crf250x marks

Hi recently bought a CRF250X, I felt no power on the bike so I was trying to check my valves clearence, When I try to put the marks align, the punch mark on the gear lines up with the arrow but my piston was not on TDC was in the middle and the marks on the cam gear wasn´t align.

image014.jpg

 

is impossible to get the puch mark match with the piston on the top TDC.

 

 what could be wrong??

Was wondering how you know the piston isnt at TDC when those marks are lined up?

A. Watch it, there are two sets of marks on the gear ont he right side.  You may want to look at the marks on the left side as well, which there is only one set of.

 

B. From the looks of that picture, you are not lined up.

 

C.Even if your off a tad, you should not have a problem checking the valve clearence.   Lobs on the cam should be pointing towards the back of the bike if your in the right place.

 

Jim.

BTW, if your new to this, you'll find this thread helpful:

 

http://www.thumpertalk.com/topic/151755-how-to-check-and-adjust-the-valves-on-your-250-wpics/

 

This is from the FAQ stickie at the top of the forum.

 

Also, either use a bent set of feeler gauges (the last 1/4" is bent at an angle) or run the feeler gauge in from the opposite side when checking the exhaust.

 

The head wall is very close to the exhaust valves and if you try measuring the clearence of the left valve from the left side with a straight guage, you'll find it very difficult to do accurately.

 

Jim.

A. Watch it, there are two sets of marks on the gear ont he right side.  You may want to look at the marks on the left side as well, which there is only one set of.

 

B. From the looks of that picture, you are not lined up.

 

C.Even if your off a tad, you should not have a problem checking the valve clearence.   Lobs on the cam should be pointing towards the back of the bike if your in the right place.

 

Jim.

 

I think you got that part mixed up

I think you got that part mixed up

 

Absolutly right...I got my sides mixed up. :doh:

 

Thanks for catching that.

 

Jim.

When I align the right mark ( picture 1) the piston isn´t on TDC like you see in picture 2

When I put the marks in the flywheel (picture 3) no mark on the right side (Picture 4) but the piston is on the top

 

I don´t know what mark use to adjust timing

 

photo.php?fbid=10151774876960488&set=a.1

crf250x.jpg

Edited by saidortiz

On the right side, you need to rotate clockwise until the marks line up again.  Then you will be at TDC.

 

One the left side (flywheel), the "T" is for TDC and the "F" is for Fire. 

 

You should find that when you rotate clockwise on the right side till the marks there line up again that you are now lined up with the "T" mark with the notch in the cover on the left side.

 

Jim.

When I align the right mark ( picture 1) the piston isn´t on TDC like you see in picture 2

When I put the marks in the flywheel (picture 3) no mark on the right side (Picture 4) but the piston is on the top

 

I don´t know what mark use to adjust timing

 

photo.php?fbid=10151774876960488&set=a.1

crf250x.jpg

Some of the pics are sketchy and cant see too much of it clearly but, try something alittle bit different. Since you have the head removed what happens when you put the piston at the top of the bore, are any of the timing marks close to being lined up?

Keep in mind when the marks on the RS are lined up, the LS TDC marks should be lined up also, if not there is something very unusual going on.

This is going to sound stupid I'm sure but what if he skipped a tooth on the timing chain or the previous owner didn't line it up correctly?

 

Would the bike run so poorly that there would be no question or would it seem to just lack a lot of power to new owner?  I'm new to this and haven't played with engines since highschool a million years ago, so I'm very rusty.

  It would run pretty horrific, but they sometimes do run.  Hard to say without being there.  But often if your off a tooth they won't even start.

 

Jim.

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