Aftermarket cooling fans?

[CorriganJ]

Hi all. Looking to install a second fan on my 1991 Africa Twin. It only has a fan on one radiator, I've seen people install a second with a manual override switch.

Was just looking around, and I can find a second hand fan for £40 including shipping, but I'm wondering if a modern fan would be "better"? Better in this context would probably mean more efficient so it drains the battery less, and good cooling flow, although I assume they are all much the same when it comes to that?

So yeah, pay £40 for a 30 year old fan, or get a new one? Thanks.
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1991 RD04

[stinkwheel]

Why. Is it overheating?
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[xX-Alex-Xx]

Other option is to fit a manual switch in parallel with the temp sender on the radiator to give you manual control over the fan, but keep the automatic function going should you forget... Considered doing this to my 929 for if/when I was stuck in traffic but never got around to it.
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DILLIGAF

[CorriganJ]

[ThunderGuts]

Yes, wattage is power and calculated by multiplying the current in amps by the voltage. So you're right, a higher wattage unit will drain more power from the electric system/battery. Barring relatively small differences in motor efficiencies and fan blade design, wattage is however going to be directly proportional to cooling capability, so if you're wanting to increase cooling you're going to increase power drain. If the issue was on the move, you could theoretically improve things with a second radiator (which wouldn't affect your power drain) but if your issue is with very slow riding and therefore not much air movement, you'll probably need a fan on it to move the air, so you're back to square one.

I would look closely at the state of the radiator you've got. If there are a load of bent fins from stone impacts over the years, or it's full or crud, or both, then it won't be as efficient as it could be. If it is in a bad state, I'd start with getting a new radiator which will be a lot less faffy than trying to install secondary cooling fans (which again won't reach their potential if the radiator is in a bad way).
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TG.

[jaffa90]

A fast tick over / idle speed with a very weak mixture could cause more heat.

[stinkwheel]

In fairness, people ride the length of Africa on them totally standard so you have to wonder if there's another factor at play. In addition to the above, worth checking the thermostatic valve is fully opening too.

What about fitting a higher spec oil cooler? No power draw there.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Easy-X]

There anything on the clocks/dash that can tell you the current coolant temperature? How hot is it getting?
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Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[CorriganJ]

[tatters]

My 1992 BMW R100GSPD would chuck along fine moving in Morocco/Sahara in heat in the mid 40,s but sitting in traffic in London the bike would start to overheat (oil temperature to the point the oil would start breaking down). Air movement makes a big difference on both air cooled and water cooled engines.

I have never had to fit a second fan before but have found that a manual override switch wired in parallel works very well to put the fan on long before the bike thermostat does. Both my ZZR600s had this for riding in heavy traffic.

I have also changed out the thermostat switch on a KLR650 to a lower range so the fan would kick on sooner at a lower temperature this worked quite well as a automatic solution without the need for a manual switch.

One interesting caveat with a manual fan switch is to make sure it is off when taking a dual-sport/dirt bike though deep water as the cooling fan will break if it water hits the blades while running. Not that many riders will face this but l have seen it happen on one bike.
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Past:NRG50,AF1125(x2),NSR125RR,ZZR250,CX500,VFR400,KR1S,ZZR600(x2),CB400N,YZF1000(x2),KH125,Z200,FX400R,CBR954RR(x2)GPZ500S,GT550,VFR750F(x2),RD350N,XR650R,CBR600F,CB250,KDX250,YZF750R,CRM250,400EXC,KLR650,TTR600RE,DR350S,R100GSPD,RGV250,VMAX1200,DL650 Present:G650XC,C12,KZ750,1190ADV

[WD Forte]

This guys done it,( link below) looks easy enough.
Going by his negligible voltage drop and the physical size of the fans
they don't draw much power.
It looks like he knocked up some brackets and fitted a
stock (SH?) one on the left rad.
Personally I'd go new as many bike fans don't lend themselves to
easy fitment of new brushes and you don't know what sort of life will be left in a SH one.

This 7" push/pull type on Ebay is just £17.50
https://www.ebay.co.uk/itm/284657635386?

It says it's 80W but I suspect that's Chinese watts, the
10" one on my old CX was more like 50W and didn't half shift some air

https://www.youtube.com/watch?v=7-w0xe2gYFs
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bikers smell of wee

[CorriganJ]