My experience wtih the gearbox (quadrant spring)

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madsundaysurvivor
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My experience wtih the gearbox (quadrant spring)

Post by madsundaysurvivor » Tue Jan 29, 2019 2:02 pm

I would like tell you my experience setting de gearbox, in case that the solution to my problems can help someone.

I had a gearbox without shimming washers, I had heard about the jump out in third whit the pre-69 camplate and like mine was a junk (see the photoI decided buy a new 69-on camplate and other parts:

-Camplate 69-on
-Selector fork or camplate 69
- Camplate spring
- Selector fork shaft (the original was worn)
- Quadrant pluger spring
- All the whasers in all sizes
- And some bushes for worn.

The fist adjusment was the camplante with its spring, I have had grind the lobe between 4th and 3rd, it touch the sping and not leave rest good the 3rd Groove.
Afther I was testing the shimming whasers, until all the gear worked well.
After many tries in dry, the gear don't engage all good, I had to turn the lever a few in opisite my purpose, then I could hear a small click (the plunger get in the camplante window)
why?
Then I decided check to camplate again. The a Windows was a few closer that the OEM, but only a few thous, this coludn't be the problem.
For trying things, I assemble the complete gearbox in the cases with the old gearchange quadrant spring and surprisingly all the gear engage very good :shock:
I couln't mount the old spring, was too deteriorated. Why my new spring didn't work well?
Then I saw that my spring was too strong and turn the quadrant a few degrees respect it neutral position.
Finally the solutión has been to bend a bit a spring leg, and the quadrant has been complety perpendicular to the camplate.
I'm sorry it's very difficult for me to explain in your language
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Ian Hingley
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Re: My experience wtih the gearbox (quadrant spring)

Post by Ian Hingley » Tue Jan 29, 2019 6:39 pm

madsundaysurvivor wrote:
Tue Jan 29, 2019 2:02 pm
I'm sorry it's very difficult for me to explain in your language
Hey MSS

Your English is perfectly good enough for us to understand what you mean!

I've never thought about quadrant spring trying to twist the quadrant. Who knew BSA gearboxes were built to such fine tolerances? ;-)

Glad you've got it sorted. :thumb

That camplate!
Never seen one anything like that one. Someone must have had a "very heavy right foot". (That's how legendary rally driver Ari Vatanen described himself)

Cheers

Ian
Last edited by Ian Hingley on Tue Jan 29, 2019 7:46 pm, edited 1 time in total.
66 BSA Victor Enduro, 72 BSA Lightning, 62 BSA B40 trials, 89 H*nda Bros 650, 96 Aprilia Moto 6.5, 2000 Aprilia Moto 6.5

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kommando
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Re: My experience wtih the gearbox (quadrant spring)

Post by kommando » Tue Jan 29, 2019 7:20 pm

A lot of that damage looks like corrosion rather than heavy feet, glad you got it sorted.

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madsundaysurvivor
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Re: My experience wtih the gearbox (quadrant spring)

Post by madsundaysurvivor » Wed Jan 30, 2019 10:19 am

Yes, is like a mix of both.
Is like if all began with a small crack in the selector fork spindle (possibility by a big hit), after the wear and corrosion did made the rest..
Surprisingly the gears and dogs are in good condition without marks and without oxide wear

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