Problem and a question 450r 04

[circa411vm]

First of all, sorry for my english. i live in canada and im french so ^^.

I got a 450r 04 with HRC KIT, HCII and DG exhaust i got idling and starting probleme. When the quad is warm it starts easily from the second or third kick but when its cold it take a LOt of times to start it. (almost 10 min !!)

Edit: Also, i cant let te bike idle when hes cold. i have to always press on the throttle

Also, when my quad is warm he runs ok but when hes cold it run at a high rpm. (its not because my choke is on). I tried to fix it with the A/F on the carburator but when i fix it when hes cold i have idling problem when its warm.


Question: Im actually rebuilding it and i dont know what piston i should use.

You can also recommend me some mods that would help me fix those problems.

[trx400 rider]

check your valve gaps it could make it hard to start

[miles Machine]

well you have a couple things going on there starting good when cold and not when hot sounds like a faulty choke....or your in a need for a vlave / decompressor adjustment.

when it starts you have to idle it high or it will die...sounds like a clogged jet...but dosnt make sense why its fine when hot

id honestly take the carb apart check and clean all parts very good...and also do a valve adj.




CP pistons all the way

[Ruf Racing]

Check your valves.

[circa411vm]

Thank you guys. I m gonna do it when im done rebuilding it

[wckedclownz69]

2nd the cp piston and i have an 05 and had the same problem.. intake valves got too tight.. but if your doing a rebuild then you will have to adjust them anyways... and mines a she lol