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B40 Gearbox Probs

Featured Replies

Hi Guys

Bsa B40 with wd ratios

Sometimes will ,but mostly not select 4th

Then will not select 3rd

Gearchange is a bit wooly

New plungers on the gearshaft new bearings etc

Tried differnt quadrants

Anyone no where to look next?

Marty D

I had a similar problem once with a B25 g/box. I had somehow assembled the box such that the output shaft was shimmed too far towards the clutch and I could only engage gears 1,2, and 3. Check the primary chain alignment i.e. clutch teeth aligned with the engine sprocket, if the clutch is too far out then this may be the problem, otherwise hopefully someone else has a better suggestion, good luck.

  • Author

Had a look the clutch dosent appeared to have moved out of line

Is the gear tight to the output shaft/clutch 1st or 4th?

Going to have to let a Proper Bsa mecanick tinker

Marty D

,

If you go to www.classicmotorcycles.org.uk will find some useful technical information and there is blown up dwg of the gearbox cluster that maybe helpful.

  • Author

Thanks will take a good look and see if i can find iut whats going on

Saying that i see that the input shaft(clutch) has a considerable float

When levered the shaft will move back and forward

Marty D

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