Second fan on 5th gen

Here's a modification I'm thinking of doing in conjunction with the VTR fan blade (the new blade is on order: the slow traffic and hot weather in Melbourne have been frying my nuts lately).

To minimise any negative effect of using the VTR fan blade while stationary, I'm thinking of adding a second fan to purge the area around the front headers, and bring in more cool air. I have an old fan from a ZZR250, and it fits in the general area.

What are people's thoughts on the idea?

 

Worth a shot. I wonder how long it will last with dirt and water hitting it.

 

It lasted about 40,000km in the ZZR before it failed. It probably won't last as long this time because it's already old and tired (although it's now clean again inside, thanks to a little "elbow grease" last night). It should be ok as a proof/disproof of concept. Ideally I'd like a fan that's slim enough to put directly in front of the oil cooler, but this one's too thick (will foul on brake cables when the front compresses during hard braking, if I put it between the oil cooler and the fork).

Has anyone else tried a purge fan with a VTR fan?

 

That is NOT a good place to fit it. The curved cutout in the front cylinder head cover is so the front wheel does not hit during heavy braking ! It will hit that fan. Put a FAN on the right rad, to boost cooling capacity & use a lower temp fan switch & hey presto, it never gets hotter than 95c. Do a search, I've posted threads on this.

 

Thanks for the advice, Mohawk. You have a very good point there. I kinda forgot that the tyre moves backward under compression (not only upward)... Oops! Good thing I thought I'd check here first, instead of finding out the hard way! Thanks again Mohawk!

 

Here's the link to Mohawk's modification, if anyone's interested:

http://vfrworld.com/forums/5th-generation-1998-2001/39048-extra-cooling-right-side-radiator.html

 

Alrighty... Here's another brain fart... I mean brain wave I just had. Same fan. Reverse the blade, and wire it in backward, then jam it in between the sump and the header. The idea is to blow the hot air down and out the bottom of the fairing. Of course, some minor hose re-routing/protection would be required, and the fan housing would have to be cut down to size...



Also, I've installed the VTR1000 fan blade, and it works so far. However, at 21'C ambient, it took a while to get the fan to turn on...

 

Something to possibly consider would be installing a single pole double throw switch to the stock fan. After installing this, I can now select the fan to operate automatically from the thermo switch , or I can force the fan off, or force it on - no matter the engine temp. The switch has 3 terminals. The wire that presently goes to the thermo switch (which is hot) is re-routed the swtich's center terminal. One of the switch outer terminals goes to a ground, the other outer terminal to the thermo switch. I bought a few blade connectors at a parts store and made a couple of jumper wires that I just plugged in so I did not have to cut any stock wiring. I switch the fan on when slowing in traffic at around 190 degrees before a lot of heat can build up, and then once I get rolling I can switch it off once I exceed about 25 or so mph which eliminates the "fan fighting the airflow" issue. This has reduced my cooling system issues significantly. I've run this for about 2 years and it works great. Cherry Electric makes some nice waterproof mini-rocker switches that are inexpensive.

CHERRY Waterproof Rocker Switches and Push-Button Switches

I did slip up a couple of times where my temp was really climbing and I was thinking "WTF?*?*?" until I realized I had left the switch in the off position. That was like locking the keys in the car - you'll only do it once. Now I control the fan without even much thinking about it.

 

I think I would be more concerned about taxing your electrical system. What kind of amp pull is that fan going to draw?
You wouldn't think it would be a whole lot, but stock fans are terribly ineffecient when it comes to that kind of stuff.

From everything I've researched, the stock VFR fan has a constant 9 amp draw, which means it probably pulls more in the area of 27 amps when it kicks on.

Yes, things like this keep me awake at night. LOL

 

The ZZR fan should pull about 7.2 A once it's running (13.6 V, 1.9 ohm). I'm sure my MosFET RR is up to the task, so it's just a matter of adding a new circuit to the battery, and adding a relay to turn the power off with the key. I'll even wire the heated grips into it so I can't give myself another flat battery...