The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => Gearbox, Clutch, Primary => Topic started by: Black Sheep on 06.12. 2018 16:39

Title: Plunger gearbox attachment
Post by: Black Sheep on 06.12. 2018 16:39

Has anyone any idea why the plunger gearbox is attached by 2 bolts and 2 studs? I found I had to remove the studs as well as the bolts to separate the gearbox - all part of the replacing the gearbox sprocket saga. I'm contemplating replacing the studs with bolts so that next time I (or realistically someone else in 35,000 miles time) can manage it without having to remove the mag to get at the studs.

Title: Re: Plunger gearbox attachment
Post by: Greybeard on 06.12. 2018 16:43

I also wondered about that. If you don't want to remove the mag, you need to get those studs out! I guess the shank of the studs creates a more accurate register for the box.

Title: Re: Plunger gearbox attachment
Post by: AdrianJ on 06.12. 2018 17:59

I thought it was supposed to be 4 studs, at least that’s  what mine had☹️.
I’ve just replaced my studs with bolts. Don’t know if there will be any ill efffects.
Even with the engine out of the frame I couldn’t get the gearbox off or on again without removing them.
Adrian

Title: Re: Plunger gearbox attachment
Post by: Greybeard on 06.12. 2018 18:20

Quote from: AdrianJ on 06.12. 2018 17:59

Even with the engine out of the frame I couldn’t get the gearbox off or on again without removing them.
Adrian

I think you can without the mag in the way.

Title: Re: Plunger gearbox attachment
Post by: muskrat on 06.12. 2018 18:51

G'day fellas.
Yes a real PITA job. I replaced the studs with bolts as well.
With the amount of work to change the sprocket I factor in a full motor rebuild as well.  *pull hair out*
Cheers

Title: Re: Plunger gearbox attachment
Post by: Black Sheep on 06.12. 2018 22:20

4 bolts it will be in that case. The parts diagram (see Draganfly website) shows 2 studs, 2 bolts. I was annoyed at having to remove the mag to get the studs out as I had just replaced it and timed it up. Ho hum. Sitting nearby is the Velocette looking smug. To remove gearbox sprocket: Remove pressed steel cover (2 nuts), remove gearbox sprocket (1 nut).
Not going for the full engine rebuild. It was going beautifully before this (as it has been doing for years and years) and I want it back on the road. It's my most useful, reliable, all purpose bike. 

Title: Re: Plunger gearbox attachment
Post by: Greybeard on 06.12. 2018 22:53

I have been removing and replacing those studs by locking two nuts together. Last time, I had the mag off and discovered how simple the job is without it in the way.