMW-R-series-5-speed-gearbox-1981-/150498033348?pt=UK_Motorcycle_Parts&hash=item230a61bec4

Lou

[azcycle]

Haven't checked anything. Left it in a parking lot and got a ride into work. I need to go back this evening with a truck and carry it home. Will check the drive shaft bolts when I get a chance.

[Bob_Roller]

Transmission input shaft is around $300, if you can just get away with labor to open the transmission up and replace the shaft and all of the seals and gaskets, add maybe around the same amount, if bearings need to be replaced, figure on around $600-700 for the transmission rebuild .

The clutch needs to be replaced around $100, if the pressure ring and pressure plate don't need to be replaced you'll save another $200 or so .

Figure in the rubber boots that will probably need to be replaced, bolts, lock washers and spline grease, figure on about another $50 .

It may be more cost effective to get a replacement transmission .

[montmil]

As to the above comments, check the easier and cheaper stuff first... Drive shaft bolts under the boot can be kinda checked by squeezing the boot and feeling the bolts as you rotate the rear wheel.

Pulling the swing arm pivot bolts and pulling back the transmission will reveal the input splines but you'll need to completely remove the gear box to check the female portion of the spline connection. Keep your fingers crossed, Graeme.

And congratulations and best wishes on your marriage. Hoping your new bride understands your BMW addiction. At least she'll know where you are... in the garage working on that *#@*!* money pit of a motorcycle.

I love it!

[azcycle]

I know she understands, as it was her dad's bike. She was all too familiar with his obsession with 2-wheeled BMW's. And I know she wants to do whatever it takes to keep this bike, as it "IS" her dad to her.  Might not be fixed immediately, but it will be fixed and back on the road eventually.

[montmil]

Graeme, Let us know what we can do to assist. You will not, repeat not, quit this bike. SWWBO deems it so.

[nhmaf]

Sounds very familiar to me - the info you need to pull the gearbox and change the clutch parts yourself is in our wiki section.

If you are VERY lucky, the input shaft splines on the gearbox won't be too badly damaged - but you'll have to be very lucky, and the more times you run the engine and try to enage the clutch will make things worse.   I still have my old transmission siting in the garage waiting to be repaired (new input shaft).  I was able to find a fully rebuilt transmission for $500 by careful scouting of the internet, so I bought that and put it in while I save the ~$600 or so it will likely take to ship and rebuild the original gearbox.

[azcycle]

Well, got the bike home tonight after dark. Didn't have much time or motivation to snoop, but I DID feel the driveshaft through the rubber boot and felt the driveshaft turn so that's not it. I reluctantly put the bike in gear and gently rolled it back and forth, listening, and could definitely hear what sounded like an angry bee "vvvvvvvvvvtttt.... vvvvvvvvvtttt" sound from right between the gearbox and engine.  So while I'm no expert and I won't crack the beast apart for a while yet, I'm pretty certain it's the input shaft splines. They sound pretty shredded.

[Rob Valdez 79 R65]

To remove the transmission, you will need to drop the swing-arm.
Those 27mm locknuts on the swing-arm pivots can be hard to get to.
Some 27mm sockets fit easily.  Most have to have their OD reduced a bit to fit in the recess.  You also want to "flatten" the rim to remove any taper, allowing the socket to get a good connection.

I just bought one of these for $13



http://www.culayer.com/Joes_tools.htm

For a long time, I used BMW's tool, but it doesn't allow you to check the torque.

[Lucky_Lou]

Graeme, Let us know what we can do to assist. You will not, repeat not, quit this bike. SWWBO deems it so.

interesting quote there Monte on this side of the pond its... SWMBO dare say you'll figure it out.
I hadn't read the eBay ad fully seems the price includes stripped splines thought it was cheap.
Lou

[azcycle]

I mentioned to the wife that rebuilds are typically in the $600 range and her response was "Oh, that's not too bad..." so while it's no small chunk of change, she is okay with it. Of course, while I'm in there I might have to replace the clutch and it will give me the opportunity to replace the badly leaking main seal (and/or oil pump cover).  So we might be looking at $1000 or so. Ugh.

So speaking of clutches, assuming this one does need to be replaced, do I have to buy ALL pieces or can I just get the clutch plate and/or the diaphragm spring? I read somewhere how they're balanced together a certain way so I have to purchase as a group? That seems expensive to do just to renew an intended replaceable item...

[Bob_Roller]

They are not balanced as a group .

I had the plates resurfaced and the friction lining replaced on my '81, three years ago .

I don't recommend going that route, I had nothing but problems with a poor machining job on the plates .

The two plates that mate up to the clutch, normally develop high and low spots with use, when you replace only the clutch disc,  I have been told that you can get rapid wear on the clutch disc and reduced life .

Check the plates when you get them off and see how 'true' they are and then make your decision .

[azcycle]

So I'm hearing some inconsistencies regarding gearbox rebuilds. It's mentioned here above that a rebuild is in the $600 range but on another forum they're saying at least $1600. I know it depends on the damage, but I can't fathom $1600 on a rebuild of the r65 gearbox.... maybe a newer model BMW.

Can you guys help clarify so I can remove my heart from my stomach?

[Bob_Roller]

A normal rebuild, which includes all of the gaskets, seals, shifter pawl spring and bearings is in the range of $650-700 including labor .

In your case, the input shaft is around $300 in additional cost .

So figure $950-1050 in your situation .