Did my first ever valve check, got a few questions..

So I checked my valves for the first time today, it was definatly the biggest job I've ever done on a bike but it went well. On the intake I read L: 0.004in, I can jamm an .005 but its tight. R: I can't even fit a .0015in.

My first question is what do I use in the shim equation if I can't get a right side reading? SHould I get a different set of feeler gauges?

On the exhausts I'm really confused, it's hard to decide what to call it, I can jam a .012 in in both sides but it is very tight. .011 is pretty snug too but not near as bad as .012 any lower than .011 and it is hard to really say one is a lot easier than the other but obviously it gets incrementally easier, it is just less noticeable. Should I just call them both a .011 even though it is pretty snug? Should I maybe go for .010?

If that is too much reading for any one I have intake L: .004in R: can't even fit .0015 exhaust: both .011 which is snug.

I really wish I had given the crank a turn to make sure I was on the right stroke but my manual said check for play on the rocker arm and there was play so I just went with it but now I'm wishing I tried giving it a turnt to see if there would be even more play. My lobes were facing the back of the bike if that gives an indication. ( I thought I had read that it did)

If my shims have the number worn off of them, what can I use to measure them?

Do I have to use this tool: http://www.canadiantire.ca/AST/browse/6/Tools/MeasuringTools/SpecialtyMeasuring/PRD~0581200P/Mastercraft%252BMicrometer.jsp?locale=en

Or could I use this: http://www.canadiantire.ca/AST/browse/6/Tools/MeasuringTools/SpecialtyMeasuring/PRD~0586800P/Mastercraft%252BDigital%252BCaliper.jsp?locale=en

Finally, where can I order a proper shim kit? (Figure I might as well since delears are at least an hour away)

P.S. I'd like to add for anyone who is planning a valve check and is going by the CRFs only guide, when reinstalling the cam cover remove the rubber seal for the spark plug and fit it onto the spark plug tower, it is much easier than trying to place the cover on with the seal in the cover. (Found this tip in my manual)

Thanks for any advice!

Edited by DrDuke

I've never used the numbers on the shims. Use a micrometer to measure the shim, and if you need more clearance, use a shim that is thinner.

You really will benefit from buying a hot cams shim kit to adjust the valves, since every size is in front of you.

Intake clearances of .005 are perfect, Exhaust of .009 are ok, and at .012, you're still fine.

That tight right intake is a problem. I would replace the shim that is in there with one that is .006 thinner, and re-measure.

Right intake is always the first to go. Like the other guy said, you want one that's about .006" thinnerer than what you are taking out, but you need to check after you've replace to make sure. Use a micrometer or precise caliper to determine how thick the shims are.

You can buy a Hot Shims kit. Or, Rocky Mountain sells individual shims for about $1.50. They are sold in .05mm increments which equates to .002" increments. Do a Google search for "convert inches to mm" and you find many sites that will do the conversion. That will help you figure out which shim to buy. Better yet, buy two or three. One .006" smaller, another .008", and maybe one .01" smaller.

To replace the shim, you've got to take the cam out, but it's just a little more difficult than checking the valves.

So I checked my valves for the first time today, it was definatly the biggest job I've ever done on a bike but it went well. On the intake I read L: 0.004in, I can jamm an .005 but its tight. R: I can't even fit a .0015in.

My first question is what do I use in the shim equation if I can't get a right side reading? SHould I get a different set of feeler gauges?

On the exhausts I'm really confused, it's hard to decide what to call it, I can jam a .012 in in both sides but it is very tight. .011 is pretty snug too but not near as bad as .012 any lower than .011 and it is hard to really say one is a lot easier than the other but obviously it gets incrementally easier, it is just less noticeable. Should I just call them both a .011 even though it is pretty snug? Should I maybe go for .010?

If that is too much reading for any one I have intake L: .004in R: can't even fit .0015 exhaust: both .011 which is snug.

I really wish I had given the crank a turn to make sure I was on the right stroke but my manual said check for play on the rocker arm and there was play so I just went with it but now I'm wishing I tried giving it a turnt to see if there would be even more play. My lobes were facing the back of the bike if that gives an indication. ( I thought I had read that it did)

If my shims have the number worn off of them, what can I use to measure them?

Do I have to use this tool: http://www.canadiantire.ca/AST/browse/6/Tools/MeasuringTools/SpecialtyMeasuring/PRD~0581200P/Mastercraft%252BMicrometer.jsp?locale=en

Or could I use this: http://www.canadiantire.ca/AST/browse/6/Tools/MeasuringTools/SpecialtyMeasuring/PRD~0586800P/Mastercraft%252BDigital%252BCaliper.jsp?locale=en

Finally, where can I order a proper shim kit? (Figure I might as well since delears are at least an hour away)

P.S. I'd like to add for anyone who is planning a valve check and is going by the CRFs only guide, when reinstalling the cam cover remove the rubber seal for the spark plug and fit it onto the spark plug tower, it is much easier than trying to place the cover on with the seal in the cover. (Found this tip in my manual)

Thanks for any advice!

If you can fit the feeler gauge in, then that is the measurement. Don't get crazy with forcing the feelers in, but as a general rule, if it fits, that's the gap. If you can fit a 0.005 in the intake, then the measurement is 0.005. 0.004 is recommended if possible but not a 100% must.

On the exhausts, you will be fine with anything between 0.010 and 0.012. I have read that you can even go down as low as 0.009 if you want to, but I personally would target 0.010 and stay within the recommended spec.

As you can see, I have recommended that you adjust your valves to the low end of the spec. The less gap you have, the less acceleration in the valves themselves which will in theory, will give you more longevity of valve life. Less gap = less acceleration = less impact on the valve seats.

If your intake has closed up, which it sounds like it has...you will need to put in a shim smaller than the one that is in there...several sizes smaller. Then measure the clearance again and see where you are. You have to have some gap for the calculator to work properly.

It never hurts to give the crank a turn and verify your measurements before you start to shim. It's just good practice to make sure that you have everything lined up at top dead center (TDC) and double check yourself if need be.

Any digital or analog micrometers or calipers will do. Harbor Freight has a cheap set or you can but a more expensive set.

Ebay has the Hotcams shim kit for around $65-$70. That's where I got mine but you find them many places.

One more thing...if your intake did close up for the first time, you will need a valve job soon. Your shimming will last you maybe 8-10 hrs of ride time at most. After shimming again, it will be half of that. So save your money and plan to send your head for kibblewhite stainless steel valves. Or look into buying a prebuilt 2007 250R head built with Kibblewhite SS valves. I suggest AS Racing if you want it done right. Paul is great to work with and I wouldn't trust anyone else with it. Good luck and let us know if you need any help.

I ordered the hot cams shim kit, it's on Ebay cheap from the states but that'd take 2 weeks to get to Canada so I ordered it through a dealer about an hour away, cost me 107 + tax...Bastards. Atleast then I should get the shims next week though. I'm confidant I can take the cam out and put the shims in myself. (Fingers crossed)

I hope I can get more hours than that on this shim, I trail ride not race and I lug down low and short shift. Maybe I'll be one of those people who's valves last really long? I hope so anyway.

How much would I be looking at to have AS racing redo my head with Kibblewhite SS valves? How much for the 07' prebuilt head?

EDIT: Just spoke to Kim (Or some name like that) on the phone from AS racing and got some ball park quotes:

Fixing my head: 385 + taxes and shipping With this job they typically replace intakes with kibbles and just clean up exhausts

New head: 700$

The prices were approximate and I'm calling again tomorrow to get some more accurate quotes.

I'm just adding this info for anyone else who may be looking for the same info I am.

She said shipping would take 5-7 days. If I heard right this is for it to get to them and return to me which is amazingly fast. Usually it takes 2 weeks for something to get to me from the states. And that is just when I order stuff online, immagine if I had to send it first! 4 weeks without a bike!

I was also thinking of replacing the valves myself and just sending the head to have the seats cut, but I wouldn't know where to send it. Any good tutorials for this job? I'm having a hard time finding much.

there is a tutorial at AS racings site. They have tutorials on checking valves and also removing the head for shipping.

Please keep in mind that if I have to send my head away I'll be sending it from Ontario Canada just incase any shops do not do international work if they are outside Canada.

Edited by DrDuke
Took out link because it doesn't show up.
I ordered the hot cams shim kit, it's on Ebay cheap from the states but that'd take 2 weeks to get to Canada so I ordered it through a dealer about an hour away, cost me 107 + tax...Bastards. Atleast then I should get the shims next week though. I'm confidant I can take the cam out and put the shims in myself. (Fingers crossed)

I hope I can get more hours than that on this shim, I trail ride not race and I lug down low and short shift. Maybe I'll be one of those people who's valves last really long? I hope so anyway.

How much would I be looking at to have AS racing redo my head with Kibblewhite SS valves? How much for the 07' prebuilt head?

I was also thinking of replacing the valves myself and just sending the head to have the seats cut, but I wouldn't know where to send it. Any good tutorials for this job? I'm having a hard time finding much.

Please keep in mind that if I have to send my head away I'll be sending it from Ontario Canada just incase any shops do not do international work if they are outside Canada.

That's a lot of $$ That does suck.

I repeat, if your bike has been running fine and all of a sudden, the intake has closed up, and you are now shimming it for the first time, then your valve shimming will last 8-10 hrs max. If your valves go to zero again and you shim it, then you will get half of that life and so on. After about 3 shims you are running the risk of seat damage if you continue to shim and you will also get to a point where there are no shims in the kit small enough to shim your valves. You can "hope" all you want, but this is fact. I'm telling you that this is the way it is.

A round about price is $450 or so for new valves and about $750-$800 for a higher hp 250R head. But, you can sell your old head on ebay for $150 or so to recoop some of your $$.

You need special tools to do the triple angle cut on your seats, to lap your valves and to install the valves. There are a lot of parts that need to be replaced (guides, etc). This is not something you want to do by yourself to save money. Send it out, let a pro like AS Racing do the work, and get back a head that will last you a long long time. I know that AS Racing does work for people all across the world and he won't screw you over on the price or the quality.

The bike was running well and it wasn't a really noticeable change but it did get harder to start. (It was cold out when I noticed this) As it has warmed up from 0-5 degrees to now 15-20 degrees it has gotten easier to start again. Hell just after I checked the valves it started on the second kick.

What I have noticed is that I have to choke it longer for it to idle, if I stall it it can sometimes be a pain to start again, then sometimes it starts right up. I also noticed a bit of a power loss.

I bought the bike used, previous owners say the engine was never opened but who knows if they were lying. I guess I will find out when I shim it.

That sucks I can't do the work myself, but hey atleast when the head is off I can put a new piston in right? It's still a good learning experience.

You definitely want to put a new piston, rings and decompressor spring on when you do the top end.

A lot of people sell their bike when they need a valve job. Hopefully yours is not one of those. Post the measurements of the shims that you take out and we can tell if this is the first shim or not. The bike not wanting to start while warm is "the" key indicator of an intake valve closing up. Do you know how many hours are on the bike? Are the engine and the trans cover show wear of the gold paint? How much wear?

Lots of wear on the covers which I stupidly overlooked when I bought the bike. I was thinking about starting a thread about how indicative the engine and trans covers are of a bikes use. I see a lot of adds that say stuff like, "Seven hours use..." and the clutch cover is totally worn. Aside from that no idea really how many hours on the bike, the guy estimated 150.

It is most likely that the valves are gonna need to be done, judging by the clutch cover. I couldn't never bring myself to sell someone else my problem so obviously I'll be doing the work...At least it is a learning experience right? I just wish lessons were not so expensive.

I've been thinking that something is funky with my decompression as sometimes when I'm trying to start the bike with the E-start it will stop turning over wit a bit of a clunk or a weird "kisshh"...It's a hard sound to explain, maybe I should youtube it.

The girl from AS racing also mentioned that they could turn my X head into an R head...What did they mean by this? It sounded like they were saying a port and polish but I dunno. I thought the main thing about the R head is the R cam?

Live and learn...if it does have a 150 hrs on it, then a valves, piston, rings, cam chain, decompressor spring all need to be replaced just to be on the safe side. He probably knew that it was time and it was easier to unload than pay to fix. I know, I have a hard time selling junk too....but many others could care less.

The decompressor noise you talk about is strange...but perfectly normal. No worries. Mine has always done the same thing.

Yeah, they can port and polish a head to make it flow like and R head. That's all your call. Just remember, you can sell your old piston and head on ebay after you swap it all out. The R cam really gives a good power boost to the 250X. The different year cams have different characteristics. You can search on this if that's the way you want to go. Just another $175 new (ha!) or maybe you can find a cheap one used on ebay or on the message boards.

I'm going to look into buying an R head or cam. Is there any point in buying an R head or should I just get the R cam? I'm going to look up the different year characteristics because I want bottom end power.

I was hoping to buy a newer 250R (like 08) but it looks like if I'm gonna be dropping 1000 bucks into this bike, then getting the R will have to wait.

I'm going to look into buying an R head or cam. Is there any point in buying an R head or should I just get the R cam? I'm going to look up the different year characteristics because I want bottom end power.

You are contradicting yourself here Doc:ride:

What exactly do you wish to achieve, a compromise HAS to be made somewhere along the line:ride:

From what I've read thus far, an R cam will increase power throughout the whole RPM range, so I shouldn't have to worry about losing bottom end. (This was my main concern)

Now it seems I just need to choose where I want to gain the most power. 05' R cam seems to be the one that people on here have said increases the most bottom end, but it is lacking in top end. So I will probably go for the 05 because even if it does lack over rev in comaprison to other R cams, it should still increase over rev. over my X cam.

What I ment when I said I want bottom end is that I would like to increase bottom end, even if that means sacrificing top. I'm sick today and tired, so maybe thats why I'm having trouble understanding what you mean Scotty...Maybe I''ll have to re-read this when I'm in better shape.

I'm not sure who is saying that the 05R cam is lacking top end. It increases power throughout the range...combined with the pink wire mod, it really wakes up the bike.

It's funny you now that I think about it you were one of the threads I was reading arguing that the r cam would not decrease top end.

What I mention to say was that it has less over rev than r cams of other years. I'll put up the link when I go to my computer after auction hunters is over

Just got off the phone wit Ms. Smith and I've got some estimates to share:

07' R head with:

AS valves 679$

-These are valves that are lighter than kibbles, AS racing has started making them for their racers. In terms of reliability I'm not sure how they compare to kibbles.

Kibblewhites: 699$

Gotta keep in mind that these heads do not include cams. From AS I think she said the R cam was 225 or 250. One on Ebay is 175.

To redo my head is 385$ to port and polish it is 349$ This would make a combined total of 734. This head is supposed to be even better than the R head. If I send in my cam, they can shim my valves for free before sending it back. They would also look over things like the decompression and replace a decompression spring for a buck fifty.

To summarize:

R head: AS valves 679$ Kibbles: 699$

Redo my head: 385$

Port and polish: 349$

They can send me an R piston for 150$ including everything.

Head and base gaskets 32$

They offered a flywheel puller with one would need should I chose to replace my timing chain I'll need one for 28$.

What do you guys think I can get for my head? This is the main question because If I can't make a good deal of money back on my head then it really isn't worth it to buy an R head. There is an R head on ebay for 450 used with new valves.

hmmmm,im very interested in this as well because i am want to do a similar head job to my X this fall,though im strongly considering an athena 280 kit as well

I'm glad it's useful to someone else, thats the main reason I'm keeping the post updated with as much info as

I can. I'm really interested in a big bore kit as well, I think I would go with the thumper racing big bore kit just because it's what rickramsey chose. He mentions something about the oil squirter and how you would need to modify the cylinder if you installed a newer cylinder on an 04X. The Thumper kit includes this mod, I wonder if the athena does...I'm sure 10 more ccs would add some awesome grunt.

I can't wait to do some research on the big bore kits...I guess I'll throw whatever stuff I find into this thread as well...Whatever seems important and usefull.

If you can find someone to help you pull and re-install the head, this doesn't have to be too expensive.

New Kibblewhite intake valves are about $160 a set with springs.

Machine shop work to touch up the valve seats and probably even re-assemble the head-$60 to $80. You head is now nearly bulletproof.

New piston, rings, gaskets-$140

R cam-$50 used, $125 new.

Maybe $450 to make a great bike run for a long time.

So there turned out to be no work today and I decided to take the bike apart.

Left shim: 0.0785 in = 1.9939 mm

Right shim: 0.0779 = 1.97866 mm

The writing was mostly wore off but I could make out 195 on the right and 1 5 on the left. I guess these really were stock shims and I'm pretty happy about that. :smirk:

The only other thing I could wish for is some clearance on the right side..

One person on here mentioned to go .006 in smaller shim on the right and then check the valves again. That would mean .006 in = . 1524mm so RIS 1.97866 mm - .1524 = 1.82626 mm shim.

The closest shims would be 1.85 and 1.8, which should I try first? I've heard it is better to go with the smaller shim but if my clearance is 0 with a 1.97 and I go with 1.8 then my clearance would be .17mm but if I go 1.85 then my clearance should be .12mm, which is spec. When I think about it though, I probably have SOME clearance which might take a few mm off the .17

I just want some second opinions...Anyways I didn't want the bike to sit with the engine open so I put it all back together and it still runs :smirk:.

Edited by DrDuke

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