Cooling fans and amp draw on WR450F

[RockyMtnScotsman]

Well, yesterady the fan stopped working. I don't know what part of the relay/temp system failed, but it did. The fan itself is working great, found that out and just hooked it up to a toggle switch for now. Hopefully it is the relay and not the temp. probe that went bad. The relay can be replaced for about $6 but temp probe cannot, its integrated into the wiring harness. The relay just gets unplugged and replaced. I gotta do some testing to figure out which component is bad. Then, depending on what went bad, I may go with a different set up. This thing failed way too soon (third ride) and I didn't beat the hell out of it neither.

so what was the culprit to the failure?

[ur2silly]

I tried replacing the relay but it still didn't work. So I assumed it was the temperature sensor. Disgusted with the whole thing I just pulled the whole fan wiring harness from the bike and rewired it with a toggle switch. It was nice having the auto on/off but still works good with the switch. I think I will just leave it. I would rather ride instaed of messing with wiring.?

[RockyMtnScotsman]

I would rather ride instaed of messing with wiring.

Roger that! ?

Thanks for the update since I'm about to undertake this same mod.

[telejojo]

I put the Spal fan on but had to put it on front of rad. (not enough room on back) with a switch for on and off and works fine.

[MaxPower]

The verdict. Yamaha should have put a fan on these bikes to begin with. :

Im glad your fan works good, You are very innovative to make it work. But I disagree about Yamaha putting a fan on. These bikes are way too heavy to begin with. I cant even lift my bike onto a stand.Adding a fan isnt going to help.They should sell them as a gytr factory option

[Sycamore]

Excellent info thanks for the contribution!!!?

[gjscott]

You can use these cool plastic clips to mount any fan to any radiator:

I've found some:

http://www.summitracing.com/parts/FSS-53014/

[ADVRider808]

I tried replacing the relay but it still didn't work. So I assumed it was the temperature sensor. Disgusted with the whole thing I just pulled the whole fan wiring harness from the bike and rewired it with a toggle switch. It was nice having the auto on/off but still works good with the switch. I think I will just leave it. I would rather ride instaed of messing with wiring.?

Can you comment on the long-term durability of the Spal fan you installed? Also, did you leave it switched or go back to another temp sensor (maybe inline with a coolant hose)?

Lastly, that fan looks to draw about 30W, have you had any issues with the charging system keeping up?

Thanks in advance,

Ken

[DeepPurplishBlue]

Can you comment on the long-term durability of the Spal fan you installed? Also, did you leave it switched or go back to another temp sensor (maybe inline with a coolant hose)?

Lastly, that fan looks to draw about 30W, have you had any issues with the charging system keeping up?

Thanks in advance,

Ken

As the one that originally suggested the SPAL fan in this thread, I can comment on the durability. I use it on a bike in hot humid Asia and run the fan a lot. It gets wet and dirty a lot also and still works fine. This fan has a sealed motor and is designed to work in hostile (wet, dirty, etc) environments. Even for it's size it still moves enough air to keep the bike cool.

I am using a switch on mine, preferring to keep it simple. Also allows me to run the fan when I want to, not when the temp sensor wants to.

The current draw has not been an issue for me, even with slow technical trails. Now if you are stopping the bike a lot in the tricky stuff and restarting it with the button that is going to catch up with you eventually but that would happen anyway even without the fan.

[Sknight]

I got the same Spal fan on mine and power draw has been no issue, in fact I've let it run for several minutes with the engine off and it's not made a dent.

[ADVRider808]

DPB,

Thanks for the update. I just need to make sure it will fit with the Acerbis tank (3.1gal) I have available to put on the bike. I had planned to add a voltage meter to monitor the charging system, but that may not be necessary. I also plan to use one of the new Lithium batteries, the A123 variety, that has a bit more juice than the stock lead acid unit.

Ken

[ur2silly]

I have not had any issues with the fan drawing too much current. There have been several times where I turned it on and ran it for at least an hour while riding with no problems at all. I never did go back to the temperature sensor/relay to control it. The switch still works fine for me and like I said before I would much rather ride than mess with wiring. ?

The fan's durability has been great. It has been covered in mud, sand and all sorts of general grime. I just spray off the fan when I do the bike with a hose and have never had to worry it. Water does not affect it at all.

All in all I would recommend this fan as it does it's job very well.

[GlennR]

I'm thinking about ordering a fan. My "new to me" o8' overheated on an extrenely slow rocky hilclimb. I probably won't ride that slowly often, but if I do in the summer time I'll be in trouble without a fan. Seems the price is up to $55 on ebay now, darn-it!

[Mtn-Track]

I have a 2008 WR450F and was about to ghost-ride it off a cliff due to overheating issues. Engine Ice helped, but not nearly enough for high altitude, warm days, and lots of slow technical riding.

I bought two of the SPAL 4" Paddle Blade PUSH 12V fans from E-bay. It turns out the 4 mounting holes on the fans span the support rods on the front of the radiators nicely. I used 4 Adel clamps on each fan to attach them to the supports with machine screws and lock-nuts (Adel clamps are the little metal cable clamps with the rubber inserts you can get at Ace Hardware). This put the fans right in the center of the radiators, in the front, and keep the engine and radiator heat from cooking the fans. I also have the Clark tank where there isn't enough room to put a fan between the tank and radiators anyway. I cut the factory rock deflectors around the fans using a Dremel and used clear silicon to secure the loose deflector fins to the fan housings. I power the fans with a waterproof on-on switch and a 25amp AC-to-DC module from Radio Shack (total $7.00). Both fans together pull slightly less amps then the headlight. I have the switch on the handlebar next to my left thumb so I can switch back/forth between the headlight and the fans (when needed). This kept the system simple and I have yet to even come close to overheating!

If you do lots of riding at night, I've found the cooler night temps keep me from having to use the fans very much. If I do need to cool it off, I just stop for a few minutes and run the fans while on high idle and then I'm off again. Obviously you can get more creative if you have a different stator and/or a full DC power system (and ride on the street at night) but I already spent enough on other parts and didn't feel like dumping any more into it. I think I ended up with about $75 in the whole set-up.

On a different note, I don't run the fans at the same time we're blazing down a trail and someone in front of me is kicking up rocks and dirt. Don't need to for cooling. However, when they are not running they have protected my radiator as well as the facotry deflectors do and still don't show any damage after a year.

Edited March 26, 2012 by Mtn-Track

[GlennR]

I was looking at my 08' today and wondering if the pull fans would fit behind the radiators. I didn't think they would. The OP said they fit on his, but something must be shaped dfferent on the year he has.

I'm going to just start with one fan and see if it cools enough.

[Mtn-Track]

The Spal 4" fans will not fit behind the radiators with a Clark 3.6 gal tank installed. If you managed to wedge them between the two then you would have the fans rubbing against the tank and no airflow. With the stock tank they might fit down in the corners of the radiators, but they probably won't last as long being trapped between the radiator heat, engine heat, and exhaust heat.

If I rememeber correctly, the two fans together pull about 4.4 amps and the headlight pulls about 5 amps.

I wanted to get the amp draw close on fan start-up so I didn't keep surging the rectifier everytime I switched between them.

.

Edited April 2, 2012 by Mtn-Track

[n16ht5]

Im glad your fan works good, You are very innovative to make it work. But I disagree about Yamaha putting a fan on. These bikes are way too heavy to begin with. I cant even lift my bike onto a stand.Adding a fan isnt going to help.They should sell them as a gytr factory option

my wr is about the lightest bike I have had aside from my honda 90s. what are you talking about?

thanks for the pics, I might try this mod soon

Edited March 27, 2012 by n16ht5

[heller44]

Mtn-Track, fairly sure which ones you have from the pics, but it might have been better to get push fans and mount them on the front like you have done with pull fans in reverse. Those spal fans have a cfm difference running the wrong way of almost 20cfm.

for anyone else going this route I thought I'd just add this bit.

[Mtn-Track]

Mtn-Track, fairly sure which ones you have from the pics, but it might have been better to get push fans and mount them on the front like you have done with pull fans in reverse. Those spal fans have a cfm difference running the wrong way of almost 20cfm.

for anyone else going this route I thought I'd just add this bit.

HUH?

The fans I have are PUSH fans, mounted on the front of the radiators....

The motors on the 4" Spal fan units are the same. The fan blade units on push and pull fans are the same. The blades on the fans are symetrical. As such, the motors and fan blades don't care which way they are spinning, they run the same RPM and move the same amount of air. That being said, the "push" fan needs to draft air around the housing and motor, thus they have a lower CFM than the "pull" fan that drafts in 'clean', unobstructed air.... normally. You put a pull fan behind a radiator and you have now eliminated the 'clean' air source for the fan and the CFM drops off dramatically. Then add the high-temp air that the fan is drawing (less dense) and the fan CFM drops off even more. Take a push fan and install it in front of the radiators and the CFM into the fan remains the same, plus your drafting ambient-temp air. As a result, the fan in front of the radiator will end up moving more air into the radiator and the fan will also not be drawing high-temp air past the motor = more efficient motor with longer life.

http://www.spalusa.com/pdf/30103009_SPEC.PDF#view=FitH

Just my 2 pennies worth...

Edited April 4, 2012 by Mtn-Track

[GlennR]

Since the Spal fans are $55 now I might just get a used fan from another bike off ebay for $10 or so. The computer fans aren't waterproof and I figure most used motorcycle fans probably are only "lightly used" since bikes don't usually get the high milage like cars do.