Hey guys, This question has been bugging me, mainly because I have found an abundance of time to ponder such things: looking at this parts fiche of the hrc coolant upgrade kit for the f4 and f4i how would the coolant circulate with the added radiator (item 5)? They plug up the normal input frm the water pump and the output to the radiator (item 11). They also remove the input for the siphon tube and reserve tank, so is it safe to assume that you dont use a reserve tank on a race bike? Please humor me with a response as this is more for educational sake than a desire to do anything to the bike.

here is the photos origenal site with a parts list
https://www.slipstreamperformance.co...?cPath=1_17_64

HRC Parts


OEM Parts


Thanks, Chris.

 

I don't think that the drawings are detailed enough to make that determination. Not just based on those two drawings. See if they have installation documentation. That may make it more clear.

 

That kit is an oil cooler kit. It does nothing for the cooling system. It might even make it run hotter trying to cool the oil.

 

demon, so what your saying is they remove cooling the oil via the coolant all together and have the oil run through its own radiator, am I understanding you right? And it make it hotter because the oil would need air flow over it to stay cool, right? If so thanks! It seems obvious now, with the title and all.

 

That system sends the oil through a air cooler. Depending on where it's located, it could block some air flow to the coolant radiator. I'm sure HRC worked all that out though.

 

It sits below the radiator but from what I've heard it actually keeps the bike too cold and doesn't let it get up to temp when moving; but I can find hardly any info on it other than what I hear.

 

Keeps the bike too cold? Does it cool the oil too much?

 

If the bike doesn't warm to the proper operating range the tolerances are too tight
and can cause excess wear.

At least that's my understanding of the way modern engines are design/engineered.

Ern

 

The way they designed to coolant loop, the coolant that cools the oil runs back to the radiator but on the same side as the previously cooled coolant, to help warm the bike up to operating temp. The thermostat does the same thing it sends warm coolant back to the water pump until the bike starts to heat up too much than it opens and lets water pass to, and through, the radiator. I talked to my friend who knows way more about bikes and used to work as a mechanic on a team said "when they combined a bigger radiator with the oil cooler they would have to tape up the radiator restricting air flow otherwise they ran the possibility of cold locking the engine." He also said on every bike they used they bypassed the thermostat and just payed close attention to the temps and taped the radiator.

Edit: He also said that after awhile, on the newer bikes, they started to just modify the OEM ones so the coolant from the oil when in on the "hot side of the radiator, bypassed the thermostat and that was a lot easier to control.