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ViragoTechForum.com XV250 Virago xv250 Valve Clearance Adjustment. (SOLVED)

#1:  Virago xv250 Valve Clearance Adjustment. (SOLVED) Author: j0n24 Post Posted: Thu Feb 26, 2009 8:28 am

I'm planing on checking/adjusting the valve clearances in my '07 XV250 this weekend and I just wanted to clear a few things up.

Is it necessary to remove the fuel tank? I've got a full tank and I'd prefer not to remove it if possible.

Which is the front cylinder on this bike? I would imagine the front cylinder is the one closest to the front of the bike - please correct me if I'm wrong.

Which valve is which? Are the exhaust values on the part of the cylinder pointing toward the back of the bike and the intake on the section pointing towards the front?

Any tips, suggestions would also be welcome. Thanks!


Last edited by j0n24 on Tue Mar 03, 2009 11:15 pm; edited 1 time in total

#2:  Re: Virago xv250 Valve Clearance Adjustment. Author: tomcas Post Posted: Thu Feb 26, 2009 9:29 am

Yes, you have to remove the tank, before that the seat, after the tank the air cleaner, then the left pod also. The front cylinder is closest to the front of the bike. The intake valve are in between the cylinders and the exhaust are out board of the cylinders.
Here's some tips-
I just finished checking the valve lash on my 250XV and thought I'd pass along some tips. Some unique tools required are a 24mm combination wrench for the valve cover access plugs, a set of tapered tip bent feeler gages, and two large washers to unscrew the plastic access plugs on the side cover. The washers are used as a screwdriver to fit the slots on the access plugs. The best size washers are .060 thick x 1 1/4 dia for the small timing mark cover and .090 thick x 2" dia for the crankshaft cover. If you try to use a large screwdriver you are bound damage the covers. Contrary to the manual the engine turns counter clockwise at the access cover. Also, the manual doesn't call for it but I think it's worth the effort to remove the entire left side pod with the reed valve and air cutoff. If you have to adjust the rear exhaust tappet you may even want to remove the battery. After removing the chrome covers from the head I suggest to take the time and clean all the road grime from around the tappet access plugs. Otherwise this debris may fall into the head or prevent the o-rings from sealing. A toothbrush dipped in gas together with an air blowgun works very well to get at the tight area at the bottom of the tappet plugs. Overall everything is VERY tight to reach. If you never adjusted valves before you may want to leave it to a pro.

#3:  Re: Virago xv250 Valve Clearance Adjustment. Author: j0n24 Post Posted: Thu Feb 26, 2009 1:24 pm

Okay, intake values on the inside, exhaust values on the outside - got it.

With regards to removing the fuel tank. Can it be removed without draining it? As long as the fuel petcock is "ON" or "RES" I shouldn't have any leakage issue right?

Thanks again for your info.

#4:  Re: Virago xv250 Valve Clearance Adjustment. Author: tomcas Post Posted: Thu Feb 26, 2009 7:46 pm

You are correct, you don't have to drain the tank provided you remove it with the auto petcock still plumbed to the tank with the hoses in place. I alway start by removing the two (I believe) 8 mm head screws on each side, one side holding the auto petcock and the other side holding the fuel pump (I think) to the tank. This leaves more room to pull the vacuum hose and fuel line leading to the carb from the auto petcock. You can then remove the tank with the auto petcock dangling from the tank. You are also correct in qualifiying the conditions of the selector. If left in the prime position fuel will drain without a vacuum present. Removing the tank by this methods works great and doesn't spill hardly a drop.

#5:  Re: Virago xv250 Valve Clearance Adjustment. Author: j0n24 Post Posted: Sun Mar 01, 2009 11:00 pm

Well I successfully checked/adjusted my valve clearances this weekend. Next time, I'm sure it won't take me half as long. I removed the seat, battery, fuel tank (didn't spill more than a few drops of gas despite having a full tank), air filter pod and thermo switch housing (left pod). The rear cylinder exhaust valve is quite a tight fit, but I managed (hence removing the battery).

I used the Cyclepedia online manual to assist with the job, but I have to say the most difficult part was trying to find the TDC on the compression stroke for the intake valve. What I failed to realize is when all manuals say "turn the crankshaft around until you see the intake valve close and then rotate the engine again until you the appropriate TDC marking matches up etc", they mean that a closed valve is actually up. So the rocker arm is in the up position. I was initially reading into it that a closed valve was seated down into the engine not up, and as a result I was not on the TDC of the compression stroke, resulting in the appearance that all my valves were way to tight!!! Anyway, a lesson learned.

I'm going to contact the Cyclepedia people and let them know that a little more clarity should be provided regarding valve clearance adjustment, given that the intended audience are people who require a little more hand-holding than those who just use the service manual.

Thanks for your help!


Last edited by j0n24 on Mon Mar 02, 2009 1:18 pm; edited 1 time in total

#6:  Re: Virago xv250 Valve Clearance Adjustment. Author: Mykola Post Posted: Mon Mar 02, 2009 12:52 am

You can also refer to the markings on the flywheel to find TDC for each cylinder.
-Remove the timing plug
-For front cylinder TDC you want to align the arrow on the crankcase cover with the "│├" mark on the flywheel like below:

˅
│├


-For rear cylinder TDC, "│"

˅

#7:  Re: Virago xv250 Valve Clearance Adjustment. Author: j0n24 Post Posted: Mon Mar 02, 2009 1:21 pm

Hi Mykola,

I was indeed matching the flywheel markings as I rotated the crankshaft. But matching the markings on the flywheel is not enough - as the intake valve has to be at TDC on the compression stroke to get an accurate measurement. To ensure I was on the compression stroke, I had to wait until the intake valve was closed (up out of the cylinder) before cranking around again to match up the flywheel markings.

#8:  Re: Virago xv250 Valve Clearance Adjustment. Author: tomcas Post Posted: Mon Mar 02, 2009 6:52 pm

Finding the compression stroke is very easy. Pull the plugs, place your finger over the spark plug hole of the cylinder you are adjusting and feel for compression as you rotate the engine in the normal direction. From there just continue rotating until the appropriate timing mark lines up.

#9:   Author: grazingazer Post Posted: Mon Mar 02, 2009 7:00 pm

yep

#10:  Re: Virago xv250 Valve Clearance Adjustment. Author: j0n24 Post Posted: Tue Mar 03, 2009 8:25 am

tomcas wrote (View Post): Finding the compression stroke is very easy. Pull the plugs, place your finger over the spark plug hole of the cylinder you are adjusting and feel for compression as you rotate the engine in the normal direction. From there just continue rotating until the appropriate timing mark lines up.


That's a great tip ... thanks!

#11:   Author: Richdd Post Posted: Thu Mar 05, 2009 3:32 am

I use the same technique finding TDC. If I cannot get the proper feeling, I carefully place a philips in the hole and watch it come up.
This technique has to be done very slowly, because you can casue damage with the screw driver if it binds in the spark plug hole.

#12:   Author: dodge Post Posted: Tue May 25, 2010 9:23 pm

What is a good brand of feeler gauge? I notice most do not offer feelers in the correct gap sizes?

#13:   Author: tomcas Post Posted: Tue May 25, 2010 9:38 pm

dodge wrote (View Post): What is a good brand of feeler gauge? I notice most do not offer feelers in the correct gap sizes?

There's no difference in feeler gauges. They are either made from work hardened stainless or hardened steel and the manufacturing tolerances are way tighter than you need. The only exception is crap Chinese made feeler gauges in which case all bets are off and anything is possible.

#14:   Author: Msasani Post Posted: Wed May 26, 2010 9:09 am

Actually, you don't have to remove the tank. Just remove the seat, remove the bolt that keeps the tank in place, and then prop it up as high as it will go without forcing anything -- a few inches. Use something soft like a folded up newspaper or a towel to keep the tank propped up without scratching any paint. You'll have lots of room to work.
ViragoTechForum.com XV250 Virago xv250 Valve Clearance Adjustment. (SOLVED)


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