How-to : Valve Adjustment
 

The following "How-to" as been adapted for this forum from: http://i2kdave.wordpress.com/2009/07/23 ... djustment/
All credit should be given to the original poster, i2kDave and board member Brucea for finding it.

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Here are the tools you will need:
6mm allen wrench
flat wrench, or other similar tool
3? extension (optional)
ratchet
set of feeler gauges
8mm wrench
22mm socket
17mm socket
10mm socket
valve adjuster tool (09917-14920)
spark plug wrench

http://i56.tinypic.com/2czr8fl.jpg


First, remove the two 10mm bolts holding the back of the gas tank.

http://i52.tinypic.com/ma80lv.jpg


Make sure the fuel valve is in either the “ON” or “RES” position, and disconnect the fuel hose and vacuum hose. Now you can lift the gas tank off and sit it aside.

http://i51.tinypic.com/2r5ds43.jpg


Remove the left cylinder head cover cap with the 6mm allen wrench.

http://i52.tinypic.com/xbzs5u.jpg


Disconnect the spark plug and remove it with the spark plug wrench.

http://i51.tinypic.com/qxmmxh.jpg


Remove the four 10mm bolts indicated by the arrows to remove the valve inspection caps.

http://i52.tinypic.com/sl5ykh.jpg


Next, you need to get the piston in the correct position before checking the valves. Remove the valve timing inspection plug with the 17mm socket, and the generator cover cap.

http://i53.tinypic.com/egbont.jpg


I had to loosen the cap with some WD-40 and removed it with a flat wrench I had in my toolbox.

http://i51.tinypic.com/2s67jf8.jpg


Using the 22mm socket, turn the crankshaft until the “T” mark aligns with the arrow on the generator cover, and the piston is on the compression stroke. You can tell when it’s there by plugging the spark plug hole with your finger and rotating the crankshaft until you feel pressure on your finger.

http://i55.tinypic.com/153pv74.jpg


Once all that is done, you can start checking the valve clearances. You’ll be checking the space between the valve stem and the adjusting screw, indicated by the arrow. Be aware, the intake and exhaust valves have different specs. Just to clarify, the intake is toward the rear of the bike, and the exhaust is toward the front.

http://i53.tinypic.com/2uj5fmw.jpg


If any need adjusting, loosen the locknut with the 8mm wrench and turn the adjusting screw with the valve adjuster tool until it has the proper clearance. Try not to let the screw turn while you’re tightening down the locknut, or you’ll have to adjust it again. Trust me, I speak from experience.

The exhaust side isn’t that difficult to work with, but the intake is in a very tight location. I moved some of the wires and cables out of the way and still had a hard time getting my fingers in there. Do yourself a favor and buy some angled feeler gauges. Mine are flat, and that made it even more difficult, not to mention that they got all bent up in the process.

Once you get them all adjusted to spec and the locknuts tightened down, rotate the crankshaft 720° and check the clearances again. If everything is good to go, just put everything back together and you’re done!

Re: How-to : Valve Adjustment
 

Nice, i think i will tackle this soon being i dont know if its ever been done from the previous owner.

Re: How-to : Valve Adjustment
 

This pretty much covered everything you need to know. It's a simple process, once you find TDC.

Re: How-to : Valve Adjustment
 

I'm in the process of trying to adjust the valves unfortunately getting that cover off on the lower left of the housing is proving to be a real pain... My question is this: where in the pictures are you using this valve adjuster tool (09917-14920) tool?

Is this the same thing someone made with a cork a screw??? How is it used?

chandlerbingfl

Re: How-to : Valve Adjustment
 

My question is, what is the adjuster tool? ie its shape
I assume thats a long reach socket or a long socket for a [strike:35my34yo]hex nut[/strike:35my34yo] (I looked again, it looks like a square end (internally shaped square on the tool) on a short screwdriver handle). Presumably a short handle to allow the job to be done with the tank in place?
If the tool isn't that maybe someone could provide some illumination or better still a close up picture of the valve adjuster tool?

edit (when I looked again) to "chandlerbingfl" in the last picture provided, when you do the measurement with the gauges, the tool looks like it goes over the square piece sticking out above the locking nut. So if the measurement is out of spec, I'd imagine with the ring spanner (8mm) in place holding the adjuster tool in place, loosen the locknut, measure with the feeler gauges, then adjust the square end with the tool if necessary, and then tighten the locknut again (and then measure again to confirm :)).

If i'm wrong feel free to correct me.

I'm not sure where I can get one locally?, or what size is it square? (instead of me having to open it all up to check) I'll look online and check the part number and see if there is a place local that does them and if they are readily available online.
While I'm sure something could be bodged to work, I prefer not bodging stuff, right tool for the right job and all that.
:)

And so I dont seem lazy, a quick google throws up a few answers, here included.
viewtopic.php?f=10&t=5959

Re: How-to : Valve Adjustment
 

Thanks for the reply.... I clicked on the link you provided and my question is what is the screw in the cork for? The pictures in this thread do not show any special tools required other than valve adjuster tool (09917-14920) which is what I am assuming the screw in the cork is for. Unfortunately the pics in this thread do not show it being used.

I also found this page http://i2kdave.wordpress.com/2009/07/23 ... djustment/ which shows a real valve adjuster tool but it isn't used in the pictures as well.....

I did finally get the Generator cover off.....my only concern is this valve adjuster tool......that I don't know what its for and the pictures of how to adjust the valves do not show...

Thanks again,
chandlerbingfl

Re: How-to : Valve Adjustment
 

The last pic shows the end of the rocker arm. There is a lock nut with a small square just above it. Loosen the lock nut to allow the small square to rotate. It is the adjuster for the valve clearance. It is a threaded item that goes through the end of the rocker arm and makes contact with the top of the valve stem. The arrow points to the point where you make the measurement with the feeler gauge.
The cork and screw is just a Robertson head screw screwed into a cork(for grip). The head of the screw will fit the square adjuster so it can be turned. I think it will need to be a head to fit a # 2 Robertson screw driver. Some one will correct me if I am wrong.

Re: How-to : Valve Adjustment
 

A shrader valve cap works well & you can use a short valve stem on the end of it.
I have the proper factory adjuster & it's to long to use on the intake valves without moving wiring out of the way.I ended up using the shrader valve,it works much better.



http://s10.postimage.org/z1nc4m1s5/images.jpg

:)

Re: How-to : Valve Adjustment
 

I wouldn't have thought of that, I'd have guessed it was too small, but in my defence, I dont know the dimension of the square nut either, I haven't seen it, but I probably should have.
I'm suprised that has the strength (stainless or not?) to not break off one of those side bits, what do you hold the cap with? a valve stem? a cranked one?
I wouldn't want that or anything off it falling in there.

Re: How-to : Valve Adjustment
 

A short valve stem works well.The adjuster turns very easy,once the nut is loosened.Hardly any effort is needed at all.
:) :2tup:

Re: How-to : Valve Adjustment
 

Once again you all came through with some valuable information for me (and in the long run others like me)! So I gather I might not need the screw/cork thing after all.... I've been frustrated with this from the get-go so....

I finally got the cover of the left side! I ended up using the end of a pair of wire strippers and a vise grip for leverage and it came loose. I am now most of the way to get on with adjusting the valves.

More to come, hopefully I can get this done without bothering you great enthusiasts anymore.....

Always appreciative!
chandlerbingfl

Re: How-to : Valve Adjustment
 

On the last photo above, should a gasket be put on of any kind ?

Re: How-to : Valve Adjustment
 

No,there is a o-ring in the cover.
:)

Re: How-to : Valve Adjustment
 

Thank you blaine

Re: How-to : Valve Adjustment
 

No problem.Glad to help!! :) :2tup:

Re: How-to : Valve Adjustment
 

I'm baaaaaack........ Finally got ahold of a 22mm socket and have the timing mark lined up and finding the valve adjustment specs of IN. : 0.03-0.08 mm (0.001-0.003 in) EX.: 0.08-0.13 mm (0.003- 0.005 in) and I am all set to start but the feeler gauges I have are marked as follows.

The sizes range from .008in/.203mm through .026in/.660mm so just looking at the numbers. Does this mean my set of feeler gauges will not work?

Maybe it's my lack of knowledge on these things but I'm guessing I need a different set of gauges unless someone here can tell me otherwise.

Also are these valves opened by a common tappet? I believe so but the more I get into this the more questions I have....

Much thanks!
chandlerbingfl

Re: How-to : Valve Adjustment
 

The feeler gauges should work for you. I am assuming you have the flat blade type. If you need something thicker just pick any 2 guages that add up to the needed number and slide them in together.
The rocker arm is sort of a "Y" shaped affair. The top of the Y has separate adjusters for each valve. The bottom of the Y is common. You will have 2 exhaust valves with separate adjusters on a common rocker arm. Same applies to the intake valves.
Do take a look at a fiche diagram that Ronayers.com can provide online. It will give you a good view of the entire assembly before you dig into it so there won't be any surprises.

Fiche files have been of immense help to me in the past when I am in unfamiliar territory.

Re: How-to : Valve Adjustment
 

Thanks WW! I have angled gauges but if you say I can put 2 together - which ones?

The gauge set I have starts at (in inches) .008 .010 .012 .013 .014 .015 .016 .018 .019 .020 .026. If the exhaust gap shpuld be 0.003in - 0.005 in, it appears to me that even my thinnest is not thin enough. Or is my thought process muddled due to my frustration. Unfortunately if I had ~$150 I'd just have a shop do this but I don't so any and all help is greatly appreciated!

Thanks again,
chandlerbingfl

Re: How-to : Valve Adjustment
 

Take another look at your gauges to be sure of what you are reading, ie,. make sure of the decimal point and whether it's in. or mm.
If they are too big, then you need a thinner set.

Re: How-to : Valve Adjustment
 

Yeah I sort of figured that would be the case..... Kind of sucks but it is what it is.....

Thanks again,
chandlerbingfl

Re: How-to : Valve Adjustment
 

Did it all work out?

It's a little late but here is a thread with a picture of a valve adjustment tool:
http://www.gz250bike.com/forum/viewtopic.php?f=10&t=45

PS also found a set here:
http://www.motorcycle-superstore.com...-Wrenches.aspx

Re: How-to : Valve Adjustment
 

Pair of wire strippers worked well. Valve adjusted as desired. Thanks for solving this brain teasing issue.

Have just taken a motorcycle tune-up class from one of the local community colleges and decided to attempt the valve clearance adjustment. Thanks for the sticky post, Jonathan! Woohoo!

Had a lot of frustration because I was using flat feeler gauges and just so much difficulty getting the right angle and feeling the "drag". However, finally got the job done and am definitely hearing more valve noise (there was NO gap at all at the intake valves when I checked).

I have ordered the Motion Pro angled feeler gauges for the next go around. I was actually surprised to read in the manual that the clearances should be checked every 3,000 miles. My teacher said, in general, for this type of valve system (post and locknut, as opposed to shims), it should be done every 5,000 miles. I hadn't had any kind of valve check by a shop for much longer and I am feeling grateful I haven't seemed to destroy anything!

Considering how many failures have been occurring here on the forum that are valve related, I'm going to start just suggesting the factory recommendation. I've never been around a vehicle that actually needed that much check up on something like valves. But it's certainly easier than having to replace the head.

I had mine for roughly 8,000 miles and I only did the post break-in inspection. There are guys who have been riding their GZs for years and only ever done the initial check. But I guess somewhere along the way the law of percentages was bound to catch up with us.

Check your valve clearances every 3,000-5,000 miles.

Is it a gz thing for the valves to be way too tight? When I got my valves checked at 6 or 7k they had no slack.

I work on chines scooters an 90% of the times wen they don't start ore run like crap the valves are to tight

Just the nature of the design. It is an easy adjustment overall compared to the shin and bucket design of some other engines. My Vstrom had the shim and bucket design. No adjustment needed after 25,000 miles but would need the cams removed if the shims were in need of replacing. One fellow Vstrom rider had over 100,000 miles with no adjustments needed.

As a side note. There are some cars on the market with shim and bucket designs now. That should be a real shock to the folks who bought an economy car only to be hit by a very expensive maintenance now and again.

Yes On motorcycles the valves get tighter as the valve sinks into the head.That is why if you don't hear a little valve noise it's time for a adjustment. (unless it's a Honda with hydraulic lifters) ;) :)

So with all the action in this thread recently I decided to check and adjust my valves. Now im 99% sure I've gotten everything adjusted within specs, but when I just took it for a test ride it bogged down and died as if it was running out of gas. Could start it again with the petcock on prime but if i turned it back to the normal on position sure enough it died again a few minutes later. Also when I brought it back into the garage it smells like it's running too lean, a burnt kind of smell.

Any ideas on what I could have screwed up while doing a fairly straightforward maintenance?

EDIT: Just a tip to all the geniuses like me out there, REMEMBER TO RECONNECT THE VACUUM LINE TO THE FUEL PETCOCK. Problem solved :P

After adjustment, the bike runs much better. I'm getting a lot more range in the gears. It's pouring rain right now so I only went around the block a few times, but I easily got up to 30kmh in first gear whereas before I was lucky to get to 20 before the engine wanted to explode. Second gear took me to 55 rather than 40 like before the adjustment. Very glad I decided to do it today as I had just been procrastinating on it the past few weeks.

:clap:

Great job, well done!

Hahahah. Awesome. Glad you got it sorted.

"turn the crankshaft until the “T” mark aligns with the arrow on the generator cover"
Can someone point at the "t" mark and the "arrow on the generator cover', please?
newbie trying to do some valve adjustement here and I'm having a hard time seeing those..Thank you

I do not have a picture to show, but I will attempt to direct you. Standing on the left side of the bike, looking down at the generator cover, look just above the inspection bolt on the cover. Some times it is hard to see because of dirt, corrosion,etc. The mark is more of a triangle shape than an arrow. I hope this helps you. If not, please let me know and I will try to find a picture for you.

I just did mine, closed everything up, fired it up and the exhaust sounded like shaking pennies in a tin can, so I soon came to realize that my adjustments were way off and too loose. I just re-did them pulling them closer to the smaller size of the spectrum which yielded great but such different results. The changes that I've noticed immediately are that I can now reach 65mph in 4th gear and shifting up doesn't really add speed but more maintains it as opposed to getting up to 50mph and shifting up to get to a consistent 65 unless I had the help of a hill. My cold starts now use very little choke for a minute and then it is able to run with the choke open as opposed to having to keep the choke half on and decreasing it slowly for about 5 min for consistent idle before the adjustment. Now I also do not get a backfire after shutting a hot engine, unlike before when it would happen every time. Also I ordered the 16t sprocket before all of this and am now wondering if 5th gear will be completely useless, but I'm ok with that as long as 4th can get me to 65mph at least. Anyway, thoughts or comments about any of the above?

I am concerned about your lack of power in fifth gear. I have a '09' GZ and on the flat I am able to reach 75 to 80mph with the 16 tooth sprocket. What are your gap measurements on the intake and exhaust valves? Also, have you checked your carburetor for build up?

I can't tell you "exact measurements" but I took the feeler gauge that was the midrange for both intake and exhaust and made it so that it had a decent pull to get it out for all 4 valves, rotated it twice, checked re-adjusted, rotated, checked and closed it up. It was a struggle to get the same feeler gauge back in after tightening the locknut, but the minimum size tolerance would go in with some finesse so I know atleast it's in the range, closer to the smaller side. Like I said I noticed the difference just in the noise from the first failed attempt. Oh btw, I punctured the inspection plug so for now I plugged it with some plumbers epoxy, but need to find one asap. I've been trying to perform maintenance type of jobs on this bike as I can and I haven't looked into the carb just yet. Gotta see if theres a sticky for that on the forum. Also I didn't mention that I am 6'1 with no windshield so there is a decent amount of wind drag against my torso, which could also diminish the amount of torque that 5th gear has.

Your intake valves should be about .002 and your exhaust valves at .004. I am 6'0 and 170 lbs. with no windshield. You might want to add some Seafoam to your fuel tank. It will help clean out your fuel system. It will take a couple tank fulls to get a good start. That may help clean out some of the crud.

I've followed the shop manual, so I set the clearances within range. I put about 2-3 sea foam tank treatments already and plan to kill off the bottle and see if that got me anywhere in the next few tanks. I need to check the spark plug gap too just in case, or just replace it. However, I just got my 16t sprocket today, so we'll see how it likes the next size, fingers crossed. :ride:

Do you guys know which direction the engine should be turned. Its not mentioned anywhere - even in the service manual. Some engines are very finicky about not turning it in wrong direction - possibly not case here but still - I'd like to know if engine turns clockwise or counter (looking from generator side - left side). Thank you.

Get the rear wheel off the ground and slowly turn it while in gear. Observe the rotation of the marks etc. That should work well enough to continue with the valve adjust.