DirtRider . Net MX, SX, Arena Cross, Off-Road Community
Dirt Rider . Net Text Version Home
Dirt Bike Dirt Bike Dirt Bike Dirt Bike

This is the text version of DirtRider.Net
Click Here for the Full Version


Pages: 1

Hour Meter / YZ250F Service Intervals

(Click here to view the original thread with full colors/images)

Posted by: promax150---------------------

I have a 06 coming. First 4/stroke and first bike with an hour meter. So given this tool what would you recommend for service intervals. Oil change, Valve Clearance check, Piston Replacement, etc.

In two stroke land I would count rides and seasons. Trans oil change after every 4 rides, piston every year, etc.

Thanks in advance.


Posted by: Sawblade---------------------

You can get a hour meter at Sears for about 30 bucks. Once you have taken delivery of your new YZF take time to read the owners manual as the manufacture will have service intervals listed for oil changes, valve checks, and piston engine parts replacement. Use this as a guide. For my RMZ 450, Suzuki recommends changing the oil every 6 hours. I change it every 3 - 4 hours as it makes me feel better.

Enjoy the new bike!


Posted by: Buckholz---------------------

piston, rings, cam chain, valves, valve springs every 30 hours


Posted by: J.B.426---------------------

A little late on this but....
Piston, rings, cam chain, valves, valve springs every 30 hours would be way over doing it unless you're a national level pro.

I would change the oil every 3 - 5 hours, check the valve clearance after break in and then about every 15-20 hours after that. You'll probably find they are fine and everything else should go much longer than 30 hours. I think even 125 2 stroke piston lasts longer than 30 hours


Posted by: Rich Rohrich---------------------

Quote:
Originally Posted by J.B.426
I think even 125 2 stroke piston lasts longer than 30 hours


They don't but that doesn't stop people from leaving them in that long.

At a minimum you have to change the cam chain EVERY SEASON on a YZF250. The valves and springs will give you warning about when they are wearing out. If you drop 5% off the initial valve clearance your valves are worn out, if the clearance changes more than 10% (usually about .15mm) the valves are in danger of breaking the heads off from wear and need to be replaced ASAP.

If you are racing regularly , then changing the piston, rings, valve springs and cam chain every season at a minimum is a wise move. The Yamaha YZF is hands down the most reliable four-stroke on the market. The problem is, because they tend to be very reliable people confuse this with them not needing ANY maintenance. YZ250Fs tend to be really vindictive if you ignore service intervals for too long.


Posted by: BadgerMan---------------------

Quote:
Originally Posted by J.B.426
A little late on this but....
Piston, rings, cam chain, valves, valve springs every 30 hours would be way over doing it unless you're a national level pro.


Don't push your luck as a YZ250F is not an XR. Thirty hours is about right for a cam chain regardless how you ride and much less if your riding hard. You might consider swapping the chain out each time you check valve clearance as it's only a twenty dollar item. The potential cost of not replacing it is huge. I ride mine in the woods only (couple rides/month) so a piston every other season has been a good interval for me. IMO, the valve train is more critical than the piston/rings as far as preventive maintenance. Keep a close eye on it.

I replaced the crank and bearings after three seasons, mainly due to potential failures related to CS dimensional issues during the first year of production. There was no indication of wear or that a failure was imminent. Just cheap insurance.

All that said, I am still running original valves in my 2001. I plan to pull the head off next month and send it off for a set of Kibblewhites though.


Posted by: J.B.426---------------------

Good points. I wasn't aware of the cam chains needing to be replaced that often, but I don't have 250F so I haven't checked into that. I'm in no way advocating treating a YZ250F like an XR and I think that there are probably too many people who buy a modern race 4 stroke under the assumption that it will require less maintenance than the old 2 stroke. Of course that's not the case, they just require "different" maintenance, be that good or bad.

I think we can all agree that 30 hours, in most cases, is a little too pro-active in regards to pistons, rings, and almost certainly valves and valve springs as well.

This may all be moot for me though, as I contemplate going back to the stone age with a 250 2 stroke.


Posted by: BadgerMan---------------------

Quote:
Originally Posted by J.B.426
This may all be moot for me though, as I contemplate going back to the stone age with a 250 2 stroke.


Don't tell anyone but I am doing the same........

The cam chain is real light and stretches quickly. Luckily they are cheap and easy to replace.


Posted by: zcookie49---------------------

I too have the original valves in my '01 250f, actually, everything is original except for a piston change last year (didnt ride at all in 02 due to injury). Dont flame me on this, but last year when I changed my piston was the first time that I actually checked my valve clearence, and they were in spec.
I ordered a valve clearence measuring tool, I need to check them soon.
I dont ride the big bike as much as I used to in 01 & 03, since I split time with the Fiffty...... I do keep up with the oil changes frequently and air filter cleanings.
I am lucky (knock on wood) that nothing has happend as of yet. I should probably order the chain, valves and springs though. My top end still feels pretty fresh though.
.... I dont race the bike. I would follow the suggestions these guys give though, very knowledgeable.



Text Version Home





vBulletin Copyright ©2000 - 2009, Jelsoft Enterprises Limited.
vB Easy Archive Final ©2000 - 2009 - Created by Stefan "Xenon" Kaeser