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1978 PE250 Ported... now jetting

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I have a 1978 PE250. It ran good in stock form, but you had to slip the clutch out of a corner or obstable to get any power or lift the wheel. So, I bought an old RM250 manual with porting specs and found some 70's ISDE PE250's race team porting specs and ported my first cylinder, added a RM head, RM pipe and a FMF turbine core II silencer. It honks! Its Fast! The stock jetting was a 40 pilot and a 260 main. I started jetting with a 45 pilot and a 270 main and it ran good. I ended up with a 50 pilot and a 330 main and it runs clean all the way through the RPM range. This seems like a big jump to me. I use the bike for vintage EVO hare scrambles and I just want it to be right. Any thoughts would be greatly appreciated. Thanks!

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That was a pretty big jump and that seems like a huge main jet compared to stock, but you don't have a stock bike anymore. Porting and the other add ons can really effect jetting and not always how you think it would. I remember a shop owner telling me about how a ported and piped banshee or blaster I can't remember actually used a smaller jet then stock. There are so many variables when it comes to jetting a bike, as far as temp, humidity, altitude, etc. in addition to whatever mods you have done to your bike. I highly doubt there are many people running a similar setup as you and even if they are, unless they live in the same area, their jetting will probably be different. If your bike runs good and makes good power I wouldn't give a second thought to how other people have their bike jetted.

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yeah not that i'm complaining I just was trying to find where to fat was until I ran out of jets here in steamy fla, sea level,80 degrees. thanks for the thoughts and reply.

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