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koofruff key keeps breaking
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I'm fairly new to bike restoration so could do with a bit of help.
The bike I'm working on is a 1936 Sokol, which is a Polish built
knockoff
that is basically a 995cc Vtwin a la Indian combined with Harley front
suspension.
The problem is that the woodruff key on the kickstart keeps breaking.
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The woodruff key is supposed to break to protect the engine internals in
the event of an excessive mechanical shock. If it's breaking in the event
of
a normal mechanical shock then check:
1) should be zero lubrication on the keyed shaft
2) key should not be normally taking any shear load
3) key must fit exactly, make sure the slot where the key goes is not
hogged out, or the key isn't too small, etc.
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The engine starts fairly easily with no appreciable kick back. The
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Is the kickstarter shaft tapered? In that case, the tapered parts may
be worn out, allowing the rotational load to be on the key instead of
the tapered parts which are supposed to carry the load.
At one time, Husqvarna countershafts were pressed onto a tapered
countershaft...
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If you use genuine parts, then it could be that the key is too hard.
I once owned a russian Ural (sorry ;-) that had parts as hard as
glass (valve stems, dynamo axle'among other). Fabrication standards
simply were no good.
Those parts broke under load.
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If you use genuine parts, then it could be that the key is too hard.
I once owned a russian Ural (sorry ;-) that had parts as hard as
glass (valve stems, dynamo axle'among other). Fabrication standards
simply were no good.
Those parts broke under load.
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If you use genuine parts, then it could be that the key is too hard.
I once owned a russian Ural (sorry ;-) that had parts as hard as
glass (valve stems, dynamo axle'among other). Fabrication standards
simply were no good.
Those parts broke under load.
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If you use genuine parts, then it could be that the key is too hard.
I once owned a russian Ural (sorry ;-) that had parts as hard as
glass (valve stems, dynamo axle'among other). Fabrication standards
simply were no good.
Those parts broke under load.
|
|
If you use genuine parts, then it could be that the key is too hard.
I once owned a russian Ural (sorry ;-) that had parts as hard as
glass (valve stems, dynamo axle'among other). Fabrication standards
simply were no good.
Those parts broke under load.
|
|
If you use genuine parts, then it could be that the key is too hard.
I once owned a russian Ural (sorry ;-) that had parts as hard as
glass (valve stems, dynamo axle'among other). Fabrication standards
simply were no good.
Those parts broke under load.
|
|
If you use genuine parts, then it could be that the key is too hard.
I once owned a russian Ural (sorry ;-) that had parts as hard as
glass (valve stems, dynamo axle'among other). Fabrication standards
simply were no good.
Those parts broke under load.
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advance/retard mechanism of the distributor has been screwed down in
the maximum retard position and will stay like that until I can
fabricate the cable for the manual mechanism.
I'm reluctant to keep on making new keys until I understand why they
keep breaking.
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