2005 Honda TRX 450R Rebuild Top End

[2 fast 4 u]

So i recently bought a Honda TRX 450r 05 kick start model i am the 3rd owner. this bike ripped when it was running but i ceased it.I freed up the piston but there is little compression now. i think i ran it out of oil but it was like 20hrs or so since the last oil change. My real question is that i heard you have to rebuild the top end every 15 hours is this true? Now i have bought a new big bore kit to replace the cylinder and the piston but i dont really want to have to rebuild it every 15hrs.

[2 fast 4 u]

i have a full Yoshimura exhaust

Dyno Jet kit

K/N air filter with sleeve

Hot camshaft 

cylinder works 479cc big bore kit (Getting put in within this week)

Edited October 18, 2016 by 2 fast 4 u

[Ajmboy]

Moved to Honda Forum, edited title for better responses/searches.

[Shane Pillar]

I read that you should rebuild it every 50 hours of operating. I have a 08 raptor 250 that we are rebuilding for cross country racing.

Are you rebuilding this for racing, or because it's shot?

[Shane Pillar]

We are putting in a hot camshaft, chrome valves, and new piston rings. Maybe a high compression piston but definitely new rings.

I have a powercore 4 slip on by fmf and will soon be getting a power bomb header.

[quadnut20]

On ‎10‎/‎18‎/‎2016 at 5:08 PM, 2 fast 4 u said:

So i recently bought a Honda TRX 450r 05 kick start model i am the 3rd owner. this bike ripped when it was running but i ceased it.I freed up the piston but there is little compression now. i think i ran it out of oil but it was like 20hrs or so since the last oil change. My real question is that i heard you have to rebuild the top end every 15 hours is this true? Now i have bought a new big bore kit to replace the cylinder and the piston but i dont really want to have to rebuild it every 15hrs.

Ive owned my 05 450R since new !! Ive only had to rebuild the top end 2 times ! the trick is to keep the valves adjusted and do regular maintance

[quadmaniac]

I agree with quadnut20, regular maintenance is the key.