Checked valves...

and now its harder to kickstart? ... did I get them too tight? It's just like it's got a hard spot that is kind of hard to kick thru, real hard using all my weight.

I made sure it was on the compression stroke (i'm pretty sure) and it was on TDC but not perfect, because I couldn't get it to stop exactly on the | T mark.

Using the engine bolt, I went through the strokes a bunch of times trying to make sure, but the valves did have a little play, so I thought I was in good shape... I got the new NGK 9z sparkplug in, and she purred like a kitten

When riding it today I could really tell the difference, but seems like I can still here the rockers or valves making noise under much throttle, or either the timing chain, so idk. Also, did you guys torque up the locknuts on the valve adjusters? Because I just used a boxed end wrench... I heard one guys came off and wedged in the cam.:thumbsup: This job did take me a while, but wasn't that bad, it was my first time doing it. Should it have that hard spot though, when starting it??

thx for any help y'all.

Also I went by my Haynes service maual, it said .002"in. and .003"exh. it may have been vice-versa, not sure, but is that too tight? or correct?

Take a look at the post in this forum by durandl on lubricating suspension and valve adjustment, he has it nailed.

Also I went by my Haynes service maual, it said .002"in. and .003"exh. it may have been vice-versa, not sure, but is that too tight? or correct?

The XR400 service manual says

IN: 0.004 +/- 0.0008 inches

EX: 0.005 +/- 0.0008 inches

I agree that getting the engine to stop at the T mark is not easy, but it's worth it.

Use a hex socket connected to an extension bar, plus a ratchet or normal bar-plus-socket. Forgive my imprecise names, but I do my mechanical work in spanish :-P

When you have the engine coming up to the mark, you'll have to fight the counterweight or whatever it is inside the engine that makes this thing hard to align.

Creep up to the mark, and then hang something from the ratchet's end, so as to give it enough toque to hold it steady, but not enough to pull the mark past its point.

Just don't bump the whole Rube Goldberg aparatus with your knee, and check the alignment before moving on to the next valve.

My first adjustment:

http://flightoftheplatypus.blogspot.com/2006/11/valve-adjustment.html

My second valve adjustment, perhaps clearer than the first.

http://flightoftheplatypus.blogspot.com/2007/06/lubricating-rear-suspension-and-valve.html

d.

If your cam is stock you must be sure that the auto-decompressor is not contacting the rocker on the right exhaust valve. I've messed up on this valve twice. Ended up @ .009-.010 both times. Shouldn't hurt starting any but it makes lots valve noise when running. Btw, .004 intake/.005 exhaust is correct.

This job is easier if you have a HELPER to help you hold the alignment on the "T" mark. The reason it is hard to hold there is the MAGNETIC effect on the flywheel.

Get a friend and do it right !!!!!!!!!!!!!!!!!

CHeers,

First off, the bike is a XR250, right? Clearances are .003" in. and .004" ex..

The hard spot is TDC. Use your compression release to get a little past that point and kick from there.

The guys have it right for keeping the flywheel at TDC while checking the valves. Leave the socket wrench on there as a counterweight. I usually also have to add a short cheater pipe to it to get enough weight.

If your cam is stock you must be sure that the auto-decompressor is not contacting the rocker on the right exhaust valve. I've messed up on this valve twice. Ended up @ .009-.010 both times. Shouldn't hurt starting any but it makes lots valve noise when running. Btw, .004 intake/.005 exhaust is correct.

The shop manual indicates to disconnect the decompressor cable.

What I do is unscrew the 8 mm bolt that holds the assembly onto the valve cover, so there is no chance at all that the manual decompressor will screw with the adjustment.

d.

Alright, hey thanks you all for all the replys...my decompression lever is already unhooked on my bike, but the little swivel thing is still connected with the spring on it, could this possibly engage it? Can you hear it "kick in"?... it may have but... I rode it a little today and the valves were making some pretty loud ticks and tocks, kinda made me go: ahh damn, and the big question here is: Is there supposed to be a hard spot at top dead center, and I mean HARD... I can sometimes play with the kickstarter and get it to move a little easier - but it does make it a b*tch to start.

But it generally starts in only 1-3 kicks, not always :thumbsup:

And will valves a little too tight hurt anything? What do ya'll go with on your older pre 96 XR's?

mines a 95.

Also, when I first started my bike it wasn't Ticking so loud and I couldn't even notice the noise, but now......

And yes my bike is Xr250 and I adjusted my valves at.002"intake and .003"exhaust.

My manual had 96 and up XR's a different valve clearance as I recall, I think looser.

and that breaker bar sounds like some good advice, weight the flywheel at tdc, I had it there but it wanted to rock back and forth therefore wasn't perfect..

does anyone know why 96 and up XR250 and 400 have .004intake and .005exhaust valve adjustment specs, while 86-95 are .002 and .003?

just curious....

Completely revised engine. Not the same engine.

Sorry, I only have a manual for the 96-04. Can't help you with specs for previous years.

no specs on the 86-95 yet??

Are my specs right?!

One more question I would like to find an answer too... do the valves tend to get tight after operating, and do the pre96 bikes prefer to be adjusted at .004 and .005?

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