916 Pistons in a 748....
 

Has anyone ever put 916bp pistons into a 748 Bp. Can it be done...?

it can be done but you need 916 barrels too, if its done right you'll get something like 853/855cc, John Hackett does a chip too. If you really want it doing well have a chat with Nelly (Cornerspeed) as he's just doing his second 855cc big bore this time on his own 748.

Or try Neil at Sigma Performance. There's probably something about it on his website - I haven't looked - or give him a ring.

If you just stick 916 barrels and pistons on a 748 bottom end you will end up with a comp ratio of abut 4:1 as the piston is too short.

To make it work with 916 cylinders you will need the specific 853 piston which are longer to accomodate the 748 shorter stroke.

As Dukerob says speak to Nelly, he has had his own pistons made up and he also bores out and replates the 748 barrels. Nelly's kit is 855cc.

You can use 916 barrels and pistons but you need to deck the barrels by 2mm and then the bottom end will need balancing due to the pistons being significantly heavier.

Sigma's, and my own solution is to use bespoke pistons that weigh the same as stock so the bottom end is left well alone.

Or simply buy a 916!!!:D:D:D:D

but how many 916's rev to 12000 :devil: :smug:

Ratler

Your being sensible, now stop it!

Allo,

I had my 748 turned into a 853. Neil at Sigma completed the work. The 853 pistons weigh the same as standard 748 ones so no need to re balance the bottom end. My bike still revs to 11500 and makes the same power as a 916. So best of both worlds:roll: Its a hoot to ride too!!!;) Hits 160 no problem. On private roads of course!!

I thought that if the 916 pistons were fitted then the crank cases would have to be opened out??

DC:cool:;)

[Edited on 12-8-2004 by DC]

[Edited on 13-8-2004 by DC]

nelly ,
ive got a 2001 748 and a box in the celler with 916 sp heads barrels and pistons in is it realy that easy? willl it fitt!!! as i was thinking of selling the 748 and buying a 916-996 , this sounds like a better solution to me ............. nat