Interest in a shim exhange for valve adjustments?

[Bigballsofpaint]

Just curious since a lot of people here end up doing their own valve adjusting. I didnt want to buy a kit for 50+ bucks if i only needed a shim or 2, and i didnt really find a place that sold individual shims. Also most of the shims are .05mm intervals (.002in).

So i thought a bit, i do work in a machine shop, we have tons of tooling, machines, etc. On the valve job we just did all the shims were too large on the exhaust side. Intakes were fine, so i ground the shims down to the desired measurement. All shims are within .0002 of being flat, and within .0005 of my desired size. (i made them so the lash was .010, right in between the tolerance). And the grinder goes in .0005 increments. So its fairly easy for me to ground them to .001 plus or minus .0005, which is .025mm increments instead of the .05mm which the kits i see for usually are.

To cut my story short, would anyone be interested in having me grind your stock shims for a set price, or sending me your cores if you need a larger size and i would provide the needed shim. I would end up trying to buy some of the shims from members here who have done their adjustments and have no need for their shims. Basically send me an envelope with an extra stamp in it with your shims in a plastic bag so oil doesnt seep everywhere, and i send you the shims you need within 1 or 2 days of getting the envelope. Or i could charge double and refund half when i received yours if you needed the shims asap.

Sorry for the long thread, i saw a place who had a shim exchange type deal but either the site wasnt working or they didnt list any details.

[alex.s]

just buy the 3.0 refill kit.

its a horrible idea to grind on the shims.

[Bigballsofpaint]

3.0 refill kit costs how much? the only kit i saw was like 20 and it had 5 shims, 1 of each size. Then the full kit with like 30 shims for 50-60 bucks.

Why is grinding the shims a bad idea again? Not that i doubt you since you usually give good advice on this forum, but if done correctly i see no reason for it not to be perfectly fine. I mean, how do you think they are made in the first place?

[alex.s]

you *can* do it. just like you *can* do a lot of things. but can you tell me how hot the surface of the shim is getting while you are grinding it? no? then how can you tell me how the steel will react to the grinding? how is it effecting the molecular structure of the steel? will the steel shims be able to handle the compression loads put on them after grinding without deforming at all? pretty hard to say isn't it when you have absolutely no idea what you are in fact doing to an extremely precise piece of metal. you can try it but i wouldn't put it in my bike. the refill kit is only like $15 and comes with 4 or 5 shims of 5 or 6 different sizes each. thats like a total of 25 or 30 shims in the small kit. the full kit spans 1.0 to 4.0. i have never touched any shims more than .5 away from 3.0 and thats including the 250, and several 600s which all use the 7.8mm japanese shims. IIRC oem shims from the factory are 3.0 and most of the time the valve system compresses which means you would usually be adding larger shims.

for something like valve train parts... drive train parts... bearings... things that have to work perfectly for the engine to work well... why try to save $10 risking something critical in your engine?

[Bigballsofpaint]

well i can tell you that right after grinding them they are cool to the touch, so the surface temp isnt getting hot enough to change the structure of the metal.

I only started the thread to see what people opinions were, its not like ill get rich off 2 dollar shims. We will be putting them back in the bike this week and i see no reason for it not to work.

Also after i did the shims it was just as precise as before grinding. .0002in is more than sufficient for me. Im not going to base if this is a viable option just on your opinion, i was just trying to help people out if there was a demand for it.

Your arguements are all valid, thats not why im here. I am also an engineer so i understand heat treating and hardness of metals.

[CynicalC]

Originally Posted by alex.s

just buy the 3.0 refill kit.

its a horrible idea to grind on the shims.

He works in a machine shop. He's using a surface grinder. I see no problem with this.

[Bigballsofpaint]

Originally Posted by CynicalC

He works in a machine shop. He's using a surface grinder. I see no problem with this.

Thanks, while im sure there are many other more qualified than myself. Ive been an operator and doing setups on 3 and 4 axis machines for 6 years, and ive been the programmer there for 4 years, they have paid for me to go to school and will continue to do so. As Racer X said as long as im not holding these and trying to use a little bench grinder then he felt i was OK too. This was my first time doing the shims and it worked out well, figured if anyone else needed some i could help. My boss is very generous about letting me use the machines and what not for my own personal things so long as it doesnt interfere with my work.

[CynicalC]

I think alex just didn't realize you were using a precision machine since you weren't really clear on that.

[Bigballsofpaint]

Thats true, i only typed the dimensions and tolerances i was getting off of the machine. Its a surface grinder with a magnetic table and good wheels, i looked closer at it when i was using it and it goes down in .0001 increments, i wont say its accurate to that, but its very close.

[alex.s]

if you have real machinery go for it... i thought you were going Casey style and grinding shims with a hand grinder. that guy really did that ****. and put that crap in other peoples bikes too.

just remember to get rid of the size markings on the shims if you modify them. otherwise you will confuse the hell out of somebody

[Bigballsofpaint]

i didnt even see a size marking, ill look at the ones i did before putting them in the bike tonight. And ya i agree using a hand grinder is just asking for trouble, no worries there

[alex.s]

i don't believe stock shims have markings but most of the aftermarket shims have them

[80MPHdownhill]

How do you know that the shims don't have a hardened surface?

If they do, you'd be grinding that surface off!

Seems like a fairly small amount of money to just buy the proper shim kit. The money isn't much, plus, this isn't a job you need to do every day.

[Bigballsofpaint]

If they are hardened it would be the entire shim was hardened steel (which it is). A small surface grind would not create enough heat to change the hardness of it, unless i was to take it all off in one cut very fast, or have a large amount to take off and use small cuts. But these shims only needed to be taken down .004-.005, which is nothing. So a few small cuts wouldnt cause enough heat for that.

But, we also have a hardness tester at work, so i suppose i could use that just to show, i would just need a shim or 2 donated since the only ones i have are going back in the back.

[alex.s]

Originally Posted by 80MPHdownhill

How do you know that the shims don't have a hardened surface?

If they do, you'd be grinding that surface off!

Seems like a fairly small amount of money to just buy the proper shim kit. The money isn't much, plus, this isn't a job you need to do every day.

its easy to **** it up if you don't know anything about metal or don't know what you are doing. if you have the proper equipment and know how to use it, there's no reason not to. well i mean you know aside from the obvious time when you have to go up in shim size instead of down. which unfortunately is kinda more than half the time... but alas, for the times when you go down in size, its fine... but again proper equipment means a $50k piece of precision machinery... not something most people have access to

[Bigballsofpaint]

The way im looking at it is the majority of people who own these bikes wont even have it long enough to need to do a valve a adjustment. Some will only do maybe 1 in their life. Why purchase a full shim kit if you dont have to? I know theres also those of us who plan on keeping it for a while, and while a shim kit would be nice, it may not be needed. If i can buy shims that people dont use, then i can use them and hopefully get an assortment of them. I wont be welding beads on shims to make them bigger, so like you said Alex.s the larger ones may be harder to get for me but its just a thought i was putting out there.

[80MPHdownhill]

Originally Posted by Bigballsofpaint

The way im looking at it is the majority of people who own these bikes wont even have it long enough to need to do a valve a adjustment. Some will only do maybe 1 in their life. Why purchase a full shim kit if you dont have to?

I agree, most probably will never need to do a valve adjustment during the time they own the bike, and the vast majority will only do 1.

I guess from that fact, though, I'd come to the opposite conclusion. For a "one time" thing, it doesn't make sense to me to grind down shims to try to save $35.

[alex.s]

... i've done 3 valve adjustments so far on my bike btw

[menikmati]

Originally Posted by alex.s

... i've done 3 valve adjustments so far on my bike btw

Mine needs one, pay you cash monies? $$$.

[Bigballsofpaint]

Originally Posted by 80MPHdownhill

I agree, most probably will never need to do a valve adjustment during the time they own the bike, and the vast majority will only do 1.

I guess from that fact, though, I'd come to the opposite conclusion. For a "one time" thing, it doesn't make sense to me to grind down shims to try to save $35.

To each their own in that regard, for me personally since i have access to everything, the bike only needed to be apart for a day since iw as able to do the shims at work. Instead of having to wait and order the correct ones, and i was able to save money. If your already doing the valve job yourself, chances are your doing it because you either like to tinker, or to save yourself money and not pay the dealer. Maybe someone would only need 1 shim, why order a kit when all you need is one? Many arguements can be made for and against it, i guess im not known nearly enough on this forum to really be trusted that much. Thats fine with me, just trying to help a little since this forum has helped me so much.

Alex.s, their arent too many people who are like you/us/etc. It makes sence for you to have a kit, from doing so many yourself or possibly helping others in your area who arent entirely confident in their own ability.

[80MPHdownhill]

Here's from a different forum. The below is supposedly from a Kawasaki manual. True or not? I don't know. But I'd not take even a 1% uncertainty to save $30.

Do not put shim stock under the shim. This may cause the shim to pop out at high rpm, causing extensive engine damage.
Do not grind the shim. This may cause it to fracture, causing extensive engine damage.

The shims are surface hardened, if you go grinding/sanding or whatever you do, you could go below that and have a piece of soft metal in a high wear place.

[alex.s]

that warning is because most people who read it don't have the proper machinery to do the job correctly. the entire shim is a piece of hardened steel. not just the surface. if it were just the surface that was hardened, the inner part of the shim would still compress. in other words there is no point hardening only part of a shim since the entire shim is put under stress. when you have quality machinery you can cut accurately (flat surface) as well as at the correct pace for the metal (with lube, not getting the metal too hot which would effect the hardening)

like has been said, if you are a machinist, its a no-brainer. if you aren't a machinist, its an impossibility.

[80MPHdownhill]

Originally Posted by alex.s

that warning is because most people who read it don't have the proper machinery to do the job correctly. the entire shim is a piece of hardened steel. not just the surface. if it were just the surface that was hardened, the inner part of the shim would still compress. in other words there is no point hardening only part of a shim since the entire shim is put under stress.

How do you know that for sure?

Many valve shims are only case hardened. That means only the surface is hardened.

How do you know whether Kawi 250 shim are case hardened, or something else? Do you have some specifics on the metallurgy of these particular shims?

I guess we'll have to agree to disagree, that's fine. But I'd leave anyone deciding whether to do this to their bike in order to save enough money to go to Subway a couple of times with this:



(1) Kawasaki OEM Service Manual....

QUOTE

CAUTION
DO NOT PUT SHIM STOCK UNDER THE SHIM.
THIS MAY CAUSE THE SHIM TO POP OUT AT HIGH RPM, CAUSING EXTENSIVE DAMAGE.
DO NOT GRIND THE SHIM.
THIS MAY CAUSE IT TO FRACTURE, CAUSING EXTENSIVE ENGINE DAMAGE.

v.

(2) Some dudes on the Internets . . .

"Yeah, go ahead and grind on your valve shims. You'll save $30."

[Bigballsofpaint]

Well if anyone has a couple shims they would like to donate, i would be more than happy to grind off .002in (.05mm) and do a hardness test before and after. We have a vickers machine in the shop that doesnt get much use.

[alex.s]

i have done ninja 250 valve jobs at least 10 different times... i have dozens of stock shims i can donate. pm me your address, jay and i'll put in some of the OEM ones, and a few of the aftermarket ones i have and mail it over. we can do some tests since i have so many extra in sizes nobody ever uses.

i did some extra reading. supposedly kawi (as with almost all OEMs) shims are through-hardened. many aftermarket shims are only case hardened. i've heard mixed stories of hotcams being both through hardened and case hardened so we will find out...

[SmithSwede]

Jay, thanks for the offer. To answer your original question, I would be interested. Not sure why you are getting so much static. If people think a ground shim will blow up their Ninjas, kill the family dog, and cause male pattern balding, then don't get them. Personally, I'll follow the data and take my chances.

[Bigballsofpaint]

I dont mind the static, they are legitimate questions and it seems ive at least shown its being done the correct way.

The owners manual is going to cover its own ass and put dont grind the shims for obvious reasons, but theres a lot of things the owners manual says not to do that get done. How many people here actually follow the correct break in procedure, and how many people do their own work when it says to have a certified technician to do the work?

Alex.s is helping me out and i appreciate it, he will be mailing me an assortment of shims, both OEM and the aftermarket shims. I will do the test on 8 shims, 4 OEM, 4 aftermarket. Ill take 2 initial hardness readings of each shim, then ill grind .002in (.05mm) off 2 OEM and 2 aftermarket then take the hardness reading in 2 spots of each one. Then ill grind .005in (.125mm) off the remaining 2 OEM and 2 aftermarket ones and take readings again. Im going to try to buy enough shims so that if i even have to grind the shims i would not have to remove more than .002 in from them.

I may not have to do any grinding though. Im going to start by buying peoples shims hopefully, then i could at least do exchanges. If i dont have the right size then i would do the grinding.

I will update this thread when i get the results, (end of next week) if everything checks out then ill make a thread in the F/S section unless Alex would rather something else.

[SmithSwede]

Thanks Jay. Please do post a follow-up. I think it would also be very interesting if you obtained very accurate measurements of the ground shim prior to installation, and then measure the same shim after however many thousands of miles it been in the engine. Would not surprise me that the shim experiences no wear at all.

[Dragone]

supposedly kawi (as with almost all OEMs) shims are through-hardened. many aftermarket shims are only case hardened. i've heard mixed stories of hotcams being both through hardened and case hardened so we will find out

I too am curious to this one. Such a small shim to not be thoroughly heat treated/quenched and then be ground on the surface grinder.