Engine coolant level

4 replies to this topic
  • geshields

Posted August 09, 2009 - 03:06 PM


This may be nit-picking but I have been adding about 6 tablespoons of Engine Ice to my bike to keep it toppped off after every day of riding. Does the level need to be full or should I not worry about it? It overflows everyday because of the Texas heat.

  • DeeCee

Posted August 09, 2009 - 06:27 PM


I assume you are topping it up so it is completely full and the amount you put in is the same each time.

If this is the case, what you are losing is due to the coolant heating up and expanding. The expanded coolant requires more space and gets forced out the overflow. This is normal. The radiator will always operate at a level which is below the top of the filler neck as it needs some space inside to allow for the expansion of the coolant when the engine gets up to operating temperature.

On my bike I have a catch bottle fitted (there are threads on this forum with lots of suggestions for such bottle). This catches the overflow, and when the radiator cools, it draws the overflow back into the radiator. The advantage of this set up is you not only retain your coolant, you also have some extra capacity in your system if the bike does overheat for some reason.

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  • 450licious

Posted August 11, 2009 - 09:06 PM


yeh the heat is good at sucking up the coolant, just make sure you dont sit in one spot idling for to long if the heat is eating it up. and definetely make sure you top it up whenever its low. even if you have a break halfway through your ride top it up if its not to hot to open.

  • grayracer513

Posted August 11, 2009 - 10:52 PM


If the radiator is filled to the top, it is normal for it to drop to just above the top of the tubes of the core. It should be stable at that level unless you over heat it, or the cap is faulty.

  • geshields

Posted August 12, 2009 - 06:35 AM


I always refill the radiator to the top and then it blows off to just over the fins inside. I will not top it off this weekend and see where it stabilizes. If it starts going below the fins, I will start to worry....

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