KTM RFS Valve Adjustment on YouTube transcript of instructions
Courtesty of McGoodies.com
This is a KTM RFS 450. Today we're going to be learning how to do a valve adjustment the quick and easy way. The first things we're going to do is remove the seat, the tank; we're going to loosen the radiators and remove the radiator braces. There's a couple of years that this procedure won't work exactly the same way, that's the ' 03 450 and the '03 plus 525 SX's.
OK these are the tools you'll need to do this project: [ flat screwdriver, 8mm wrench, 10mm wrench, new valve cover gaskets ]
Let's get the seat and tank off, then you're going to want to remove radiator braces, loosen the radiator mounts, remove covers-screws, So, we'll go through that real quick, For easier access you're going to remove this one tank mount... You're going to remove your radiator cover and this pertains to both sides, not just one. Loosen the radiator bolt brackets; make sure you put it where you can find everything when you're done. Once we're done we have the radiators loose; what we're gonna do now is clear a few things out of the road to make it easier to work on the bike : your two quick disconnects for your stator, you're gonna pop those apart, just to get them out of the way - we just want to clearance this area up to make it easier to get in to the back valve cover - easiest way to do this is to get a ratchet wrench, that way you can get up under everything, speed through it and not having to be fignthing a one-turn wrench at a time - so we just buzz through here... Now if you do this according to the KTM manual, you need to drain the radiators and remove them, but there's really no reason to, with a long screw driver and a feeler gauge, you can get right in there.
One thing that's really nice to do, is if you have an hour meter, that way you can track the exact hours you have on the motor, that's run hours, then you'll know exactly how long you've been running between valve adjustments, otherwise it's all just a guess. As you can see here, we've installed an hour meter, in the air box of this bike. The hour meter picks up on a lead that you drill a little hole through the front of the air box small enough for the wire through the air box so that it seals, then you can see where you take the wire up and you can wrap it around the ignition coil and all that does is it senses the electrical field and causes the counter to run, so the counter is actual hours of run time, it's not how long you've been out on the trail; you'll find there's a big difference between how many hours you've been out on the trail versus how many hours is actually on your motor.
Now to set your Top Dead Center, usually you have to do from the front here, there's a lock down bolt for the crank. You have to figure out if you're 180 degrees off Top Dead Center. The way we adjust the valves here, we don't need to do that so that's a few less steps that we have to do, what we Do do : Put the bike in high gear, rotate the wheel forward - using the compression release makes it easier to rotate forward ... and what you're going to do is rotate the wheel forward until you see one of the rocker arms move, either the intake or the exhaust - it doesn't matter. So if you look down, see our intakes are moving... Now if you go past that, you're at Top Dead Center, but you're 180 out, your valves are in the overlap stroke of the cam and as you can see if I move the wheel at all, both intakes and exhaust both move at the same time one is opening and one is closing; that's the wrong Top Dead Center; what you want to do is to roll past it ... when you're 180 off of Top Dead Center, you will be caught in the overlap of the cam lobes, in the intakes and exhausts and as you can see when I move the wheel, the intakes and exhausts both move at the same time, if you adjust at this point you'll be about 40-thousandths off on your valve adjustment, you don't want to do that, it gets noisy not having them properly adjusted so what you do is just like that, you roll past where the overlap is on the cam and if you continue rolling you can see now we are only moving the intake valves, you roll backwards and you'll see there's a time-delay moving the intakes and exhaust, so what we're going to do, we're going to leave it in the backward position to where the exhausts are making contact with the lifted cam lobe. Then what we do, we know that the intakes are completely closed, so now we go and check our valves. Use a feeler gauge - Five Thousandths KTM recommended spec, you slip it under the tappet and here his adjustment is just right ... there's no need to adjust this one valve - if it'll slip under nice and snug - you don't want to force it, you don't want to bend it, just nice and snug; then you'll know that you're good. Now let's check the other side, it's doing the same thing...This is a little loose, probably about a thousandths loose, you we're going to go ahead and tighten it up just a hair. To do that you need a 10mm wrench and a flat blade screw driver ... you loosen your locking nut on the tappet, now using a light finger pressure, you will just very lightly, I'm just using 2 fingers, I'm not really wrenching on the screwdriver, just down to where it snugs up, then what you're going to do, you're going to hold it in place and tighten the locking nut back down.
Now I'm going to show you another trick real quick. This is you're out in the field and you feel you need to do a valve adjustment, you can do it without a feeler gauge. It's called the 6-turn Method. And what you do, the pitch of the threads mathematically comes out to a sixth of a turn is 5-thousandths of an inch. You notice that your locking nut has 6 points on it. So you take your screwdriver and you aim and go ahead and tighten it all the way down ( oops slipped there ). Line up with one of the points of the nut. Now what you're gonna do, you're just gonna turn the tip of the screwdriver to the next point on the nut and that's gonna be a sixth of a turn. So we're gonna go from here ,,, to here. Then you lock it down holding the adjuster screw in place. Now it's about 10 foot pounds to hold those in place, so you don't want to wrench on them very hard. Now here's our 5-thousandths - slips right in perfect fit, we didn't even have to measure.
The fronts are a little harder, the exhausts are a little harder because you gotta work around the radiators, but not that much of a difference. Now what we're gonna do is go ahead and rotate the wheel until our intakes move. See here our intakes are moving and our exhausts are not. So you roll right up to it, that's the start of the intake stroke ... that's actually the Finish of the intake stroke. So now we're going to do the exhaust. To do this, get your radiator out of the way, push your wheel out of the way, and then come in from the side just like this. Make your adjustment ... we're spot on right here and you're adjustment will the same on your exhaust, it's 5-thousandths of an inch or a sixth of a turn whichever works. So that intake is fine. Now we're just going to move everything out of the way, rotate this radiator out of the way, and do the same thing. And that intake is perfect, er, that Exhaust is perfect. That's pretty much it in a nutshell for doing your valve adjustments without worrying about Top Dead Center or worrying about locking anything down.
What we're gonna do now is put new gaskets on the covers and button everything back up. One thing you do want to do is that I do recommend you doing is that you track your adjustments especially if you have an hour meter. Go 20 hours as KTM recommended, write down if they moved at all. This way you have a running total of how much your valves have moved. Once you get to about 10-thousandths adjustment, you know your valves are starting to cup, and it's time to consider a rebuild. Until then, keep adjusting, keep counting and ride all day.
Recap of Valve Adjustment Tools
1. 8mm socket
2. 8mm box end wrench
3. 10mm box end wrench
4. .005" feeler gauge
5. flat blade screw driver
6. valve cover gaskets
To order any special tools or parts go to :
2084 Foothill Blvd.
Pasadena, CA 91107
or call 1-888-252-2000 and ask for Tim or Travis