I have an old Schlumpf mountain drive on a second hand bike which I would like to remove and refurbish before reusing. It has a torque arm on the right/drive side and a lockring with 4 indents for some kind of spanner on the left side.

As I've so far failed to get anything to move I have a couple of questions....

Is the lockring a normal thread or a left hand thread ?

What kind of spanner/tool do I need (and where can I obtain one) ?

If I manage to get it off can it be converted to use conical cups and not the torque arm ?

many thanks,

Eric

Hi Eric,

If you look on the Schlumpf website there is an excellent pdf giving step-by-step instructions on dismantling/servicing/fitting MDs. I don't remember off hand the direction of the thread - these things are generally fit-and-forget pieces of kit. Give me a shout if it isn't there any more. Just be careful not to damage the central shifting shaft when you are working on it.

We have a socket to fit the castellated ring available for loan for a £10 deposit plus p&p costs (it needs a 1/2in socket driver which some folk have around but is heavy and a pig to post).
We also stock the more standard toolkit/buttons should you need it.

Don't know about conversion from torque arm MD to conical version - I'd drop Florian an email - he speaks perfect English and is always very helpful.

Rob
Westcountry Recumbents
wrhpv.com

Rob,

Thanks for that, I've had another look on their website and now found the very useful PDF you mention. I did manage to remove the one surviving button and the cranks safely without damaging the shifter rod but now have to get the drive out of the bottom bracket shell. I may be in touch about the tool !

In case it helps any others - from the pdf manual.
'Please note: mountain-drive uses left-handed threading, the
speed- and high-speed-drive uses right-handed threading.'

Eric