Feeler Gauge for valve check

[Peanuts]

Originally Posted by geometrician

I've taken out shims on customer bikes (esp the 250, 350, 400, 450, 500, 530, 690 engines metioned above) with such a depression hammered into them from the top of the valve stem they are unusable.

Me too. Makes it an extra pain to reshim as the clearance with the dimpled shim is artificially large.

I have seen the top of the valve stem bruised so much that the edge had to be ground to allow it to pass through the valve guide.

[Peanuts]

Back on topic...

Using 2 blades on top of each other is sometimes better than just one thick blade as the combination will flex easier around the cam/bucket area. If you use just one thick blade you can be tricked into interpretting the force required to flex the blade as a tight sliding fit.

I know cos I did it last night! Using a friends straight blades that I did not want to bend....

[geometrician]

Originally Posted by markjenn

Do you have any kind of reference from a mfg or other authority?

I'm just surprised by how little hard information there is on this subject.

- Mark

Every shim kit currently for sale lists hardening in the description

Here's a post from a machinists forum I just looked up

As from manufacturer/authority, yes. I've gone to Tech training courses provided by motorcycle manufacturers, apprenticed @ MegaCycle Cams, worked at a shop where we prototyped & repaired cylinder head/valve systems for manufacturers, and have been reading the publications of machinists journals & trade industry newsletters for years. And that's just me. The people I ride with & talk to work for NWI, DARPA, JPL as well as a gear maker from Switzerland whose company provides the machinery for Toyota & GM among others to grind & harden all their transmission gears.

There is no fight. Just trying to keep mis-information from becoming "internet fact". This forum above all others is (to me) full of the right spirit. When there's something I actually know about I'll contribute- otherwise I read what others are saying & try to pick up the right info from it. As a high-mileage KLR owner I can tell you I don't waste my time on any of the forums dedicated to that bike- too many idiots; too confrontational. If KLR forums are bad, try something gun-related. Too much ego over information.

Long Live Orange Crush

Originally Posted by Peanuts

Using 2 blades on top of each other is sometimes better than just one thick blade as the combination will flex easier around the cam/bucket area. If you use just one thick blade you can be tricked into interpretting the force required to flex the blade as a tight sliding fit.

To be sure you come up with more precise measurements by adding blades, that's why buying a quality set with all the low numbers covered is best. Right now Snap-Ons best set is $13.45 retail and contains 35 blades.

Not sure what you mean about bend/flex? I always feel the tension on the blade(s) as I remove them from the gap, not pushing the blade(s) into it.

Originally Posted by Peanuts

I have seen the top of the valve stem bruised so much that the edge had to be ground to allow it to pass through the valve guide.

Ha Ha yeah with some of the modern heads it's hard to get in there to do that job. People who don't work on them for a living don't get to see all the crazy stuff people "do" to their bikes. At the shop & at the home garage I have a "Hall Of Shame" of failed parts that I keep on display to encourage discussion

[markjenn]

Originally Posted by geometrician

As from manufacturer/authority, yes. I've gone to Tech training courses provided by motorcycle manufacturers, apprenticed @ MegaCycle Cams, worked at a shop where we prototyped & repaired cylinder head/valve systems for manufacturers, and have been reading the publications of machinists journals & trade industry newsletters for years. And that's just me. The people I ride with & talk to work for NWI, DARPA, JPL as well as a gear maker from Switzerland whose company provides the machinery for Toyota & GM among others to grind & harden all their transmission gears.

All well and good, but when the day is done, all you're doing is what I've seen tens of others do on forums of all sorts - say "they know" but can't quote an authoritative source.

- Mark

[triplenickel]

Originally Posted by markjenn

All well and good, but when the day is done, all you're doing is what I've seen tens of others do on forums of all sorts - say "they know" but can't quote an authoritative source.

- Mark

Ummm that's kinda what forums are all about, have you considered taking the initiative to contact manufacturers yourself? Otherwise you'll probably just question whether someone else did even if they claim to have. Get some literature for us all to see.

[markjenn]

Originally Posted by triplenickel

Ummm that's kinda what forums are all about, have you considered taking the initiative to contact manufacturers yourself? Otherwise you'll probably just question whether someone else did even if they claim to have. Get some literature for us all to see.

All I've said is that there is a lack of hard information. I don't claim to know the answers like some do.

- Mark

[triplenickel]

Originally Posted by markjenn

All I've said is that there is a lack of hard information. I don't claim to know the answers like some do.

- Mark

I understand what you were saying, I was suggesting if you weren't happy with the answers you got perhaps the source would be another choice.

[Peanuts]

Originally Posted by geometrician

Not sure what you mean about bend/flex? I always feel the tension on the blade(s) as I remove them from the gap, not pushing the blade(s) into it.

Because the laminate of gauges are more flexible than one gauge. They bend around the cam lobe easier and give a more accurate feel.

[Steveman]

Originally Posted by geometrician

I've taken out shims on customer bikes (esp the 250, 350, 400, 450, 500, 530, 690 engines metioned above) with such a depression hammered into them from the top of the valve stem they are unusable. They do, indeed, wear. .

This is 100% what I have experienced when talking about KTM engines with one overhead camshaft. No experience with the new designed dohc engine of the 350 yet, but for all others what you say is definitely right. I talked to so many smart guys telling me that shims dont wear but I personally have experienced the contrary.

I also can confirm, that with the config of KTM engines where no bucket is used and the rocker arm is in contact with the shim the engine speeds are the factor. While the valve clearence on bikes used from hobby riders almost keeps constant the valve clearance of bikes revved hard and used in competition needs to be corrected every 10 to 15 hours.
Thus I can say that two myths concering ohc engines with shims are wrong: valve clearance on ohc engines always changes in one direction (tighter) only - wrong. Ohc engines once broke in and re adjusted dont need valve checks as the clearance stays constant - also wrong.

regards
Steve