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looking for opionons on my build

1421 Views 7 Replies 6 Participants Last post by  Helmut
i got a 400 ex that im in the process of building. i have decided to go with the 426 bore kit. i do alot of hill climbing and looking for the perfect setup. which cam stage would do me best 1 2 or 3? and what would i expect from each? of course im going to get a full pipe and a fan for the oil cooler. which would be better on the carb. jet the stock or go with a 450r?. im confussed on the compression choices i have seen and dont seem to know which is best. i would like to run pump gas like 03 octane but with my build dont know if thats possible. would a bigger cdi box be needed or help?would like the bike to run cooler as when we do ride its hard and long in the mountains and some mud. im also replaceing the timeing chain with the better one cant name it off the top of my head but i know what it is. is there anything else that would improve my proformance that im missing like port and polishing my head? valves? again im open to all suggestions and would like to compare them with other threads i read. i want a good reliable bike withe the power in all ranges with it of course being reliable in the trails. also im been searching for a free downloadable manual for my bike but have had no luck. any suggestions would be greatly appreachated thanks
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POWROLL PRODUCTS FOR THE TRX400EX I read someplace that the stroker +4.0mm was a good way to go.
These guys got a good point. I would go with the 450r carb, aftermarket exhaust, and filter. A huge difference can be made in a quad by moding the the suspension and gearing. You could go with some 450r shocks and drop a tooth on the front sprocket. A smaller front sprocket will make the quad a little slower but you will gain some torque, besides it only costs like 20 bucks so if ya dont like it your not out much $. Everyone says there is no relacement for displacement but I think suspension and gearing are just as important as displacement. Plus you keep the motor reliable.
Almost forgot get a good clutch kit. A aftermarket cdi will give you 1K more rpm thats about it. You can also run a aftermarket fan to keep the motor cool but Iam not to shure how that would work out with the mud on a ex.
Click on the link I posted earlier and scroll down to the bottom. There is a usefull cdi trick/info.
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