Valve Shim help

[kamikaze]

Took the engine apart last night to do a valve clearance check.

buddy of mine that was helping had feelers that only measured in inches, so i've converted to MM in excel, but I'm now second guessing the numbers.

it seems to me that they are all tight, but the new shim sizes I'm coming up with are all smaller than the current ones, which should make things even tighter if i'm understanding this correctly.



That's a screen shot of my current findings. Data for Intake 3 is missing because it was the only one that was still within spec, so I'm not replacing that one.

[alex.s]

a smaller shim means the bucket sits down lower so when the cam lobe hits it, there is more clearance.

[kamikaze]

I was thinking that too (after I posted the thread of course). do those numbers seem ok then?

[kamikaze]

and if they are good, then the recommended shims that are the closest would be the 2.775 for the intake and 2.70 for exhaust 1-3 and 2.675 for exhaust 4?

[alex.s]

if you have a valve shim kit just put the new shims in and remeasure. it takes 2 minutes.

[alex.s]

quickly:

current shim size: 2.794
current clearance: 0.152
total shim+clearance: 2.946.

from that total, we know what we want our clearance to be, 0.178 (according to you)

so to get the new shim size, subtract our desired clearance from the total,

new shim size: 2.768 (2.946 - 0.178)

you might want to use more accurate measuring tools. and also not use inches.

[kamikaze]

Originally Posted by alex.s

if you have a valve shim kit just put the new shims in and remeasure. it takes 2 minutes.

I don't have a kit. Just want to replace the ones that need replacing, since the dealer has offered to trade in my current shims for a better price on the new ones.

Originally Posted by alex.s

quickly:

current shim size: 2.794
current clearance: 0.152
total shim+clearance: 2.946.

from that total, we know what we want our clearance to be, 0.178 (according to you)

so to get the new shim size, subtract our desired clearance from the total,

new shim size: 2.768 (2.946 - 0.178)

you might want to use more accurate measuring tools. and also not use inches.

yea, the formula isn't what is confusing. that's the simple part. i don't know how much more accurate you'd like to see, but I think a thousandth of an inch is pretty accurate. I wanted to do it all in metric, but we didn't have metric feeler gauges handy, and since it's just a conversion it shouldn't be a problem. The required clearance is from the service manual (0.22 ~ 0.29 mm for exhaust and 0.15 ~ 0.24 mm for intake) so I went with numbers that were close to middle ground.

[alex.s]

thats all fine. just make sure you always double check the clearance with feeler gauges with the new shims in.

[kamikaze]

Originally Posted by alex.s

thats all fine. just make sure you always double check the clearance with feeler gauges with the new shims in.

was planning to remeasure with the new shims. had to order a new gasket for the valve cover anyway, so it'll be a couple days before I get these shims replaced.

[alex.s]

yeah they use those cheap paper gaskets on the 250. they always tear

[kamikaze]

Originally Posted by alex.s

yeah they use those cheap paper gaskets on the 250. they always tear

this one is rubber. I'm also replacing the plug gaskets and exhaust manifold gaskets as well since I've got it all apart.

i don't know how you guys do this with the engine in the bike, so much easier on the bench

[Alex]

@headshrink put together a pretty good spreadsheet awhile back as well:

http://www.ninjette.org/forums/showthread.php?t=73240

[HKr1]

Originally Posted by alex.s

if you have a valve shim kit just put the new shims in and remeasure. it takes 2 minutes.

LOL

[alex.s]

something funny? does it take you longer than 2 minutes to measure 8 valves? if they are all correct it should take about 30 seconds per side

[headshrink]

Originally Posted by alex.s

something funny? does it take you longer than 2 minutes to measure 8 valves? if they are all correct it should take about 30 seconds per side

It usually takes me a day, but that's another story... lol.

[headshrink]

Unless your valve cover gasket is beat up, there is no need to replace it. Same thing goes for the spark-plug gaskets. The crush gaskets on the header though, that could go either way, but I do like keep an extra set of those around, and probably would go ahead with that one.

[alex.s]

it takes you a day to stick some feeler gauges in between some parts?

[headshrink]

Originally Posted by alex.s

it takes you a day to stick some feeler gauges in between some parts?

No - just for all the redos, and unforseen things. I'm getting better at it each time - a day was a bit of an exageration. 1/2 a day may be more accurate.

[kamikaze]

Originally Posted by headshrink

Unless your valve cover gasket is beat up, there is no need to replace it. Same thing goes for the spark-plug gaskets. The crush gaskets on the header though, that could go either way, but I do like keep an extra set of those around, and probably would go ahead with that one.

The old valve cover gasket was leaking oil, and the plug gaskets were getting kinda hard. for what it's worth to replace them I'm not too concerned.

[headshrink]

Originally Posted by kamikaze

The old valve cover gasket was leaking oil, and the plug gaskets were getting kinda hard. for what it's worth to replace them I'm not too concerned.

Good idea then. What year is your bike?

[kamikaze]

Originally Posted by headshrink

Good idea then. What year is your bike?

2010. called the dealer today to see if the gaskets were in, all were there except one plug gasket that is on backorder with no ETA. after calling all over hells half acre looking for one in stock, finally found one in Ottawa. The wife is going there on holidays next week so i put on on hold and she's going to pick it up.

[alex.s]

just use ducttape

[headshrink]

Originally Posted by kamikaze

2010. called the dealer today to see if the gaskets were in, all were there except one plug gasket that is on backorder with no ETA. after calling all over hells half acre looking for one in stock, finally found one in Ottawa. The wife is going there on holidays next week so i put on on hold and she's going to pick it up.

I'm surprised you are having problems with that valve cover gasket so soon. I wonder if the difference between my experience (2008, still in great condition) and yours is the difference in weather where we live.

The first time I did my valves, it took me a few tries before I had the gasket seated properly. I would think I had it on right, bolt down the cover, which would exaggerate the problem where it wasn't properly seated, etc. My only thought was double-checking that it was installed properly last time, but that is assuming there was a last time. And if your plug gaskets have hardened already, I'm inclined to think you're probably right about needing a replacement. Just thinking aloud....

[alex.s]

Originally Posted by headshrink

The first time I did my valves, it took me a few tries before I had the gasket seated properly. I would think I had it on right, bolt down the cover, which would exaggerate the problem where it wasn't properly seated, etc.

ugh i went through the same thing 3 times the first time i did the valves. so frustrating!!!

[headshrink]

Originally Posted by alex.s

ugh i went through the same thing 3 times the first time i did the valves. so frustrating!!!

I also miss-read the SM and put blue locktite on the cam cap screws (don't do that!). I was out of commision for a week while I waited for the replacement screws, and I was VERY lucky I was able to get the stripped screw out with an impact hammer. That is a mistake you only make once. So a bunch of stupid stuff like this is why I take a long time. Even when everything goes well, it takes me a while to read, read-read, confuse, re-read, post, etc. to make sure I have the timming correct (hoping next time goes quickly).

[kamikaze]

did either of you guys use any silicone in addition to the gasket on reassembly? when we took the old gasket off there was some silicone on the side closest to the cam gears.

I know it's only a 2010, but i've put ~32000km on it since purchasing it in Aug 2010 so that's quite a bit of mileage for such a new bike. Plus, with the gaskets being cheap, I figure it's worth replacing them. I'll just make sure to look for them sooner the next time.

[headshrink]

I didn't, but I also didn't pull the gasket all the way off either. Unless you are replacing the gasket, I don't think there is a need to pull it off.