[KBkilla]

I have a 2012 R6 with 7K miles. After getting up to temp while riding, my radiator is reading 300* on the left side, but only 160* on the right side (side based on sitting on the bike). Is this normal, or is my radiator clogged up and not flowing properly? The reason I even tested it is because my bike seems to be running hotter than normal. It heats up quicker than it used to, and stays on the hotter side. The fans do work to bring the temp back down when the temp gets above 212* on the readout. It seems like before, it would only get above 200* on extremely hot days and riding in heavy traffic. I no longer street ride, and only ride on the track. I feel like I shouldn't be seeing 200* on the readout while on the track, even here in south Florida. I did have an issue before with corrosion build up in the system, because I accidentally left distilled water + water wetter sitting in it for too long. I thought I fixed this by running some of this Prestone Cooling System Cleaner through it, but maybe not. Maybe I should give it another shot, or should I just replace the radiator?

 

[Ruhe52]

I would think something is imped unrestricted flow of whatever you have in there. R6 with the hard pipe in the mix has a problem with crud and corrosion in those at time. Don’t know year or how you maintain. I would check thermostat one to make sure it is t frozen partially sbut. Then look in that long hard pipe on the left or riders left side if one of the 06- bikes for sure. I have seen those pretty restrictive because of corrosion. That said never tested one side of radiator temp vs other. When I find that stuff on a bike running hot. It gets replaced / fixed.

 

[KBkilla]

I would think something is imped unrestricted flow of whatever you have in there. R6 with the hard pipe in the mix has a problem with crud and corrosion in those at time. Don’t know year or how you maintain. I would check thermostat one to make sure it is t frozen partially sbut. Then look in that long hard pipe on the left or riders left side if one of the 06- bikes for sure. I have seen those pretty restrictive because of corrosion. That said never tested one side of radiator temp vs other. When I find that stuff on a bike running hot. It gets replaced / fixed.

I think I figured out that I had the heat gun setup wrong, and it was reading too high.
I've since corrected it, and now I'm getting more normal readings that are closer to the actual readings on the dash.
This didn't explain the huge delta in the temp readings on the different side though.

I decided to do a flush again anyways to see if that would fix it, and I think it did.
The readings on the left side are only 20-30* higher now versus being twice as high.

The problem now is that I think I have revealed a couple other issues.
Now that the right side gets up to temp properly, I'm noticing a tiny leak near the water pump.
Haven't quite figured out what it is yet, but going to start with replacing the simple stuff like gasket, washer, bolt, etc.

The Samco radiator hoses are over $300 now on STG
Hoping I don't have to spend the $ on those.

 

[KBkilla]

I think I found the source of the leak.

The gasket is splitting apart.

Ordering a replacement along with a new drain bolt/washer.

 

[Ruhe52]

See the corrosion on the outlet pipe on the water pump? Does the inside of the long hard pipe on left side of the bike that ultimately connects to left upper radiator look corroded. What about inside the pipe? If it is a mess you could have scale that flaked off and blocking a water passage or restricting flow. If you do go Samco make sure you buy the race version as it gets rid of all that crummy hard pipe Yamaha has in the cooling system. No idea why they continue to use that rubbish but worth a look.

 

[KBkilla]

See the corrosion on the outlet pipe on the water pump? Does the inside of the long hard pipe on left side of the bike that ultimately connects to left upper radiator look corroded. What about inside the pipe? If it is a mess you could have scale that flaked off and blocking a water passage or restricting flow. If you do go Samco make sure you buy the race version as it gets rid of all that crummy hard pipe Yamaha has in the cooling system. No idea why they continue to use that rubbish but worth a look.

Yea, I definitely had a problem with corrosion before. I accidentally left distilled water + water wetter for too long, and created a bunch of gunk.

I did one flush previously, and I thought it got it all cleaned out because I took all the tubes/hoses out and cleaned those up as well, and the water started coming out more clear.
I think there was still some parts of the radiator gunked up, and that's why I was getting a 2x higher reading on the heat gun on the left side than the right side.

I did pop off the left side hard pipe and inspected to make sure there were no blocks.

A really weird thing happened after I did the 2nd flush.
I went for a ride around my complex once up to about 140-150. It started climbing to like 170, and then randomly dropped back down to 160 instantly, all of a sudden. Then started climbing from there.
The only thing I can assume is it broke through all the gunk finally.
When I got back and started taking readings with the gun, they were more even than before.
That's when I started noticing the slow leak.

Fingers crossed the gasket peeling apart is the source of the leak.

 

[Ruhe52]

Probably not. You had an air gap in the cooling system would be my guess did you check fluid level again? Need to top off? Sometimes if you don’t burb it completely you can have the impeller housing for water pump with an air gap. what you might have seen was thermostat open displacing that air and then coolant then circulating the system. Just a guess but have seen that happen many times.