Author Topic: Four speed gear box thread  (Read 4328 times)

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Offline Michael Scott

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Four speed gear box thread
« on: 29 Apr 2008 at 13:42 »
Could any one tell me what the thread on the kick start end of the main shaft in a four speed gear (1930) is?
It is 20tpi and the od I get with my trusty mic is 0.455 inches

Chris's very useful complilation does not have it and he tells me that he does not have one to inspect

Michael

Offline Chris

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Re: Four speed gear box thread
« Reply #1 on: 07 May 2008 at 17:30 »
     To help out another member who has lost parts of his kickstart mechanism on the road during a run, I have just stripped off the parts from my CW to take some dimensions etc. and find that the left hand thread on the end of the gearbox shaft retaining the ratchet mechanism is the same as that measured by Mike for the four speed box. I actually made it 0.453"x 20tpi. I wonder if this is another Douglas Special as this corresponds with 29/64". Chris.

Offline Michael Scott

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Re: Four speed gear box thread
« Reply #2 on: 09 May 2008 at 11:06 »
   .... have just stripped off the parts from my CW to take some dimensions etc. and find that the left hand thread on the end of the gearbox shaft retaining the ratchet mechanism is the same as that measured by Mike for the four speed box. I actually made it 0.453"x 20tpi. I wonder if this is another Douglas Special as this corresponds with 29/64". Chris.

Thanks -.  will consider this over the weekend
michael

Edit 09/05/2008: Quite tags modified. A.
« Last Edit: 09 May 2008 at 12:42 by alwyn »

Offline trevorp

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Re: Four speed gear box thread
« Reply #3 on: 11 May 2008 at 08:06 »
.445 in some categories is 5/16 but cant find 20 tpi anywhere must be a douglas special

 

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