HUGE mistake adjusting valves, pls comment

[johnsls]

I adjusted my valves last week, then started it up and it sounded worse than b4 I adjusted them.. but I thought it was just me.

I didn't ride it I just hit the throttle a couple times then shut her down.

So a day or two later,,, I'm reading on here and a light goes on..."Hey genious you didn't take it to TDC" (top dead center)

So I went to readjust them yesterday.... man were they tight.
I haven't started since I readjusted them.... a little nervous.

My question is: What will I hear if they are really bent?
I'm guessing a tap dance.:eek2:

All you major motroheads out there please give me your 2¢

[2004exrider]

I guess just start it up and see if it sounds any different.

Jimmy

[exboomer]

Make sure you set the valve clearances correctly (engine cold and also setting them a little on the loose side is better than too tight). Start it up and listen. If the valves (stems) are bent, they would probably stick open therefore your engine wouldn't run.

[johnsls]

Thanks exboomer,, that the kind of info I was looking for.

[400exMO]

Don't set them alittle loose or to tight. Set them exactly on, it's easy. Once you get them set perfectly start it up and it should be fine. If the vavles bends it would have already bent. Just be ready to kill it if you hear something weird.

[johnsls]

I set them tight enough so I was able to get the gauge out but not soo tight that I had to pull hard. LMK

[exboomer]

When I said "setting them (valves) a little on the loose side is better than too tight". I was refering to the resistance felt on the feeler guage and not setting the valve clearance outside the recommended spec one way or the other. Anyway, it sounds like johnsls has it handled.

[johnsls]

Well I'm gonna have to have a friend of mine listen to it,, to me the ticking is just as loud,,

I also installed a UM air box w/ outterwears lid (open)

I understand its cold out but I can barely give it some gas and it stalls,, I also let it warm up first,, but it still keeps stalling.
PRIOR to the install of the UM box I was still able to rev it.

So either I bent the *****Z outta my valves or its gettin too much air.

I've got a 170 / 42 jets (with addt'l mods below)

I may have to repost this

[dariusld]

Originally posted by johnsls
"Hey genious you didn't take it to TDC" (top dead center)

So I went to readjust them yesterday.... man were they tight.
I haven't started since I readjusted them.... a little nervous.

My question is: What will I hear if they are really bent?
I'm guessing a tap dance.:eek2:

All you major motroheads out there please give me your 2¢


The scenerio you are describing wouldn't bend a valve. And I don't know why they would be tight, if anything they would be extra loose. Your not telling us something.

If they are bent your bike wouldn't idle very well.

[johnsls]

Originally posted by dariusld
The scenerio you are describing wouldn't bend a valve. And I don't know why they would be tight, if anything they would be extra loose. Your not telling us something.

If they are bent your bike wouldn't idle very well.

OK then, When I went back to readjust them,, I had to loosen them with the screw driver at least 4 or 5 turns out just to get the feeler gauge in.

Does this help? Trust me they were super super tight. Now it barely idles.

Maybe they aren't bent but I just figured they were due to how tight them were. Let me know.

[cals400ex]

it makes no sense that the valves were tight???? if the bike was not on TDC when you adjusted them the first time then you would have needed to loosen the valves a lot for the feeler guage to fit in because there would be no slack to put the feeler guage in if you were not on TDC. you need to put the valves on TDC on the compression stroke and go from there. if you are not there, then your valves will be off. if the valves are ticking still, i have a feeling they are just loose. tight valves should not make noise, loose ones will. when you are on TDC of the compression stroke is when your valves will be the loosest. anywhere else they will be tighter. at TDC your cam lobes will not be putting any pressure on the rockers so the valves will be fully resting and not being pushed down at all. hence, you can fit the feeler guage in when you are on top dead center of the compression stroke. if you are not on the compression stroke you are just going to have to do it again.

[exboomer]

Make sure you are on the compression stroke when you align the TDC mark, you could be 180 out. Set the valves to spec. The valve trains on these 400ex's will tick and make noise even if the valve clearance is set dead on. It's normal. Do a compression test and go from there. Your sputtering and stalling problem sounds fuel related (carb).

[johnsls]

All of what you said makes sense.

I have already readjusted them at TDS, (this was not done the first time)

I kinda thought they might have bent because they were so tight and I ran the engine to listen and hit the throttle a couple times.

So you all seem to be saying that more than likely the valves are NOT bent. Right?

I turned the crankshaft to TDC (this time I looked to make sure)
Then I adjusted the valves so the feeler gauge what a little tight to pull out. Is this OK?\

OR should I tighten them more so the feeler gauge has to be pulled on a little harder to get it out???????????

I need to probally adjust my fuel screw, currently it 2 1/2 turns out.

Thanks for all your help

[dariusld]

Some times to make sure I'm at tdc, I to put a wire hanger through the spark plug hole and touch the top of the piston. When the hanger starts to drop after reaching the highest point, the flywheel mark should line up.Careful, you can scratch the side of the cyliner this way.

[johnsls]

NO I'm not going to do that.. My mistake was guessing that it was at TDC.... Instead of just taking the cap off and looking inside to be sure.

[exboomer]

The TDC mark behind the left cover will line up on the compression stroke and the exhaust stroke. You want it on the compression stroke. If its on the exhaust stroke, the exhaust valves will be slightly open and you cant properly set the clearance, the exhaust valves wont have clearance because the cam is holding them open. As far as the feeler gauge, you want to feel some resistance but you shouldn't have to pull very hard to remove the gauge. If the valves are set correctly and you have good compression, look elsewhere for your problems.

[AZ_TRX400EX]

If your problem started after the UM Airbox with no lid install then you need to adjust your Carb. You are getting alot more air into your carb than before. If you double checked TDC and your engine is running then your valves are not bent. My quad has always had ticking and it runs like a champ.

[STEVENJANNA]

WOW So this is what you did while we were away!!!:eek2:

[johnsls]

;) Its amazing what a retard can do with a few tools in his hands.