Gear Shifter Stuck

a few weeks ago i purchased an 03 yz450f. i got it for what i thought was a steal. The guy said he thought it needed a head gasket because there was water in the oil(milky) I offered him $1800 for it and we had a deal. i brought it home, decided to kick it to see if it would kick thru a stroke and the thing fired right up. of course i shut it off immediately knowing the oil was bad. I did some research on forums mostly on ThumperTalk and decided i should replace the waterpump seal and bearing and if needed the shaft(which by the way looked perfect so i didnt replace it). I dissasembled the engine, i didnt split the cases but i pulled out the clutch pack to see if it was worn because as i put the bike in gear when i was running, the clutch was not fully engaging, it was creeping forward. After taking head and cylinder off, it appeared the piston and rod and valves were almost new, harldy any carbon buildup and the cylinder was smooth as glass. i poured about 5 or 6 quarts of oil thru the engine and drained as much of the white oil out as possible and replaced the water pump bearing and seals. after spening quite some time(im new to four strokes) getting the cylinder, head and cams back in and the timing correct, i put everything back to together, checked to insure the valve clearance was in spec(all 5 were) and kicked on it for almost 20 minutes. all i got was back firing, i could smell gas and i checked the plug to see if it was firing and it was but i replaced it anyway. it still didnt crank. i didnt do anything to the carb while it was off, so i dont see how that could be the culprit. i decided to give it a break until the next day so i leaned it up against my weight bench while it was in neutral and it apparently put to much pressure on the shifter because it is in gear now and i cannot get it to go into neutral or any other gear. also when i pull in the clutch it doesnt seem to engage. it is the same as if the clutch were not pulled in. I was hoping someone would have some input into the not cranking and the locked up shifter. I have a feeling that the cams may be off a tooth and it is difficult to decipher where the I is to make sure it is at tdc. also i was wondering if the the clutch could be the culrpit for the shifting problem. I believe it could be the shifting fork, i hope not, i dont want to split the case. Anyone had any similiar probs?

You have a lot of different problems all at one time for somebody from Virginia, don't you?

First, the term for what the clutch isn't doing is "disengaging". You disengage the clutch by pulling the lever. Check your free travel to start with. We'll come back to that in a minute.

If you aren't sure where the TDC mark is, or if you're suspicious that it could be wrong because of a sheared flywheel key, pull the plug and feel where TDC is with a thin screwdriver. There are three vertical lines scribed on the flywheel. Two are at 11:58 and 11:59 on an imaginary clock face, and are joined by a horizontal scribe mark so they vaguely resemble an 'H'. These are for the ignition timing. The third is at 12:00, and that's TDC. Double check the timing one more time.

It may be that you just need to crack the throttle open slightly when cold starting instead of adhering rigidly to the "don't touch the throttle" rule. Mine likes that. Just barely above idle, no more.

You should be able to shift the bike by rocking the wheel hand on the stand, or by rocking it back and forth on the ground, holding pressure on the shifter until the gears change. The lever should re-center freely. If it does that, there's no problem with that assembly (and you can't hurt it by leaning it on a bench).

A clutch that drags excessively will gum up shifting by failing to release the load on the selected gear so it can be disengaged. Then, if it does come out of low, you'll have so much force on the shifter that you can't stop at neutral.

Besides free play adjustments, things that will cause the clutch to drag are:

> Weak, uneven length springs

> Warped plates

> Notched clutch basket

> Water damaged friction plates. This is rare, of course, because water in the oil is rare. But the friction plates don't like water at all, and they will frequently swell and flake apart and generally throw a tantrum about being exposed to it. Something you should look into if you can't fix it another way.

I pulled the entire right side off, including the clutch and the case as well. I found where the "fork" that shifts the gears had slid off so i put it back on. that fixed the gearing problem, i reasembled the engine, filled with water and oil again and kicked it 25 or 30 times. i blipped the throttle a couple times and all it did was backfire. while in gear, the bike still will not roll at all. i pulled the clutch basket and inspected it as well as the plates and measured them according to the manual and they are well within spec. i am at a loss as to why the clutch refuses to work but moreso why the bike will not fire up. i am getting spark and fuel as well. i plan to check the timing as well as the valve clearance again as well.

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