Coolant Issues???

I checked my coolant after a weekend of hard riding and it was a bit low ...maybe 1 1/2 inches low . Plus there was a bit of whitish goo on the lid. My oil looks fine and the coolant doesn't bubble when I rev it when its cold. Si I don't think its the head gasket. I topped it up and went for a ride today and it seems OK. Though I'm paranoid and could smell that sweet antifreeze smell but not out of the exhaust. I noticed the reservoir is full up now. I'm not sure if it had boiled over the first time before I topped it up and now its over filled and dripping out the reservoir overflow???The weather's been pretty cool so ??? I'm using Motul motocool premix coolant. I'm not sure if its got additives that would explain the goo. Please almighty Yamaha God ...don't let it be the head gasket.

2008 WRR
1600 kms
No mods.....yet

Keep an eye on the coolant level in the radiator and also in the plastic reservoir.
If the reservoir level keeps going up, then there's not much of a question about it.

Whitish goo is oil. If there's a slight pinhole anywhere, it'll definitely get worse. Oil pressure is higher than the water pressure, so that would push oil into the water if it was a head gasket. Maybe a hairline crack on the head? I'm just poking here. Might be some blowing out the tailpipe even if its a small amount.; keep an eye on it.

I'm not sure on the oil/coolant pressures on bikes but on cars the blown head gaskets I've seen have the goo on the oil cap not the rad cap. Depending where the seal is broken you can get a substantial positive pressure coming out when you remove the oil cap. ??? I'm going for a ride this morning. Hopefully nothing changes . And Shewolf- I don't think you should be using the "C" word in this forum...........you know......... Cracked head. Ha Ha

I've experienced it on a truck as well as a heavy diesel truck, that's why I mentioned it. We've seen this kind of thing in the truck shops back when the old Detroit diesels were still being used fairly often when they dropped liners.

As for the C word...well...call it Comic relief.

Well, went for a ride and no new goo. The rad level is down a bit and the reservoir level is up about the same ...1/2 - 3/4 inch. The oil level hasn't changes and looks fine. Shouldn't the coolant just suck back into the rad when it cools???

It should. I know mine equalizes when it cools off.

you could do a compression check.

i hope its not a HG or crack man, hopefully just some weird goo in your rad for some reason.

good luck!

If the level in the coolant reservoir keeps going up but never gets sucked back into the radiator when the bike cools down, that's not a good sign.

When I had my 2009 Suzuki DR-Z400SM with a 440 big bore kit, I found out the hard way that you had to coat the big bore kit head gasket with spray-on gasket sealer before you installed the gasket, or else you'd get a head gasket leak.
The leak made the bike's cooling system do exactly what you're describing:
The coolant keeps getting pushed into the reservoir but won't return to the radiator after the bike cools.

On my DR-Z, the reason for this was because the leaking head gasket had combustion pressure leaking into the cooling system and pressurizing it.
Even after the bike cooled down, the cooling system was still pressurized to the point that the coolant couldn't be sucked back into the radiator.
So, the reservoir level just kept increasing with no end in sight.

Naturally, I can't say for sure this is your problem, but it sounds like it.
It sure ain't supposed to be dropping coolant level in the radiator after just one ride.
Maybe try a new OEM radiator cap because it's easy.

Well. I took my WR to the local Yami shop to see the doctor. The mechanics ran a few test along with the Yamaha rep/mechanic who happen to be at the shop. They did a pressure test on the rad system and checked the rad cap- both OK. They also flushed and filled the rad then ran the bike at full operating temperature for a while. They then tested the coolant for CO2. Sounds like the test is reasonably sensitive to CO2 but the test was negative. Oil was fine. The only thing they came up with is that it could be a super tiny leak in the head gasket that only is a problem when you give 'er good for a while rather than the 10 minute road warm up they. I don't abuse it (I've only hit the rev limiter a couple of times) but I do mostly dirt with fast trails and hill climbs etc. I don't really feel like spending $4-500 to see if its maybe the gasket. I'll try riding it for a while and see if the problem miraculously goes away.