life expectancy

[jackrb100]

My race bike gets about 35 hours a season. Should I get 2 seasons out off a set off valves running with mild web cam and web cam spring kit also +1 exhausts. Normaly use leaded fuel although some times unleaded. Only had to adjust the valves twice this year setup was brand new at start off year.

[2001400exrida]

you can easily get 2 seasons out of it. I've been riding my 05 for 3 years now with a cam and pipe and k&n air filter.

unless you're trying to keep optimum power for the races....the motor will run a long time with that setup.

most racers just like to get a fresh piston in there eveyr season so that they are getting max power.

[chronicsmoke]

I would freshen the top end every year.

That's what I've been doing and my bike runs like a champ. I can tell it's tired at the end of a season though. I personally wouldn't try and push 2 years, but thats just me. On a trail quad, for sure 2 years or more, a "Race" bike every off season.

Buy your piston, gasket ect now so when you get it rebuilt it wont be as big of a hit on your wallet all one shot.

What piston are you running now?

[Kovatch]

I normally go 60-65 hours on top end rebuilds unless something catastrophic happens. You should be able to get two years given the mild cam and the fact you are maintaining proper clearances.

When you are in the head, you would be able to tell if something is going wrong or went wrong.

[chronicsmoke]

Originally posted by Kovatch
I normally go 60-65 hours on top end rebuilds unless something catastrophic happens. You should be able to get two years given the mild cam and the fact you are maintaining proper clearances.

When you are in the head, you would be able to tell if something is going wrong or went wrong.

I do agree that I could make it 60+ hours on the piston, but my theory is; check the valves/change the piston.

I have my engine builder re-work my engine once anually either way, so the extra 150$ assosiated with a new piston is peanuts imo.

It cost me $200 in labour to P&P my head, grind the valves, install a new piston. and the piston was 150. so for $350 anually, (probably less since a P&P was also included) you will have a fresh top end.

That's my take on it anyway..

**Edit: I should have also added that my bike only runs when I'm at the track. I dont trail whatsoever, so amount of time on my top end is only high RPM 'abuse'.

[jackrb100]

I run with a 14:1 piston but the piston gets changed anyway regardless. Its just the valves I am wondering about. And this bike also only gets run in races. Thanks

[Balaz_73*00]

My head will have 2 full seasons on it after this season. I build it fresh initailly and have had no problems. I was planning on fully rebuilding it though after this season just to be safe. valves, guides, seats, ect. I race and ride the piss outa my bike but do keep up on all maintenance.

[turkeyracer]

Originally posted by Kovatch
I normally go 60-65 hours on top end rebuilds unless something catastrophic happens. You should be able to get two years given the mild cam and the fact you are maintaining proper clearances.

When you are in the head, you would be able to tell if something is going wrong or went wrong.

I used to get 5 hours out of my fully buit raptor 250 :eek:

[Jason Hall]

What kind of valve's are you using?? That Is what Is needed to know IMO. If you have titanium valves, and have adjusted them 2 time's I would change them For Sure! If stainless, then you might get away with running them another year. Once titanium valve's start to wear, they don't last long at All. I adjusted the valve's In my 06 (Factory titanium) twice, and they were Done. After the first adjustment, they wore out within a few hours time.

[quad2xtreme]

Originally posted by Jason Hall
[BOnce titanium valve's start to wear, they don't last long at All. I adjusted the valve's In my 06 (Factory titanium) twice, and they were Done. After the first adjustment, they wore out within a few hours time. [/B]

X2. I went 3 years before having to adjust mine. Once I did though, they only lasted a few more rides. I had to have the head completely redone.