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Best valve seat material!?

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What's the best valve seat material to use with kw ss valves

Beryllium if you can find a shop that uses it

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Why do you want to run SS valves?

SS valves last A LOT longer than the problematic Ti valves with a negligable effect on performance.

Ronix, i think the seat material was hardened in 05 which works well with the SS valves, in 07 or 08 they went to a softer seat and thicker valve stem which was better for the Ti valves. after that i switched brands so am not sure what composition they use now. I would imagine that berillium seats would get pounded by the SS valves though.

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Ti on Beryllium lasts a lot longer than the factory setup, and as far as I'm concerned, these little motors need every advantage they can get. To run the steel valves properly, you also need springs, or you can experience valve float at max RPM. For me, it's a track bike, so more cost + decreased performance = not a good value.

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SS valves last A LOT longer than the problematic Ti valves with a negligable effect on performance.

Ronix, i think the seat material was hardened in 05 which works well with the SS valves, in 07 or 08 they went to a softer seat and thicker valve stem which was better for the Ti valves. after that i switched brands so am not sure what composition they use now. I would imagine that berillium seats would get pounded by the SS valves though.

BeCu is a catch 22 on SS valves. The BeCu won't chip like the iron seats, but will "sink" in head sooner.

SS valves are fine if you don't ride over 10K RPM. But they aren't the answer for the majority of the riders.

The reason the stock valves get a bad rap is you need to get the seats cut correctly. Honda's are notorious for the stock seats to move after 1 hour of heat cycles. That, and dirt.

The stock valves are good, nothing wrong with them. With a proper prepped head, you will get minimum 35hrs... most of the time 40hrs on stock valves for a good fast rider.

Most of you won't think this is acceptable... but these are race motors, not trail bikes.

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well i think it would be nice if RONIX elaborated on his situation, on why he's choosing SS valves. so instead of assuming he's a pro and needs every tiny bit of advantage he can get, im pretty sure he's inquiring about the SS valves for durability reasons. if im right, then USE THEM! i have and they outlasted the stock Ti valves three fold on the stock seats!!!

as for the valves, its right to say that the seats need to be properly cut to help valve life since the REAL problem is a combination of things:

-the valve seats must be cut properly and mated to the valves not only for a proper seal, but also for COOLING! mechanical parts WEAR faster when heated, so sufficient surface area for the heat to conduct AWAY from the valves and into the head keeps the valves temperature in check. worn seats decrease this "heat transfer" area allowing for less of the heat to be conducted away from the valve: increasing its temperature and accelerating wear.

-The Ti valves material is NOT homogeneous. Ti valves are surface hardened, new valves will last fairly long before the first shim. but once the hardened material wears away, the softer internal structure wears faster causing decreased shim intervals. softer valve seats help alleviate this problem since they will wear more WITH the valve: hence the change in seat material on the 08.

-The combination of Be (Beryllium) and Cu (Copper) is a good match with the Ti valves because Be provides low thermal expansion (keeps its shape) as well as superb heat conduction, and Cu softens the composition as well as being also an excellent thermal conductor, keeping the valves cool and giving them a softer contact surface. and i also agree that this material composition is less likely to chip or crack.

a stainless valves material is homogeneous (thus it basically wears at a constant rate) so shimming will be at more consistent intervals. secondly, kingmooch, last time i checked SS valves WITH springs are cheaper than a pair of Ti valves. and finally my experience with the SS valves produced very little difference in performance (none that i couldn't compensate for)...

Edited by funkinalive
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