03 WR450 raditor over flow bottle?

I just got an 03 WR450 and it is set up for supermoto. Do I really need to have that radiator bottle thats behind the left number plate. I know its an over flow bottle but why does it have level marks on it, like low and normal. I want to mount my tail light in the place that the bottle is in. I have a 06 YZ250F and it has no bottle. Why the WR's have them and YZ's don't.

I just got an 03 WR450 and it is set up for supermoto. Do I really need to have that radiator bottle thats behind the left number plate. I know its an over flow bottle but why does it have level marks on it, like low and normal. I want to mount my tail light in the place that the bottle is in. I have a 06 YZ250F and it has no bottle. Why the WR's have them and YZ's don't.

YZ's are not designed for grinding it out in 1st gear for long periods of time on some rock and bush infested single track like a WR is. Most guys never go lower than 2nd gear on a YZ. On a sumo you could sit at stop lights for a while, so I would keep it. One thing you could do is swap out to the one made by Motion Pro. It is a smallish (approx 8 oz) bottle that you can mount somewhere up front like in front or behind one of the radiators. There are level marks on the stock bottle to let you know where it should be filled to when cold as you don't want it too full in order to leave room for the fluid from the radiators to expand out to the bottle.

I dont understand why there needs to be fluid in it any way. It dosent do anything. If it fills up, it just spills over on to the ground. And if the level is low, it dosent matter cause thats not what in your radiator. Am I right?

The hose from your radiator to the overflow bottle needs to be full and submerged so coolant and be sucked back into the radiator, just like your car. Coolant expands and contracts with temp

I dont understand why there needs to be fluid in it any way. It dosent do anything. If it fills up, it just spills over on to the ground. And if the level is low, it dosent matter cause thats not what in your radiator. Am I right?

When the coolant gets really hot and expands, the coolant will flow into your bottle INSTEAD of dumping it on the ground. So when the coolant cools, it contracts and then the coolant will flow back from the bottle into your radiator thereby keeping your radiator FULL at all times.

Whatever you do, you gotta stop drinking out of that radiator bottle.:ride:

so its not going to hurt taking the bottle off right, as long as i make sure the radiator is always full, just like i do on my YZ250F. Right?

Leave it on or get the motion pro one suggested. Riding SuMo / street / stoplights will cause you loose coolant without it, resulting in higher temps/ increase endgine wear, higher maintenance costs.

so can someone explain why the YZ dosent have one.

1. different type of riding (30min motos vs 2-3 Hr XC races); At the end of your moto you should go over the whole bike and tighten, replace, replenish etc EVERYTHING so that you're fresh for the next moto. XC riding/racing doesn't have that luxury.

2. For SuMo RACING you'd probably be REQUIRED to have oen so that you're not leaving coolant on the track

3. The YZ was NEVER designed for street use. The WR is street leagl in many places (AUS comes immediately to mind)

You asked for opinions and options. If you don't like them... OK, do whatever you want:ride:

i have a vapor on my 03 and when i sit at stop lights the temp usually rises a good 20 to 35 degrees. sometimes it reaches 200degress. i just installed a fan on my bike so when i sit at lights just flip the switch and a crap load of hot air comes shooting at my right leg. i would keep the bottle if i was you a lot less things to worry about checking and you dont have to worry as bad sitting at lights.

you will boil it over on the first ride . loose coolant it will heat up more and boil out more and loose more coolant and then your engine will seize or your head will warp .

relocate the bottle some were else .

there is coolant in there in case some leaks out then it will fill the rad up automatically , i also don't think it contracts back in the tank properly (would suck air ) if it was empty .

basically they are all like that on everything except for closed cooling systems which are terrible . there is a better reason then the ones i gave you but w.e .

i have a vapor on my 03 and when i sit at stop lights the temp usually rises a good 20 to 35 degrees. sometimes it reaches 200degress. i just installed a fan on my bike so when i sit at lights just flip the switch and a crap load of hot air comes shooting at my right leg. i would keep the bottle if i was you a lot less things to worry about checking and you dont have to worry as bad sitting at lights.

where did you get the fan set up? or did you make one your self?

Coolant expands and contracts with temp

Actually coolant doesn't metal does. As your engine gets hot the metals expand leaving less room for the coolant. The displaced coolant goes into the recovery bottle. Then as the engine cools the coolant is sucked back into the radiator.

i made i my self with a 4in spal fan a bracket i made out of metal. its easy to do. i can tell you how to do if you want

i made i my self with a 4in spal fan a bracket i made out of metal. its easy to do. i can tell you how to do if you want

yes, lets see some pics if you have them, or you can tell me what you did.

Actually coolant doesn't metal does. As your engine gets hot the metals expand leaving less room for the coolant. The displaced coolant goes into the recovery bottle. Then as the engine cools the coolant is sucked back into the radiator.

Actually, the coolant DOES heat up and expand. That's why it boils when it gets to too hot. Granted, the metal ALSO expands, but that's not the reason you have a catch tank. The coolant expands at a MUCH great rate than the metal.

Actually, the coolant DOES heat up and expand. That's why it boils when it gets to too hot. Granted, the metal ALSO expands, but that's not the reason you have a catch tank. The coolant expands at a MUCH great rate than the metal.

When running a vehicle with NO coolant and only water, the water is STILL pushed into the catch tank do to the expanding metals. So a catch tank is STILL required.

Actually coolant doesn't metal does. As your engine gets hot the metals expand leaving less room for the coolant. The displaced coolant goes into the recovery bottle. Then as the engine cools the coolant is sucked back into the radiator.

You are soooo off base, I don't even know where to begin. I'll leave this one alone........:ride:

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