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[spanner-man]

I am attempting against ever growing odds to rebuild a 1951 model G. The gearbox that came with the bike will not allow the sprockets to line up. the gearbox sprocket and gearbox sprocket are 5/8in. out of line, I strongly suspect that it is the incorrect gearbox? There is a stamping on top of the gearbox which is HAV 793. Can anyone help me with this please.
Contact me by 'phone/txt on 07970819846 or mail at [email protected]
Many thanks, Mac

[Mark M]

HAV is the code for a 1949 500 Twin gearbox if my information is correct but l don't see how it could fit! REgards, Mark

[Tim NZ]

Rear wheel assembly - spacing ? (check wheel alignment too...)


Incorrect gear-box sprocket? Is the sprocket for a #428 or #530 chain?


Incorrect or poorly fitted gear-box bearing?


Gear box sprocket not pulled up fully onto its spline?




Bent frame??




5/8" Out is a lot...

[Tim NZ]

Forgot to add, it may be a J gear-box?

[WDCO42]

Please excuse me for my insertion in this post : Tim, is there a difference of size between the G gear box and the J one ?
Thank's for your answer
Claude

[spanner-man]

Hi Mark, according to Roy Bacons "Royal Enfield-The Post War Models" where on page 56 he says the gearbox was bolted straight to the back of the crankcase? not sure where to go next. any help would be gratefully received. Thank you for your interest. Mac

[Mark M]

A Model G has a separate gearbox in engine plates. Do you have a G or a G2, also known as a 350 Bullet? If so, that could be the problem as the 500 Twin has a longer mainshaft? Over to you! REgards, Mark

[Tim NZ]

WDCO42: Not I am aware of, but then again maybe there is??


Just checking...

[spanner-man]

Hello again Mark.
Yes I am 100% certain I have a Model G Alan Hitchcock can attest to this as I'm sure the money he has had off me for G parts will keep him in luxury !
I would really like to get it finished in time for the Stafford show where its supposed to be making an appearance on our club stand. Only time will tell. If you do happen to hear of a G gearbox I'd love to hear from you !!
Cheers Mac

[WDCO42]

Again, my apologies for my intrusion on this post... Thank's Tim for your answer, hope they aren't different, otherwise I'll be in some serious troubles for the reconstruction of my G/J2...
For Spanner Man,you have a complete G gearbox in the "used parts", heres the thread : http://www.royalenfieldspares.com/Used- ... o/USED2134. This one is interesting, as it seems complete (the clutch adjuster is missing, but you'll find it on the Partbook online). this isn't a bad idea, as I have seen some cracked gearbox cases, between the housings of the mainshaft bearing and the layshaft bush. There isn't a lot of flesh between them...
Hope it will help you.
Claude