Clutch housing (mirror LH thread)
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Pierre Michaud
Clutch housing (mirror LH thread)
Why is the thread on the handlebar clutch housing Left handed? Please do not answer "because the mirror stem is threaded that way"! I just purchased an insert (LH) to repair the bad threads on the housing I have. The original threads on my housing are right handed. Every document I have read says the threads are LH! Why are my threads RH then?
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Mark Huggett
Re: Clutch housing (mirror LH thread)
Pierre,
A LH thread for the mirror mount on the clutch lever armature is not uncommon and is found on many machines, Japanese and continental alike. The old fashioned rear view mirror on a motorcycle offers a great deal of wind resistance. If the right hand side mirror had a RH thread in the clutch lever armature, the continous buffeting from the wind while riding would have the tendency to continuously loosen the mirror. I have made this experience on some or other bike with a RH thread on the RH rear view mirror, and the damned thing kept on loosening by its self. Damned frustrating!
Regards,
Mark
Mark Huggett GmbH
A LH thread for the mirror mount on the clutch lever armature is not uncommon and is found on many machines, Japanese and continental alike. The old fashioned rear view mirror on a motorcycle offers a great deal of wind resistance. If the right hand side mirror had a RH thread in the clutch lever armature, the continous buffeting from the wind while riding would have the tendency to continuously loosen the mirror. I have made this experience on some or other bike with a RH thread on the RH rear view mirror, and the damned thing kept on loosening by its self. Damned frustrating!
Regards,
Mark
Mark Huggett GmbH
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Pierre Michaud
Re: Clutch housing (mirror LH thread)
Mark,
Thanks for explanation. It makes good sense. When did BMW stop turning out clutch castings with mirror RH thread then, as mine (1967) is RH threaded?
Thanks for explanation. It makes good sense. When did BMW stop turning out clutch castings with mirror RH thread then, as mine (1967) is RH threaded?
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Mark Huggett
Re: Clutch housing (mirror LH thread)
Hi Pierre
I'm not sure when BMW stopped the LH thread in the clutch armature, but it must have been some time in the early seventies possibly with the /6 series. It was a continuous problem with the thread stripping in the zinc casting so Magura eventually just drilled a hole right through the housing were the lever is slotted into, and locked the mirror in place with a lock nut on the underside, and of course, a RH thread.
Regards,
Mark
Mark Huggett GmbH
I'm not sure when BMW stopped the LH thread in the clutch armature, but it must have been some time in the early seventies possibly with the /6 series. It was a continuous problem with the thread stripping in the zinc casting so Magura eventually just drilled a hole right through the housing were the lever is slotted into, and locked the mirror in place with a lock nut on the underside, and of course, a RH thread.
Regards,
Mark
Mark Huggett GmbH
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Pierre Michaud
Re: Clutch housing (mirror LH thread)
Mark,
I have a feeling from your description of the clutch casting that I do not have an original on my 1967 R69S. The clutch housing I have has a right hand thread and there is no recess underneath to fit a lock nut. Could it be a /5 or /6 casting? Also, the high and low switch has a knob similar to a horn button that you can push which I believe would actuate the flasher. This switch has two separate branches, one with 2 wires and the other with 3 wires. this does not agree with the wiring diagram I have. The part also looks newer than the switch on the front brake casting which lodges the turn signal/horn swivel switch. My instuction manual shows both switches to be identical to the turn swivel switch I have which looks the same age as the Motorcycle.
I have a feeling from your description of the clutch casting that I do not have an original on my 1967 R69S. The clutch housing I have has a right hand thread and there is no recess underneath to fit a lock nut. Could it be a /5 or /6 casting? Also, the high and low switch has a knob similar to a horn button that you can push which I believe would actuate the flasher. This switch has two separate branches, one with 2 wires and the other with 3 wires. this does not agree with the wiring diagram I have. The part also looks newer than the switch on the front brake casting which lodges the turn signal/horn swivel switch. My instuction manual shows both switches to be identical to the turn swivel switch I have which looks the same age as the Motorcycle.