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[Ginetta lad]

I now have my 5 speed conversion working on a 4 speed back wheel and want to replace the chain and sprockets soon. I know the gearbox sprockets fit differently but are there differences in the chains that I can use too? I bought a new O ring chain from india only to find its too short by a link to fit around my current 17T gbox sprocket. The new chain I bought measures as 5/8 X 3/8 which seems to be a 530 chain? Maybe the Indians run lower gearing?
My 4 speed box had a 19T sprocket so as my bike is tuned I was thinking of fitting an 18T or 19T front sprocket anyway. My back sprocket is a 4 vane 38T standard hub but does that have a different pitch to a 5 speed front sprocket? Can I just buy a standard rear hub and new 5 speed front sprocket and get a chain to fit both ok? If so what spec and length of chain would I need for an 18 or 19 Tooth sprocket?

Thanks in advance.

[mauri]

[Alan R]

Hi Guys------- I believe I'm correct in saying that the Bullet '65 was either the first OR was amongst the first of the "Classic" Iron Barrel bikes to have a 5-speed box fitted as OE......It's rear wheel was the standard "Classic--4 speed" so there I would say was your answer ie}--- Checkout the factory spec.of a Bullet'65.................. As MAURI points out if you want a detachable rear sprocket then you'll need a new, machined hub to take the new sprockets..

[binary]

When I put my 5 speed gearbox onto my 350 iron barrel bullet I just put a new 16 tooth sprocket on the gearbox shaft. The rear wheel sprocket was like new and so I just used a new 4 speed rear chain and it works perfectly for me. If your chain is too short by a link then you can put a chain joiner link in and it will be the right length. My new chain came with a joiner link. I am running a 16 tooth sprocket as my bullet is in standard trim. The rear chain that I am using is an O ring chain as well. The joiner has extra O rings for it to put on when fitting the joiner.

[Ginetta lad]

So I was right on the size of chain which are 5/8 x 3/8 and think I need an offset link to extend the new chain I have. My gbox sprocket is an 18T not a 17T so my gearing will be one tooth lower than before the conversion. Now how are the rear sprockets machined? Are the teeth just turned down to fit on the detachable rings?

[mauri]

yes, you need only to turn down the teeth of the original drum/sprocket.

drill and tap 8 M5 and that for a way cheaper price than the 71,50 + vat and shipping.

this is how i do it every time.

be aware that its cast iron, so its a bit harder to work on.


you'll need the sprocket to get the spacing right.

use a dab of medium locktide when mounting the sprocket to the drum.

and as its an M5 dont pull on it hard, 10NM is enough.

[Alan R]

Yes, and don't forget that the drum you're turning and drilling is of Indian make so do be on the look-out for the occasional Chilled-Spot.....