[JoeP]

I have an 06 749. I want to know if my cooling system is working properly. The bike runs fine for 1 hour or so, but then starts to run hot. It easily goes to 220 when stopped at a light for a just a minute and takes a while to cool down after running. The fans come on at the right temp (215). However, I don't think my water pump is working. When the bike is hot, I can't feel any pressure in the hoses that go into the water pump. Isn't the cooling system supposed to be pressurized?

 

[Craighjr]

The cooling system is pressurized from the heat build up in the system not the pump. I would try to swap the radiator cap first.

 

[Tuned]

With the engine cold, pull the coolant cap off and run the engine. Get it nice and hot to see if the coolant level changes. If it bubbles and swirls, then it's working properly. If it doesn't and the coolant simply vibrates in the radiator, then you could have a plug up somewhere. I like the idea of a bad radiator cap, the spring and rubber bits can fail over use.

 

[Aussie_Bob]

Does it use coolant ?

 

[JoeP]

Does it use coolant ?

If you mean "does it lose coolant" then no. I do notice that coolant boils out when the temp gets to 225, so I don't think the system is holding pressure. I'll try a new radiator cap.

Thanks, all.

 

[JoeP]

I'm looking for a replacement radiator cap. Any harm in going from the stock 16psi to 23psi? Or should I just go with the OEM part?

 

[Tuned]

Depends on what the stock is… I don't remember what the label said on the top.

 

[Warp Racer]

Get your cooling system flushed. My 999S radiator had a build up of loose, scale type deposits throughout it. My fuel pump shaft & impellor is in perfect condition. The filler neck of the radiator where the radiator cap main rubber seal seats was also corroded,. This issue didnt allow the cooling system to pressurise and ultimately letting coolant overflow due to heat expansion. Fix these, get your cooling system pressure tested for peace of mind and run a good quality coolant. I prefer using coolant that doesn't require mixing.

Edit: I meant to add that I bought a new radiator cap after the filler neck was repaired.

 

[Warp Racer]

I'm looking for a replacement radiator cap. Any harm in going from the stock 16psi to 23psi? Or should I just go with the OEM part?

Stick to the factory spec radiator cap, as it is designed by the factory to release system pressure onto your overflow tank at that specific pressure. Having a higher pressure cap fitted, though you may think it will be a great stop gap, you may actually cause more stress on your entire cooling system.
My 2 cents

 

[Warp Racer]

How corrosion and solidified coolant can damage a radiator cap.


Also make sure your order the correct cap. I ordered the modern version by accident and it will not fit