Boysen water pump VS fan

I'm putting a Revloc on my '09 WR450...I know this will make it run a little hotter on tight trails. To offset this, I'm deciding between putting a fan on the right rad, or putting in a Boysen water pump.

Have any of you tried either, and what were the results? Right now I'm leaning towards the Boysen...any feedback would be appreciated.:thumbsup:

Do the fan. No comparison in performance. The only down side is remembering to turn it on/off and the extra weight.

With a pump,no matter what it doesm, you still have to shed the heat. Just because the coolant moves better means little when the heat is retained. To shed heat at slow speeds you need a larger radiator or a fan (or a real strong wind to ride into).

If you can run a fan, do it. For the others that can't use EVANS COOLANT & the Boyesen Super Cooler. I have the Boyesen & the impeller is larger & the Water Pump Cavity is Larger & Smoother. Does it help to cool the bike? I hope so.......

The primary benefit of the Boyesen water pump cover and impeller is reduced parasitic drag on the engine, not increased cooling. It does increase the flow volume somewhat, but that won't necessarily increase cooling. If the increased velocity means the water flows through the engine too fast to pick up enough heat, or flows through the radiators to fast for enough heat to be shed, you may actually have reduced cooling.

I would go with the fan if you find that you need additional cooling.

If you guys think a fan is the way to go, then a fan it is. Thanks guys:worthy: Now, I need to find a place to get a fan...

Rather than worrying when to turn it on or off I would install some type of thermo sensor to turn it on and off for you as needed.

Most that want to install a fan, simply get a computer fan. They are cheap, 12volt. Do a search on 'Computer Fan' and you may get some good results.

Since I haven't removed the AIS, it doesn't look like I'll have room for anything but a small computer fan, which I'll try.

I'm wondering if part of the heating problem is the proximity of the header to the right rad...it clears the rad by @ 1 inch. Has anyone ever tried to wrap the header as it goes under the rad, or fab up a small heat shield to protect the rad?

I woudn't do anything. The 450 gets hot and sends some coolant into the puke tank. When it cools off it pulls it back. It never seems to hurt the 450's, they run forever.

Try EVANS WATERLESS COOLANT. It's about $40 a gallon, but works GREAT!! If your bike pukes with Evans than do what you have too.

try the chinese radiators on ebay. 30% more capacity. my 450 with rekluse has never overheated since installing them. we ride all single track here.

Most that want to install a fan, simply get a computer fan. They are cheap, 12volt. Do a search on 'Computer Fan' and you may get some good results.

I wouldn't use a computer fan, as they are not waterproof

I wouldn't use a computer fan, as they are not waterproof

True, but they are 'dirt cheap' and can be considered like goggle tear offs.

Since I haven't removed the AIS, it doesn't look like I'll have room for anything but a small computer fan, which I'll try.

I'm wondering if part of the heating problem is the proximity of the header to the right rad...it clears the rad by @ 1 inch. Has anyone ever tried to wrap the header as it goes under the rad, or fab up a small heat shield to protect the rad?

Header makes little difference. It is all about airflow through the radiators. If the speed is consistantly less than 10 mph, you will have problems.

Header makes little difference. It is all about airflow through the radiators. If the speed is consistantly less than 10 mph, you will have problems.

True enough William1...I think the best way to keep 'er cool will be to ride a little faster! :thumbsup:

I've been having some overheating issues on my 2t yz250. It's bored to 285 AND I'm running a rekluse but I think I've traced the problem back to jetting. I did the Shane watts dirt wise hardcore class a couple weeks ago and it was running so lean and so hot it started to idle really really high. It got to the point that the kill switch wouldn't kill it so I pulled the spark plug wire...after shocking the shit out of myself I found my bike just sat there high idling away...it was so hot the spark plug was no longer relevant! Time to spend some time with jets needles and clips! If only I were smarter...

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