I bought one of the wiseco 89 mm 440 kits and I am dissapoited with its performance, I can feel a little more torque but when i raced my friends stock 400ex i took him at first but he caught right back up with me, He is about 50lbs faster but I have raced him before and did not do much worse. I have a stock exhaust and stock cam. Only other mods are 6 degree advance key. Jet kit, and white power filter. Im guessing im not getting enough flow threw the motor. What would be the next step.

 

To do it all proper with the 440 you need cam, pipe, porting, and bigger valves. You won't feel hardly any difference if you don't put those in. Your engine now is like a coark in a bottle, you need to get a pipe and re-jet that would really open it up. If you have extra money get a cam and have some porting done. That 440 has potential if set up correct. For starters I'd get a pipe, a White Bros E-series Pro Meg seems to win every pipe shootout for the 400ex I've seen.

 

..Hello..If you dont want to spend a hole lot,just put a pipe WB is good but i think the Sparks x6 is better,but your going to pay for it.And also again if you dont want to spend a lot,just put in a drop in cam.Also most 440 kits dont have 11.1 like they say they do.You need to deck the cyclinder for max com...heres a few links that should help you with this http://www.exriders.com/vbb/showthre...5&pagenumber=1 and http://www.exriders.com/vbb/showthre...5&pagenumber=1 Iv been told a 440 alone is only worth 3 hp.I had a 440kit with slip on,HRC cam and just a clean up port job,with stock carb and id take more raptors off the line and stay there untell 5th gear...So yes it'll run good,just need to work her a little more...Hope this Helps

 

You Propely need a high-pormance pipe and silencer, high-quality air filter (UNI or K&N), Jetting, tires (for better traction),a good cam (powroll, web cam, ect.) Or Powroll has there 400Ex kits at this link= http://www.powroll.com/honda_trx_400ex.htm

 

That degree key won't help you with having hi compression

 

I have heard the degree keys aren't that good either. It takes more than just 43cc and a high compression piston to get the most out of a 440 kit just like the other guys said. If you look at most of the full blown engine kits from any of the online race shops they include:

440 kit
Carb
full pipe
cam
head work
and some add
hard faced rockers
heavy duty valve springs
Clutch basket

I'm thinking about shipping my motor to Hetrick next year and getting the whole 9 yards done.

 

Thanks for all the information, thats kinda of what i figured whas wrong. Im planning on getting a white brothers sliip on. Im in college and dont' have that much extra money. I have a friend that works at a muffler shop. Do you think the wb universal silencer would have all ill effects. Also i plan on getting hotcams. I like to ride the woods, sand, drag race, just about everything. I really don't want to loose to much bottom end and would like to gain as much as possible without removing the rev limiter. Im not sure whether or not to got stage 1 or 2.

 

Ct Makes an awesome pipe also might want to check them out I have one and would not change it for anything just my .02

 

I agree that CT makes one of the best pipes for the 400ex, I have beat many white bros pipes at silver lake(one guy I couldn't beat, and his 400 was yellow which made the defeat worse)

 

CURTIS SPARKS PIPE (X-6) OR WHITE BROS. E SERIES IS WHAT YOU NEED. WHY DID YOU FIRST GO WITH A BIGGER PISTON RATHER THAN GOING WITH AN AFTER MARKET PIPE?[img]i/expressions/face-icon-small-confused.gif[/img]