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View Full Version : jetting changes for xr400 cam



shook
12-04-2001, 06:25 PM
I put the xr400 cam in it defiately feels stronger now I was wondering what jet changes need to be done.I am running a 42 pilot raised the needle one notch from stock and am running a 170 main right now I live in Midlothian Va. its right at sea level.Do these jets sound safe to be running it for now to fine tune the jetting or do I need to go bigger.It definately runs a hell of alot better than before and iI havent noticed any low end loss just a whole lot more mid and a pretty strong topend.Oh I ported the head a little not much just cleaned tyhe bowls up and did cut away some of the exhaust it is definately restricted but there were not a lot of casting marks or should I say they were not really bad at all.I only wished I would have ran the xr400 stock head gasket instead of the cometic head gasket Ive heard it will raise the compression a little but oh well.

12-04-2001, 07:52 PM
Try the jetting that your already running, sounds pretty close to me.

patrick delao
12-05-2001, 07:50 AM
cometic sells 2 type of gaskets I just ordered there high performance gasket for my 440 and it is .025 thinner then there other gaskets and they said it was thinner then honda's xr and ex head gaskets.