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Only $10 for all 2026 SX, MX, and SMX series.
I appreciate the advice.
You must have the seats cut before installing new valves, otherwise your new valves will wear out prematurely.
Seat cutting is an art on these small stem dia heads. Has to be done by someone who really knows what they're doing...no hand cutters here.. concentricity must be .001" or under.
You were recommended by several on Thumpertalk, and if I had the extra $$$$ I would have had you do the work for me (In fact, I will the next time I do the valves...I'll be going with steel next time, and I want to get them done perfect next time).
I had them done by a local dealer, and they said they did just that (cut the seats). Is a dealer going to be as precise as you would be? Probably not...but I got the entire thing done for $150 labor plus parts (I have a friend at the dealership)...$$$ is a bit tight right now, and so I had to go economy over quality this time around.
Thanks for the advice.
The Shop
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I never said valves would melt or coolant would boil without heat. I am saying that you don't need excessive exhaust temps to get coolant to boil (ever hear of a bad radiator cap?), and you don't need coolant to boil first before valves melt; you float exhaust valves and they don't cool by seating, you'll burn them long before you see high coolant temps.
Shit, you can melt lots of stuff.
On the flip side, you can be towing with relatively low exhaust temps and be boiling over from lack of airflow, hot ambient temps etc.
You can overheat anything without airflow just idling eventually.
At idle, a engines exhaust temp is relatively cold compared to WFO, but with no water circulation, or the water not circulating fast enough you can have problems.
Too fast can be a problem too.
I've got an older 4-banger to put together here some day, gives a re-newed appreciation for my 2 strokes.
Yes, you can melt things without overheating the coolant. I said that in other posts within this thread. I once worked on a 3406B (Cat engine) that had injection timing problems so bad that most of the burn was happening in the exhaust manifold. The coolant temp was low, the pyro temp was sky high, and the thing melted its own turbo.
Again...proper coolant temp does help proper fuel burn, if all other things are set up and running properly.
Hard? Easy?
Playin Jesse... what do you have for a seat cutter? Serdi?
Pit Row
You can also run a higher pressure radiator cap to deal with cooling issues. I just put a 1.8 Kawasaki mini bike radiator cap on the 2009 YZ250F I just finished.
Slower riding, you could be right with inadequate airflow. How slow are you?
If you think dirt is bypassing the filter, look at the carb intake bell. If it is, it's evident.
Boiling point in a closed system must be the same in all altitudes,
what diferent is enginice against red line water wetter?
Titanium valves is lighter and moore heat resistant than stainless.
Wish I had a better picture but ......Factory Monster Kawasaki (Supermoto) assisted on the R&D of this product.
As for how slow I ride...it's all relative I guess...but on single track I very seldom get it out of 3rd gear...and most of the time is spent in either 2nd or 1st...so in relation to how fast I'd be going on an MX track (which is what this bike is built for) I'm going pretty damn slow.
And the titanium valves are lighter than stainless, but stainless valves don't have the hard coating (nitrate, I think it's called) to wear off...and thus last longer.
Are you really getting hot enough to puke out fluid?
Maybe you have a leaky head gasket, that will boil the coolant and make it blow past the pressure cap real fast.
Instead of a 1.1 pressure cap get a 1.3 or 1.6 or whatever if its available if you need a higher boil point than a 50/50 mix gives.
If you need cooling, reality is, less coolant and more water cools better.
Coolant really isnt coolant, its a boil point raiser/freeze point reducer.
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