CMSMJ1 wrote:Hi all,

These are the maximum allowed overbore for racing.

Have you checked with the other clubs? most clubs allow manufactures maximum over size but Bemsee changed there rules to allow everyone 1mm oversize to level the playing field as Honda don't do oversize Kawasaki's only go upto 0.5mm and the Yams go upto 1mm

You can use 1mm over at the manx now too I believe

I only checked Bemsee,and the Manx,thats what I was thinking of doing.The engine I bought as 1mm over was raced in New Era and thundersports. Think it would be a good idea to check though.

You can run upto 450cc in Thundersport GB Junior powerbikes not sure about new era though.

Better look into that then! It was sam Hornseys engine.

Hi guys

just seen your post - I need 4 pistons for a very poorly NC29 (CBR400 RR). The best price I got so far was £575 so would be very keen on joining the group buy. I will also email Sarah.

Thanks

I'm also interesting for set of overbore kit. So, if the price will be 75GBP for piston I'm with..

One more - could I order more than +1mm pistons for the group price?

I'm also curious from the V4 guys, what a max *safe* overbore would be.

I don't have racing displacement requirements to deal with, and would like to use stock rods (cryo treated), but will balance everything.... so for an NC-30 what could I run, +2mm, +3mm ?

if you can get them to £75 a piston thats good, i may even put off reringing the standards as last time i bought some rings from honda it was around £100

pencil me in but cant say for certain, unless i have 12 volunteers for sticker kits?

Rick Oliver was telling me the other night what they will bore to.Give him a shout.We are having a 57mm set as well as the 56.They can do standard if your club wont allow 1mm over.

Excuse my stupidity if ive missed something but what CC are you gunna end up with with these pistons? and whats the likely power increase?