440 problems

[Got_Mort03]

i have a 2003 400ex with the wiseco 440 kit stage 1 hotcam, port and polish, with a full yoshi exhaust....it seems like i just keep pouring money into this thing after i got it installed i bent 2 valves, and i have had to replace the rings twice in the past 2 years.....i am thinking of selling it and getting a new trx450r but i dont know how a new 450 would compare to what i have now if there would be much difference at all...i am just frustrated of woking on mine all the time. any opinions would be great.

[yfz450admirer]

I was at the same point with my 440 4 months ago. I ended up selling the 440 for 3250 and buying an 05 450r. I like the ergonomics of the 440 more and it has more power than my stock 450. It is frustrating to have a machine that is not working, however if I had it to do over again I would have kept the 440 and worked out the kinks in it. I am actually trying to sell the 450 now.

[400exrider707]

Originally posted by Got_Mort03
i have a 2003 400ex with the wiseco 440 kit stage 1 hotcam, port and polish, with a full yoshi exhaust....it seems like i just keep pouring money into this thing after i got it installed i bent 2 valves, and i have had to replace the rings twice in the past 2 years.....i am thinking of selling it and getting a new trx450r but i dont know how a new 450 would compare to what i have now if there would be much difference at all...i am just frustrated of woking on mine all the time. any opinions would be great.

2 sets of rings in two years? Serious racers replace theirs every few motos! 2 sets is not that much over that period of time. It's called maintanence, your going to have to do it with any quad. As far as bent valves, it sounds like whoever put it together didn't time it right or put a crappy stretched timing chain back in when they built it.