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on the ktm fan kit does anyone know what the circular airflow per minute (cfm) rating is for the fan because i found 120mm waterproof fans on mouser electronics for $20 a peice and was gonna rig up my own fan kit

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I think it is close to 200 CFM's.

120 CFM should be enough as long as you don't have a real bad over heating problems. You can also get a thermal switch from NAPA that fits an older model 318i. Its 18mm.

Can you post a link to the fan you are talking about?

I have been running the Sidewinder fan on my for for a couple years with no problems.

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120mm computer fans don't put out anywhere near the CFM (cubic feet per minute) of the KTM fan and they're not waterproof (though they may last for a while). Better to just buy the KTM fan kit that comes with a nice bracket and thermostatic switch, and plugs into your factory harness.

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on the ktm fan kit does anyone know what the circular airflow per minute (cfm) rating is for the fan because i found 120mm waterproof fans on mouser electronics for $20 a peice and was gonna rig up my own fan kit
120mm computer fans don't put out anywhere near the CFM (cubic feet per minute) of the KTM fan and they're not waterproof (though they may last for a while). Better to just buy the KTM fan kit that comes with a nice bracket and thermostatic switch, and plugs into your factory harness.

well you caught me on the cfm :lol: but the ones that i did find were not computer fans they were heavy duty 2 Amp powersupply fans that put out around 80 CFM

http://www.mouser.com/Search/ProductDetail.aspx?qs=sGAEpiMZZMvuXzJ9NcThauZgWwIac4iLLNNXfZVgSbA%3d

but since you said that they arent water proof ill just use one of these

http://www.mouser.com/Search/ProductDetail.aspx?qs=RnLyf%252bIy6kGj8%2f3vF4KK6g%3d%3d

or if i wanted to go over board ill use one of these

http://www.mouser.com/Search/ProductDetail.aspx?qs=sGAEpiMZZMvuXzJ9NcThanDqKRDxPVQdpreiSMdFtn0%3d

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The OEM fan is 124 cfm at 1.9 amps at 0 static pressure. It does move a shirt load of air and really works good. Don't discount the shrouding it contains as it increases the flow.

This is the FAN that the OEM uses, minus the shroud.

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eagle eyes... what bike are you trying to fit a fan on?

the KTM hard parts fan that also comes with all the necessary installation parts isn't much more ($101) than fan in your second link($75), and much less than the fan in your third link($200). why wouldn't you just use one from KTM?

the $101 was for an RFS exc model at ktm-parts.com... the fans for the XC4 motors were a little more expensive at $127

https://www.ktm-parts.com/mm5/merchant.mvc?Screen=PROD&Store_Code=K&Product_Code=78035041044&Category_Code=KTMHEEA

https://www.ktm-parts.com/mm5/merchant.mvc?Screen=PROD&Store_Code=K&Product_Code=59035041044&Category_Code=KTMHEEA

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There is very limited room to mount a fan.

Anything over 120mm will be a challenge.

The KTM fan is a good deal and is the way to go if you have cronic over heating problems that you can not correct with jetting. There is also down sides to the KTM fan also. They draw a lot of power. IMO, you need to upgrade the stator when you do the KTM fan. They block a lot of air when they are not running. Which makes them run more. They are noisy.

The computer fan is a good match for a bike that may over heat only in the slowest, tightest riding. It is just a little extra insurance. They don't block much air when they are off. They draw very little power. They are quiet. They are cheap if they break. I have dropped a computer fan into a bucket of water and it keep on running. I was surprised.

First step is jetting. Then decide how much cooling you need. Some people just don't need the KTM fan and it creates other problems. For some people, the KTM fan is the only fix.

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Hey there, new KTM owner, reading up alot about the cooling fan that many are running and I have a question: I have already installed a computer case fan of my own, tied it to the headlight so that its not directly draining the battery. However, the fan came with 3 wires leading from the fan, a red, a black and a yellow??? I connected the red to the red on the headlight and the black to the black and it runs fine, just very slow and I'm guessing its not moving much air, if any at all. My question is, how have all of you all installed your comp fans? Will that 3rd wire affect how fast the fans turns? any help you guys could give me would be great. Thanks.

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Hey there, new KTM owner, reading up alot about the cooling fan that many are running and I have a question: I have already installed a computer case fan of my own, tied it to the headlight so that its not directly draining the battery. However, the fan came with 3 wires leading from the fan, a red, a black and a yellow??? I connected the red to the red on the headlight and the black to the black and it runs fine, just very slow and I'm guessing its not moving much air, if any at all. My question is, how have all of you all installed your comp fans? Will that 3rd wire affect how fast the fans turns? any help you guys could give me would be great. Thanks.

Using a 12v battery, try connecting the black to the neg, then first touch the red to Pos, lift it off, then the yellow to Pos, see which one runs faster..

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The third wire (yellow) is for speed monitor for a computer motherboard. Do not connect it to anything.

Unless you have done the DC conversion, the head light is AC.

There should be a connector under the gas tank for the OEM fan to connect to. Tap into this connector for your fan. It is a fused link to the battery.

Some people have installed a rectifier to the head light AC to convert it to DC for the fan. The computer fan draws such a small amount of power that it should be fine connected to the battery.

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The third wire (yellow) is for speed monitor for a computer motherboard. Do not connect it to anything.

Unless you have done the DC conversion, the head light is AC.

There should be a connector under the gas tank for the OEM fan to connect to. Tap into this connector for your fan. It is a fused link to the battery.

Some people have installed a rectifier to the head light AC to convert it to DC for the fan. The computer fan draws such a small amount of power that it should be fine connected to the battery.

I have done this rectifier mod and it works great. Check the sticky for the how-to complete with pictures.

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Im going to attempt the comp. fan mod too. Some people told me to use a 3-way switch. One for on, one for theromstat w/fan on, and off.

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personally i dont think that a regular computer fan will move that much air. do you have a link to what fan it is??

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Hey there, new KTM owner, reading up alot about the cooling fan that many are running and I have a question: I have already installed a computer case fan of my own, tied it to the headlight so that its not directly draining the battery. However, the fan came with 3 wires leading from the fan, a red, a black and a yellow??? I connected the red to the red on the headlight and the black to the black and it runs fine, just very slow and I'm guessing its not moving much air, if any at all. My question is, how have all of you all installed your comp fans? Will that 3rd wire affect how fast the fans turns? any help you guys could give me would be great. Thanks.

I think the headlight runs on A/C and you've probably connected a D/C fan. Replace with at 12V A/C fan and that might work better.

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Extending the computer fan idea a little bit, one might try using a couple on the left radiator in addition to the right side. Even though they move less air, a few fans pulling less are, but doing so over both radiators should help.

I did this on my old KLX250S after I installed a larger gas tank, the stock fan would not fit. So I used some weather proof comair rotron fans, I think they were 60 mm, but I used two on each side for 4 fans total. They worked very well and never had any problems, I even sprayed them directly with the hose when cleaning the bike and they always worked fine. They went with the bike when I sold it, I don't know if they are still going or not.

Left side:

100510211_qDGww-L.jpg

Right side:

100510308_tKgCP-L.jpg

100510427_5HZaN-S.jpg

They don't push a huge amount of air, but put 4 of them together and they are adequate for most purposes, and are light and don't draw a whole lot of current so they won't drain your battery under normal use. But they are not going to keep you form boiling over if you are stuck in a mud bog and gunning it for 30 minutes, though.

As L-Vie says, they will definitely take the edge off if you have occasional overheating problems and I think that's probably the case for most folks where the stock fan is a bit overkill. I have a stock fan and had it installed but I ended up removing it. I may put it back on for summer. I took it off because a few months after I installed it, my battery went kaput. Might be coincidence because I was pretty hard on it with the e-start for a few rides, and then a connector came loose on one ride and it was not charging at all and ran completely down - very deep discharge. So I'm sure that wasn't good for it. But it would never hold a charge after that. I replaced it with a new one, but I have not put the fan back on. I've done the DC stator mod, but not sure if I should put the fan back on without upgrading the stator or getting it rewound to put out more juice. But my bike does not have a chronic overheating problem, so I think I'll just leave it off and see how it goes, I can always put the fan back on if it starts acting up.

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thanx for the idea nobrakes maybe ill try what you did first before i go out and buy the fan kit. i also like what you did with the white out

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"I think the headlight runs on A/C and you've probably connected a D/C fan. Replace with at 12V A/C fan and that might work better."

Great idea, I will try that tomorrow, strange though that the fan is running off the AC current even though it is a DC fan???

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One question, hopefully someone knows, what voltage is the AC current going to the headlight??? So, that I get the right voltage fan. Thanks in advance.

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I believe the ac to be 12-14 volts. the system has a rectifier for dc but no additional voltage regulator

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