250-500cc urgent help needed please, WR300 seized

I've hoped someone else would talk temperatures. I have the Trailtech Vector with temperature sensor between the head and left radiator. I see the same warm-up as you GhostRider. My cruising temps are usually around 160 to 170, but as soon as I start climbing anything the temp always goes to 200 or so. If its slow and technical with a tailwind my temps have gone as high as 260 degrees. I usually try to shut down well before that, but only if I'm looking at my gauge and not the rocks. I put a little coolant catch bottle between my airbox and gas tank last ride and it helped keep my coolant level about 1cm above the fins in the radiator. Until now I've always had to fill back up.

I'm in northern Utah, riding between 6500' and 9000', temps vary a lot, 40:1 Amsoil Interceptor, 38mm Lectron, stock gearing, Rekluse. New Chinese radiators and silicone hoses (white!) with Bulletproof Designs guard/braces that I've had since new.

Went to Moab in April and forgot to put my E.E. skid plate back on after oil change. Was mad for forgetting but the engine ran much much cooler on that trip than it ever has. I don't think it ever got to 200 degrees. Ran more in the range of GhostRiders. I had just flushed the coolant system before that trip and thought I'd solved my heating problem but once the skid plate was back on it ran hot again. I think I'll take the skid plate off for the next ride and see if there is anything to that. Could the skid plate trap that much heat under the motor?

Long_Stroke, are you running conventional antifreeze or something like Engine Ice?

Regular anti-freeze. Been thinking about Evans.

Husky is finally fixed.

Will have to think twice next time I take my bike to dealer for repair. Head was installed backwards!!!

Yeah, how is the head backwards? I guess the motor wasn't in the bike, so they couldn't see that none of the radiator hoses, head stay, etc lined up?

Who did the work on your bike? That's a pretty unforgivable error...

yeah.. I was like WTF myself.. and even WTF!!! when I considered how much I paid..so when I called him, he was like.. sorry, just flip it around and retorque bolts.. no biggie.

I am not sure I should share the name of the dealer right now..

at least powerseal seem to do very nice job.

What is all that goo in your water ports? If that's grease it shouldn't need to be there.

too late... already put it all together.. btw, bike staterd first kick.. that's pretty nice for WR300

Wow, that's an elementary mistake at best. Anyone can plainly see the mismatch of the head to cyl regardless of head stay placement, which in itself is a dead giveaway.
It is advisable now to replace the head gasket for insurance due to you running the motor for a while and then removing the head.
I would name the dealer unless it was his 14yr old son that did the assembly. Glad you got it right, charge the dealer his rate for your time!

Head gasket is just an o-ring, I see no reason to replace it unless it is damaged.

No telling if it was pinched before hand, but Kyle has a point about if it works..

You can tell as they go flat or cut!
School boy error head on backwards, re skid plate could you put louvres in it to increase airflow but still have the protection?

I would totally share the name if i was you

going to start warming my bike up as slaven's suggests.

I always let it idle for 5min before a ride, and cringe when guys just hop on a 2 stroke as soon as its running. But I do tend to get quite a bit of spooge, couldn't figure it out as the bikes jetted near perfect.

Long straight away's even fully warmed up I tend to hit the kill switch once in a while to quench the motor. Dunno if it helps or not.

i ride them fairly quickly after starting, i just avoid putting a load on the motor till it heats up. no harm in letting it warm up tho. must be working ok for me as i have an insane amount of hours on the original topend on my nos 88 250.

this is not over yet ..

why would someone put double gasket on reeds? and lot of grease?? something is not right.. bike starts first kick, idles great and bottom and mid seem strong but it's lifeless on the top..