Vintage BMW Motorcycle Owners

Hi there.

I bought an 1960-R50 ( VIN 563502 ) about 3yrs ago.

The engine needed some repairs,
so, I contact Mark Huggett, and bought new pistons ( R50/2 ),
valves and everything to make the engine brand new again.

I'm not a mechanic, so I leave the bike on a harley mechanic here in Brazil.
( Note: Unfortunately, I don't know any BMW specialist back here )

So everything went fine

but, on my second ride,
I note that when I accelerate the bike,
seems the clutch was "slipping". and the bike loses the "traction"

And, when I send back to mechanic we noted the problem was not on the clutch, but on the Shaft and the flange. ( see the pics )

And now, I don't know what to do,
because if I change the Shaft and Flange
it can happen again.

Does anyone have some problem like that?

Thank you in advance for any help.

my best.
Rodrigo

Rodrigo -

Welcome to the forum! Sorry for your troubles. As I understand it, that is a tapered shaft and the flange has a matching taper. If these tapers don't match and also if they are not absolutely clean and dry upon installation, then there can be a separation. It's very important to have them clean and that the right torque is applied upon installation.

If the scoring is not too bad - you may be able to mate the tapers using valve grinding paste. You will know it will work when the match wants to bind together when they are both perfectly clean and are just pushed together by hand and are then hard to get apart.

These trial are sent to test us and make us stronger - which is another way of saying they are a real pain.

Hope it goes well for you.


Mal

That damage is way beyond repair. You will have to replace both the shaft and flange. If the tapers are in perfect condition, and the joint is torqued correctly, it will make for a really strong connection. Even small marks and scores will have a large impact on the joint strenght. Be aware that there are two versions of the shaft and flange. One has a 1:5 tapet and a keyway, one is 1:6 taper and no keyway.

I am going to undertake the exact same job myself on my R60 within a few weeks. Mine has the 1:5 taper and a broken key.

I know just what you are feeling.... the same thing happened to me on my first bike... that was lots of years ago and it was really hard to locate the parts then... Brazil probably does not have lots of spare BMW parts... luckily you have us.... hopefully one of us can help with the parts you need... I know I have several transmissions and I will look at them for good parts for you... That is not such an uncommon problem that BMW bikes suffer...so do not feel bad...

Joel

Guys, thank you so much for your help.

I was wondering,

They have 2 types of shaft, 1:5 taped and a keyway,
and other 1:6 tapper and no keyway - I think mine is this model, dont have a keyway.

So,
Do you know if
the BMW engeniers changed the shaft with no keyway
for the keyway model on the new motorcycles, because they spot that problem?

If they did that,
Can I change my shaft for a keyway model?

Maybe, this woud be an improvement on my motorcycle.

Or it's better keep the original?

Thank you again

My Best
Rodrigo

If you can,source the newer style with key,and get the matching set. You can find them on ebay.com or ebay.de .Good thing is that you have choice of parts from R50/R60/R69S since they are all the same.

Both will work,just make sure to get the matching set,you can find them on ebay.com or ebay.de .Good thing is that you have choice of parts from R50/R60/R69S since they are all the same.