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Hi guys, happy to be here. this is my first post on this forum. So I own a R1 14b 2009. Recently I replaced the starter motor and had to empty the cooling system. So today decide to flush and fill it back. At the end looking in the manufacture specifications it says should go in 2.73 l of coolant in the radiator including all routes and 0.25 in the coolant reservoir. In my bike all together went only 2 l. Is this an issue? Have I done something wrong when empty the system and flush it?or maybe when fitted back the thermostat? If anyone knows please share it with me. I used motul motocool factory line organic if relevant. Thanks

I don't know about the 14b specifically but my 4xv is the same. There is usually some coolant left in the engine and radiator after you empty through the drain plug.

When you refill, leave the radiator cap off until the thermostat opens in case any air is trapped in the system.

I did left the radiator cap off, the coolant start to fill up and poor out, something normal?

DamianMG wrote: Tue Nov 11, 2025 3:48 pm I did left the radiator cap off, the coolant start to fill up and poor out, something normal?

If that happens, then you put the cap on, let it warm up, then check the level again after it cools down.

On my bike, normally some air bubbles come out soon after start-up. I top it up, put the cap on and let it warm up.