Valve Clearence help!

Ok guys, so I finally got my valve cover off and got a look at my top end for the first time. For having 15,xxx miles on her the head looks pretty clean! My only question is what do I optimally want my valves to be at? I know intake clearances are .10mm to .20mm and exhaust .20mm to .30mm, But my feeler gauge set goes from .10mm to .12mm to .17mm to .20mm so those are the only 4 I really have to work with.(I guess I need a better gauge set no?) The intake valve farthest from the cam seems to slightly stick at .12 while the intake valve closest to the cam sprocket seems to stick a bit more at .12, making me think that that one is closer to .10. When I try getting the .17 gauge into either of the intake's it will not fit at all. I know that valves will usually get tighter over time rather than looser, so I guess what I am getting at is should I shoot for somewhere around .15 for the intake valves and .25 for the exhaust?? .10 to .20 seems to be a decent gap, how precise do I need to be? I am guessing very but this is my first time doing all of this so any help would be appreciated... thanks!!

P.S. Exhausts are both at about .20 on the dot as well, time to loosen everything up I guess...

I would change the exhaust for sure and it wouldn't hurt to change the intakes too. Get a better guage so you know exactly what they are and keep an eye on them a little more often with that many miles on the motor. If they keep getting tighter, you will know that your valves are wearing down and time for a rebuild.

Do u have any thinner feeler gauges u can use to double up. Eg. 10+5 will give u a .15 gauge etc. It works ok for me.

get a good feeler guage set.sounds like your intakes are getting close.you dont have to reshim now but i would if it were my bike

and keep your air filter clean once you have them set. when i bought my drz it was too late and i had to get the head remachined to stop the clearances tightening constantly. bad filter is like sandpaper on the valve seats.

Do u have any thinner feeler gauges u can use to double up. Eg. 10+5 will give u a .15 gauge etc. It works ok for me.

Smart idea man, never thought of that. :ride:

and keep your air filter clean once you have them set. when i bought my drz it was too late and i had to get the head remachined to stop the clearances tightening constantly. bad filter is like sandpaper on the valve seats.

Ya, mine has 15,xxx on it, I'm hoping for the best, but fearing the worst...haha

If the clearances are in tolerance there is no need to be more precise than that. And no need to adjust. Actually close to min clearance is good. In inches the IN are .004 to .008 the EX .008 to .012. It is easier to think in inches and the feeler gages come in increments of .001. What you should do is measure, record and track. If this is the first measurement, you have no idea of how they have changed (if at all) for many thousands of miles.

Ya maybe, only thing is I am trying to diagnose a knocking sound that has suddenly appeared after putting only 200 miles on the bike. If I adjust now, then check again in 500 miles and they are tight again I probly will need the head worked on and mind as well put a weisco and new base gasket in while im in there. That is my thinking anyways.

Do I need to know what sized shim's are in my motor now before I can calculate what new ones I need? I am at .12 Intake and .20 for exhaust. I am aiming for .15 intake and .25 exhaust. So I need .3mm and .5mm more clearance. I'm going off the FAQ write up but still not quite getting it. lil' help anyone??

I kinda get it, pull out old shims new shims must be .3 and .5 larger than old ones, but if aftermarket shims only come in .5 increments, does that limit me to either having .12 or .17 clearance on my intakes?? I guess I can order oem shims from suzuki??

I kinda get it, pull out old shims new shims must be .3 and .5 larger than old ones, but if aftermarket shims only come in .5 increments, does that limit me to either having .12 or .17 clearance on my intakes??

Yes you need to know what is in there now.

Yes, using available replacement shims, it limits your adjustment choices.

0.03 and 0.05mm. I'm telling ya, it is easier to think in inches if you have been doing it all your life.

Just to add to the confusion, standard practice in mm is to precede the decimal fraction with a zero. In inches this is not the case. example: 0.05mm equals .002 inch

Suzuki OEM service replacement shims come in 0.05mm increments. Only the factory used 0.025mm increment shims.

Ya maybe, only thing is I am trying to diagnose a knocking sound that has suddenly appeared after putting only 200 miles on the bike. If I adjust now, then check again in 500 miles and they are tight again I probly will need the head worked on and mind as well put a weisco and new base gasket in while im in there. That is my thinking anyways.

"Knocking" is not a noise that is associated with valve clearance.

If the valve clearance is tight it won't make extra noise, but if it gets to zero it can cause running/starting issues.

If the valve clearance is large there can be a bit of a rattle from the head area.

Have you done the locktite fixes? Balance shafts tapping cranks have been described as knocking before. <--Bad

When does it knock? If it knocks at low rpms under load that is piston slap. It is better for the engine to keep the revs up more but the sound is normal for these engines.

Also use a mechanics stethoscope or piece of tubing to try to localize the source of the noise.

I kinda get it, pull out old shims new shims must be .3 and .5 larger than old ones, but if aftermarket shims only come in .5 increments, does that limit me to either having .12 or .17 clearance on my intakes?? I guess I can order oem shims from suzuki??

The number on the shims is in mm. Example 305 is 3.05mm Next size smaller to increase the clearance would be 300 (3.00mm).

245 is 2.45mm, if the clearance is small, subtract what you need from the shim. For example if the clearance is 0.09mm and you want 0.15mm, you will have to chose between 0.14mm (240<--Yes) or 0.19mm (235) as the shims only come in 0.05 increments.

It will generally only be a size or two either way unless you rebuild the head.

If you can find a set of metric feeler gauges it makes it easier because the increments are also 0.05mm. That way you can see what the next size bigger or smaller shim would fit like just by moving to the next feeler.

Edited by slowriding
"Knocking" is not a noise that is associated with valve clearance.

If the valve clearance is tight it won't make extra noise, but if it gets to zero it can cause running/starting issues.

If the valve clearance is large there can be a bit of a rattle from the head area.

Have you done the locktite fixes? Balance shafts tapping cranks have been described as knocking before. <--Bad

When does it knock? If it knocks at low rpms under load that is piston slap. It is better for the engine to keep the revs up more but the sound is normal for these engines.

Also use a mechanics stethoscope or piece of tubing to try to localize the source of the noise.

No, locktite fixes were going to be next on my list before I button her up. It knocks at idle and all the way through the powerband (hoping locktite is the cure). I know what you mean by that piston slap at low rpm as well, I get that too but I am now keeping the revs up and learning how to ride her a bit better. As far as valves go if I am at .12 intake and .20 exhaust, I think I should at least shim the exhaust right? .20 is the bare minimum and that is exactly where I am at.

In my opinion - no. If the EX valves are at 0.20mm they are in spec and do not need adjustment. Plus if you have knocking, you have other bigger problems. Don't waste your time re-shimming vales unless it is just something you want to do as a learning exercise.

Locktite fixes are a higher priority by far. You need to know if the primary nut or counterbalance shaft nuts are loose and if not you need to check your crank for play. You can give the crank a simple check by turning the flywheel 90 degrees to the timing mark and rocking it back and forth feeling for play. A straw down the spark plug hole might give you an idea if the piston is moving with the crank.

Ok I think your right, I will do that tomorrow after work, about the locktite fix, do I really need an impact screwdriver to get the cover off?? That is something I do not have, Would an electric drill work? I would hate to have to take my bike to the shop just to get those bolts off...:ride:

an impact screwdriver is a relatively inexpensive tool that is hit with a hammer, it allows many difficult fastners to be loosened easily. you may not "need" it but you may damage the fastener without it

ImpactDriverWithBits.png

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