Thread: dirt bike rebuild, are there any tell tail signs when its needed?

about 6 months ago i bought a yzf450 for trail rides and general mucking around, i was told it was rebuild by the previous owner and he had put 10 hours on it since then, now i v put about 25-30 hours onto it an i was starting to wonder if there were any tell tail signs that another rebuild is needed. if the previous owner was telling the truth it wont need one for a while now but i dont trust what anyone says unless they have written proof. i do ride it hard sometimes, change oil every 5-8 hours. iv noticed it getting pretty rattly at times but i also know yz's are notorious for being noisy as.

if anyone has any idea that could help me it would be appreciated. cheers

What year? I'd be checking the valve clearances before I went out again

Originally Posted by BRADS

What year? I'd be checking the valve clearances before I went out again

2005

Also when you pour out the old oil from the drain pan, check the bottom of the oil for "stripper glitter"

Originally Posted by BRADS

What year? I'd be checking the valve clearances before I went out again

i also noticed it was rattling from the head, but she starts first time and runs good as gold.... dont they run like a piece shit when the clearances are out?

Originally Posted by 308

Also when you pour out the old oil from the drain pan, check the bottom of the oil for "stripper glitter"

isnt that normal?? haha

Originally Posted by silentscope

i also noticed it was rattling from the head, but she starts first time and runs good as gold.... dont they run like a piece shit when the clearances are out?

Normally only just before they cost you $2500

Originally Posted by BRADS

Normally only just before they cost you $2500

haha thats what im trying to avoid

Originally Posted by silentscope

haha thats what im trying to avoid

Checking the valves is really easy mate and good piece of mind

+1 what @BRADS said. I run a 09 CRF 450 and since I'm in my 50's and don't race it, I expect it to see me out. Keep up with the 5 hour oil changes and 10 hour filters, keep an eye on the coolant, check the valves every 20 or so. If the Yamahaaji runs separate trans oil, change that every 10 too.

Also, replace your suspension link bearings, wheel bearings and swingarm bearings now. I can almost guarantee they've never been done. Reasonably priced kits for all are available from places like Suspension Parts in Albany.

Originally Posted by ishoot10s

+1 what @BRADS said. I run a 09 CRF 450 and since I'm in my 50's and don't race it, I expect it to see me out. Keep up with the 5 hour oil changes and 10 hour filters, keep an eye on the coolant, check the valves every 20 or so. If the Yamahaaji runs separate trans oil, change that every 10 too.

ok cool cheers for the info. im picking it will be fine just with the trail season looming the last thing i want is it to shit itself half way round a track.

What area are you in? I did a few of the MR Motorcycles trail rides around Pukekohe last season, and one over Whangamata. there were some really good trails around Glenn Murray, 35 to 40k main loops.

Yeah some good rides round that area. Miss my dirt bike.

check the valves, easier to adjust than pick them out of the piston

They're pretty bullet proof those engines, especially in comparison to other brands. I wouldn't say they're particularly rattly. Re shim valves and check the cam chain isn't at the end of its adjustment. Try running on 95 or av gas if you're not already and see if that makes a difference.

I put over 200hrs on one of my YZ250Fs and never touched the head on it.

If it's still bad or rattly under power I'd be pulling it down and checking the main bearings, big and little ends. I'm OCD with engine rattles in MX bikes.

Originally Posted by ishoot10s

What area are you in? I did a few of the MR Motorcycles trail rides around Pukekohe last season, and one over Whangamata. there were some really good trails around Glenn Murray, 35 to 40k main loops.

from the wairarapa, theres some good rides around here too, we dont mind travelling to a ride if its going to be a goodey