HELP! 250sx valve clearance? Screw Missing?!

[k00leo]

Alrigty then. I need some big help here.
My 1985 Honda ATC 250sx has ran “off” since I got it. Maybe it’s the carb, maybe it’s the valve clearance, maybe it’s an air leak, I’m not quite sure.
I decided to check the valve clearance to see if something was off.
When I was taking off the two plates I came across this:

Carb side
http://img.photobucket.com/albums/v310/k00leo/IMAG0262.jpg
Exhaust side
http://img.photobucket.com/albums/v310/k00leo/IMAG0261.jpg

I check the manual and even though the pictures are pure poo, it seems that there are two screws that are supposed to be there, correct? So my motor is missing the front valve clearance screw?
More important, what the heck happened to the screw? Could it have fallen down into the motor?! Ugh!

[the great gazoo]

I've got some extra top end stuff,PM me & I'll send you the screw & the nut.

[the great gazoo]

Oh, what about the screw & adjuster? Take the valve cover off & se if it's in the top, & if not take the R side cover off to see if it droped down the cam chain guide(Has that ever happened??)

[k00leo]

Sweet, just send you a PM.

So what does everyone else think? would the missing of this screw and nut cause the 250sx to bog down and not have enough power? it seems that my 250sx has virtually no power. i cant get it up to say... 25-30mph

of course, other things such as a dirty carb could cause the same thing.

[k00leo]

Oh, what about the screw & adjuster? Take the valve cover off & se if it's in the top, & if not take the R side cover off to see if it droped down the cam chain guide(Has that ever happened??)



i just got the bike a few months ago so i honestly wouldn't know if the nut/screw has either dropped off into the motor or the previous owner forgot to put it back in.

i will check the right side cover.

[rdlsz24]

I'm surprised it would even run like that. Your exhaust valve wouldn't be opening right? lol

Rpb

[k00leo]

i'm surprised too, but hey, its a Honda right :lol:

[Dirtcrasher]

The valve would open, just not far enough..... The casting will shhow how long that screws been gone.

Take off your valve cover, it is most likely up there somewhere.

It certainly does affect performance so take a look. Just read the manual when you put it back together and use a thin coat of Honda bond or equivalent and avoid the areas shown in the book so the cam isn't starved of oil.

Only other place I can see it going is down into the right crankcase and sitting at the bottom in there.

Keep us posted!!

[k00leo]

thanks so much for the help!

i'm glad that i can come here and get some great advice.

I will try to find the screw tomorrow.

[Captainwtf]

If you find that screw, That's going to be incredible. In my experience in rebuilding small engines etc... I have NEVER had something like that happen :P

[hondamaniac]

so what happend? lol tell me a story! :D