Missing coolant from overflow bottle

So I checked the coolant overflow bottle today and to my suprise there was no coolant on it, it's been a while since I checked it (yeah I know I should check such things more often   ). I also checked the rad and that was pretty much filled to the top and there was no oil residue in either the rad or the bottle which I took of and cleaned out, there did however seem to be some dirt in the bottom of the bottle and I can't see a coolant leak but it is possible.
  Does anyone have any ideas on what may have caused this to happen, I have dropped my bike quite a few times in the dirt, would that cause it to leak out the overflow? What about high speed runs, could they also cause the coolant to boil over?

Thanks to anyone that can help.

Our bikes have an overtemp light on the instrument cluster. If the light doesn't come on then your bike isn't over heating.
I would check the engine oil, make sure there are no signs of water contamination. excessively white exhaust smoke would also be a bad sign.

I would fill it up, leave the black guard off so you can monitor the coolant level and drive it around town. Make sure the level goes up when hot and drops back down when cool.

When was the last time you saw coolant in the reservoir?
Just how long has it been?
Doesn't the bike have a handy slit in the front of that plastic panel to give it a peep?

Actually, I believe there are a lot of bikes running around with empty coolant reservoirs because no coolant was added to them when the bikes were assembled and pre-delivery serviced at the Yamaha dealer.
Thank God the engine comes with engine oil already in it, huh?

Dumping the bike on it's side and/or upside down can eventually drain the reservoir because the reservoir, itself, has a drain hose that simply points down at the ground.

You should keep some coolant in the reservoir because, otherwise, your cooling system will tend to suck air when the coolant cools down and contracts.

If it were my bike, if I hadn't done it in the past 2 years, I'd change the coolant.
It's easy.

They actually do come without oil. The dealer has to add oil and battery. Like a lawn mower. Lol

Not at the Yamaha motorcycle dealers I've been with since 1987.
They are instructed to check it, but not having to fill it.

Where are you from?

Just quoting what they told me when they prepped my bike at martinsburg motorsports.   

Yeah I changed the coolant within the last two years just cant remember when hahaha. The bike has been down a few times as well in the trails, I also noticed when I refilled the reservoir that the rubber cap can be difficult to seat properly and may not have been on right since I changed the coolant so that may explain it as well.

bracky72 wrote:

Just quoting what they told me when they prepped my bike at martinsburg motorsports.   

They're full of excrement.

yeah, they are shipped with oil and all required fluids....it's the dealer's resposibility to assemble and check the unit over...now, if the dealer sucks, well.......

sorry, they don't come with gas..