Author Topic: Gearbox plunger  (Read 191 times)

Offline Superflash

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Gearbox plunger
« on: 20.03. 2021 22:39 »
So mucking about with the gear box due to it jamming up. First drama sorted when I discovered that I was missing 2 washers. 1 behind the 1st gear pinion and the other behind the kick start spring. One thing I noticed was that the plunger has what I'd describe as a bullet tip. Looking at the parts drawing it looks more like a blade tip. To me the bladed one would give a more positive engagement with the cam plate. So.... leave well enough alone or change it for one of the bladed one? Cheers
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Online Greybeard

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Re: Gearbox plunger
« Reply #1 on: 20.03. 2021 22:54 »
My 1955 sprung frame bike's gearbox has a bullet shaped detent plunger, (I don't know if that snippet of information helps)  *smile*

Offline Superflash

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Re: Gearbox plunger
« Reply #2 on: 21.03. 2021 00:07 »
Cheers GB. I guess if it works then that's fine.  I just wondered if the bladed one was a design mod that worked a bit better than the bullet type.  Cheers Tony
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Offline trevinoz

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Re: Gearbox plunger
« Reply #3 on: 21.03. 2021 21:00 »
I think that the blade type plunger was in the early boxes. I have one here in pieces.

Online Minto

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Re: Gearbox plunger
« Reply #4 on: 21.03. 2021 21:43 »
Sorry to butt in but, what does this plunger actually do? I know that's a novice, schoolboy question, but that's what I am.
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Online berger

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Re: Gearbox plunger
« Reply #5 on: 21.03. 2021 22:29 »
minto it is spring loaded and provides pressure into the cam plate valleys at each gear change to hold the selector forks in position, if the pressure wasn't there you have a very good chance it will jump out of gear

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Re: Gearbox plunger
« Reply #6 on: 21.03. 2021 22:43 »

Online Minto

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Re: Gearbox plunger
« Reply #7 on: 22.03. 2021 00:56 »
Cheers for that, every day's a school day.
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