I did mine myself. I could've sworn also the first check was at 600 mi also. I bought a KLX250R service manual off e-bay and used that as my reference for doing the job. Doing the check is pretty easy. You need to remove the side plastic, shrouds, seat, tank, coil, radiator fan, and the little metal screw bracket on the right hand side of the bike which braces the tank. Also remove the exhaust bypass tubing if you haven't done it already.

After that, the cylinder cap comes right off (3 bolts, very lightly torqued).

Remove the two crank-case plugs - one to turn the crank shaft and the one above it so you can see the TDC mark. Rotate the crank shaft until you see the valves open and close (valve lifter drops down then back up), then about 1/2 turn until the "T" mark lines up in the notch in the top case plug hole.

Using feeler gauges, measure the clearences between the cam shaft lobes and the valve lifter. Inlet valve specs are .1 mm to .2 mm. Exhaust valves are .15 mm to .25mm. There are two inlet valves and two exhaust valves.

Both sets of mine were in spec, though on the low end of the spec. No adjustments required.

When putting it back together, use some silicon gasket sealent on the underside of the cap gasket. Be sure and torque the 3 cylinder cap bolts to 7.8 Nm. Note that this is very light.

If you have to make adjustments, the procedure is a good bit more involved and requires removing the cam shafts, valve lifters, and removing the old shim and replacing it with a new one of a different size. I'm assuming the shims would need to be special ordered, and you don't know what you need before-hand until you get it all apart and can see what shim is installed there to begin with. Then you need to be careful putting the cam shafts back together to make sure they are timed correctly.

But the check is easy - can give you piece of mind. I did mine myself. Took a few hours of work. The second time around would go a lot faster since I'm now familiar with the process.

BTW, the specs came from the KLX250R service manual. I currently have a KLX250S service manual on the way and will confirm that they are or are not the same. If anyone has the KLX250S service manual, can you post the valve clearence specs?

-Brian

 

THe valve clearances are printerd in both the owners manaul and I believe also on the sticker located on the frame of the bike. THe KLX250R, KLX300R and KLX250S should all be the same wince they share the cylinder heads. The KLX300 simply has a thinner cylinder sleeve and a larger piston. Just re-sleeve the cylinder, install the larger piston, reject the carbs, and you have a KLX300S. Oh, the KLX300R might also have heavier engine blanacers to offset the few grams of added piston weight.

 

Nobrakes: Man, you could charge for that kind of post. And the pics from the Valve Noise thread are the icing on the cake! I swear Todd’s last name is Kawasaki. You guys rock! This forum is incredible. Thank you everyone for sharing – you know who you are. I’ve been following this and Adventure Rider and I’m convinced this is the perfect dual sport for my needs. I am getting a KLX250s ASAP.

 

So what is the verdict from all you expert KLX 250s mechanics. Should we or shouldn't we do the Valve check before the listed 7,500 miles specified in the book? I see some that are doing it at 600, and some are just going to wait it out. Maybe at 2,500 miles do the inspections, I have no clue, I'm just throwing numbers out lol

 

i just dont see a piece of metal wearing down at all in 600 miles unless it has 0 oil pressure. Many car manufacturers still have valve checks as maintenance but all beyond 25,000 miles. Jaguar, bmw, mb. High end cars that last a long time so i am assuming our motorcycles to be built to the same or higher calibur. Ill wait till at least 5k miles before i even bother to check. With the air system removed valve noise should be very distinct and easy to hear.

 

Sidenote: Mercedes Benz and Jaguar are have 2 of the worst reliability records i nthe automative industry, MB is the worst by a long way. BMW is only a little below average, a few nothed under Hyundai, and a few ahead of CHevy and Dodge all according to consumers reports. The correct answer was Lexus, Toyota, Acura and Honda.

The valve clearance cahngeing is not so much because of mechainical wear, rather becuase the valve stem can stretch or compress slightly, the valve seat can wear or become better seated against the valve. I do agree that hte intervals are probably fairly conservative, but I think these motors are less tolerate of changes ot valve clearance because of the higher RPM's. The valves open and close very rapidly.

Also, The consturcution and operating conditions of this particular motorcycle engine and a car are very different. For starters that average operating RPM on a motorccyle is 3 or 4 times higher than a car. The specific ouput is typically higher (HP/cc), meaning that hte motor is more "stressed". Most cars have a different valve adjuster set-up as well.

 

I checked mine myself. It's not that bad. Of course, that was when I was sure the manual called for a check at the first service. I wouldn't have done it if I didn't think the service interval called for it.

However, the results of my check are, 1 of the the 4 valves is slightly out of spec on the low side, the other three are borderline on the lower end of the spec, but were in spec. Who knows, maybe my bike was built on the Friday afternoon before a Japanese holiday weekend, but I'm glad I checked them, even if the service check is not yet due. Now I know. I'm also glad the job is not so hard that someone reasonably adept at wrenching can do it. I definitely don't recommend you try this if you don't have the service manual and a torque wrench. You'll also need a set of feeler gauges that measure from below .10 mm to .25mm in at least several steps in between. Other than that, checking the valves is not all that involved and can give you peace of mind if it's bothering you.

 

i have seen multiple mb's with 500k plus miles on them. Jag yes they suck for reliability but still build some extreme power engines.

 

Durability and reliability and build quality are not nessesarily the same thing. Many taxis have over 500k miles, but that doesn't mena that the dirivetrain hasn't had major work done, that the car hasn't broken down or more improtantly that there weren't any manufacturerr defects.

 

I got my bike back from the dealer today. They said 1 exhaust valve was a little tight, all of the others were within spec. It cost me $166. So about 3 hours, plus the cost of the shim. My F4i was around $200, so I'm not complaining. I'll do it myself next time. He claimed he had to remove the exhaust header and some other parts to get to the cam chain tensioner and a second cam chain guide in order to remove the cams. I figure I'm good for another 8000 miles or so depending on the mix of backroads vs. trail use. If i do a lot of trial use and ATV parks, I'll probably shorten the interval. I figure about 200 hours. Although i don't have a hour meter on it.