Forum

[Charlie]

Hi. Have a look at the 'need advice on an engine rebuild' thread last posted today. It looks like the pre 59 box will not take those wide ratio gears. I'm running a 51 Bullet 350 in long distance trials and the standard box works fine, but I do have a 56 tooth rear sprocket! My engine sprocket is 20 tooth not sure about gearbox sprocket will check tomorrow.
Cheers
Peter

[TonyBax]

Hi Charlie, thanks for the info, sorry I have been away. Plus this site doesn't give you a heads up that you have had a reply to a topic. I'll order the standard sprocket and chain, and see how she rides. Cheers.

[Charlie]

Hi Tony My engine sprocket is 15 tooth. Currently investigating whether it is possible to put the later main shaft and layshaft assemblies into the earlier box? Then I could by our hosts wide ratio gear set and give me a little more mph on the tarmac! Cheers Peter

[vince]

Hi, the later gears will fit, in fact it possible to mix and match provided the two meshed gears are changed. The difference between the early and late is the tooth form. If you are planning to enter competition top gear of 7.5 is about right. 20t engine, 14t gearbox. Vince.

[Charlie]

Thanks Vince that's really good information, what rear sprocket would you use with a 14 tooth gearbox sprocket please?
I'm looking for a donor box but Inot sure how to identify, the concentric gear change and kick start shafts is one id I think do you know any others please? Cheers.

[vince]

Hi, that is using 38t rear sprocket. There were many different internal ratios available at one time. Any heavyweight box will do. Just bear in mind that early Indian boxes are imperial like redditch and later ones are metric. If the box you have is the original with the clutch cable external and the gear change lever up high then that is the type best suited for trials as its narrower. Vince.

[Charlie]

Great thanks Vince. Sorry Tony I feel like I've hijacked your thread, good news though the splendid chap at our hosts explained gearbox identification to me today. Look for the stamping on the upper casing, prefix 'H' is pre 1959 whilst prefix 'A' is 1959 & beyond.

[TonyBax]

Hey Charlie, no problem, all the info is good, cheers, Tony.