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Stainless race valves

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I am thinking of having a batch of stainless valves made for these. I can do slight oversize if you want. If interested give me a yell. Need to know if best to make a small batch or big batch. These are under cut stem and swirl polished

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I would be interested in 2 sets. 1mm over on the Intake only.

Will they be "flat faced" for more compression or "dished" to save weight?

How about using a 15degree "back cut" behind the 45degree sealing face to increase airflow at low to medium valve lifts?

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Will look at blanks. Can do either way most likely. Flat face is good as weight is not a big issue and undercut takes some off anyway. Motor responds better to a 30 degree backcut and most bike valves will not do a 15 degree because tulip angle is usually in 20-26 range to start with. 1mm oversize intake it is.

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Chuck, these are for CRF150/230's   Could always do something special for XR200 as only 31 OS available and 25 standard exhaust. If running a BIG cam oversize takes some work if you bump both sides.

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Dreams do come true. I also would like 2 sets for the crf230f, so ad that to your order. Myself would perfer flat faced valve's do to a couple of reason's. First a flat face valve has less surface area then say one with a dish. Less surface area the less heat that can be absorbed thru the valve, which could be good or bad dependen't on intended application. For an air cooled engine, i would think you would like to get the majority of heat out through the exhaust which most heat goes out the engine's exhaust any way. No coolant jacket to help with cooling with air cooled engine, so keeping valves cool and happy the better. The exhaust valve is one of the most punished parts in an engine, just shy of glowing red during heavy loads if not red and ready to melt. Sure a flat faced valve may be heavier but you mentioned uder cut stems, awesome weight savings there plus the possibility of more flow thru the  port and valve. More compression is on the table also with flat faced valves, life is getting better already. Who do i make the check out to.

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Dreams do come true. I also would like 2 sets for the crf230f, so ad that to your order. Myself would perfer flat faced valve's do to a couple of reason's. First a flat face valve has less surface area then say one with a dish. Less surface area the less heat that can be absorbed thru the valve, which could be good or bad dependen't on intended application. For an air cooled engine, i would think you would like to get the majority of heat out through the exhaust which most heat goes out the engine's exhaust any way. No coolant jacket to help with cooling with air cooled engine, so keeping valves cool and happy the better. The exhaust valve is one of the most punished parts in an engine, just shy of glowing red during heavy loads if not red and ready to melt. Sure a flat faced valve may be heavier but you mentioned uder cut stems, awesome weight savings there plus the possibility of more flow thru the port and valve. More compression is on the table also with flat faced valves, life is getting better already. Who do i make the check out to.

Pm TeamRude (Terry Miller)

"Millers Vintage Cycles"

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Valves are going to be done in couple weeks. Stainless undercut, flat top. He is making oversize intake. If wanted a set in stock size please tell me now so he can make a few sets. If anybody is interested PM me and I can get you in touch with supplier. Only making 10 sets right now.

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Hey they just got here. Very nice valves. 1.2mm bigger intake, flat faced and undercut and swirl polished.. He made a batch of 12 sets and I grabbed half of them for jobs. Get them while you can. This is same guy who makes me custom valves for other motors. great stuff and decent prices.

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Yip, yip, Yippie!

All bikes are running well right now....

Extra engine on the bench has been begging me for upgrades and feeling neglected....lol

Getting Ready to start on some machine work soon... (Sleeve, bore, shortened valve guides, oversize valves, porting) and a Web MC-2 cam

(for an ultra wide, progressive power band.)

While it's down and being whittled on, got to send off crank to Powroll for a 4mm stroker.

Edited by adnohguy

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