XR650R Dualsporter: Fluidyne rads + fan

First time poster. OK, I'm slow and old but I catch on after a while...:ride:

Put on a pair of Fluidynes, as my stock left was sprung from a lowside four years ago and started leaking this year. Man, these things are stout. I suppose no one needs to run Devol guards with them? Or do ya?

The other issue, I have a KTM fan I intended to install, but the rads are pretty thick and there is precious little room to slip it between the right rad and the Clarke tank. Also, the handy tabs from the stocker are not on the Fluidyne. I suppose I could epoxy on some aluminum tabs. In the 4x4 world, guys just run threaded rod through the radiator but geez I don't wanna do that to these beauties. :ride:

Anyone run a fan with these? I also have a sealed, wet environment high temp muffin fan that would fit but it won't move much air in comparison to the KTM fan.

Hey,I don't have a answer,

But , Welcome to Thumpertalk..:ride:

:ride: :ride:

Hi RC,

Yellow Pig from ADV. I see you are scowering the net for this info.

I just swapped back to my Clarke 4.7 tank. The Acerbis 6gal is just too big most of the time and realy cuts down on the BRPs wheelie power here at altitude. I found that I had to remove the fan too to get this tank on. While the acerbis has a nice wide fit w/ the sides of the tank acting as air scoops (so you can fit the fan) the Clarke contours tightly around then rads making it impossible to mount. I would think a cheaper fan that doen't move enough air would not be worth the pain to install.

Later Dan

Hey Dan, yep- don't mean to flood, but it seemed like it was one of those questions for a real unusual configuration. Interesting response on ADVrider.

I suppose before I go welding on these new beauties, I need to establish that anyone has found a fan NECESSARY when dualsporting (and commuting) with Fluidynes. I'd rather not find out in July... :ride:

I did employ the heat gun to reshape part of the Clarke tank to go around the little rad-to-rad tube on the right rad... Could use it to make a bit of room for a fan too. Don't wanna get too happy with the heat gun though, or I will end up seeing how an IMS tank compares with the clark... :ride: :ride:

They make plastic zip ties for mounting fans/oil coolers to radiators, that would be much better than threaded rod.

:ride: Picked some up yesterday - simple solution! Thanks for the idea.

Try a 1.6 or 1.9 radiator cap? That can help the boil over from happening. Also, if you leave your bike in a warm place that won't freeze, you can use water plus wetting agent instead of antifreeze coolant for about 20% gain in cooling capacity. Its more efficient than antifreeze. With the higher pressure cap and water/water wetter on stock radiators, you can get more cooling and less boil-over than fluidyne radiators with antifreeze.

I'm guessing that you are using a fan because you are stopping with your bike idling, hill climbing, or slow trail riding and getting boiling over. In these cases, the fan is probably best since you don't have much air moving through the radiators.

No fan yet. NIB KTM fan looking for a place on the right rad! It's tight with the Clarke 4.? tank. Been running a high pressure cap and hi temp thermostat with Honda coolant and water wetter since 2001-2002 or so. They do make a difference. Also made sure the needle was set fatter, as well as the pilot. These too made a big difference.

Only boiled a few times, for instance, struggling up Blanca Peak (boulders anyone?) in first. Since I am now dualsporting it in earnest, I want to have extra insurance should I get caught in a traffic jam. That, and I'm 6 years older and slower...

I'd like to thermostatically control the fan rather than manually, too, as a way of letting me know things are hot. Any thermoswitch ideas? The KTM thermoswitch is a bit big for the thermostat housing if looks can be believed.

Not thermoswitch related, but turbo miatas can be really tough to keep cool because the intercooler blocks flow to the rad. One of the most common remedies is to go down to ~30% coolant/70% water. You give up some anti-freeze capability (as in, keeping the coolant from freezing) but get significantly increased thermal transfer since water does a better job at that than glycol does. Might be worth thinking about, especially if you're in an area that doesn't go to -34F...

I ride mine on the street in the AZ summer. I've got stock rads and never had an issue. I'd think that the Fluidynes by themselves would be adequate. :ride: Where you having overheating problems before?

In my experience, a little bit richer than ideal pilot circuit (which is probably imperceptable to most of us--espeically in a commuting scenario) is sufficient boilover protection unless your rockcrawling or want protection you'll probably never need.

I just sat from a cold start slowing reving my bike the other night for about 5-8 minutes and it boiled over? Is this normal? Stock rads, but uncorked?

Was it a hot day when you were idling for 5-8 minutes? If you are riding and sit and idle for 5-8 minutes, it will boil over. If you just started it, then it takes time to warm up and will be ok for 5 minutes....but 8 minutes might be pushing it.

I think you might be running lean. Running lean causes your bike to run hot. You can verify by checking your spark plug. Does your sparkplug have white, grey, or brown residue on the electrode? White is lean, dark brown/wet is rich. You want light brown.

Did you put in the 68s pilot jet? What is your airscrew at on the right side of your carb? It should be 1.5-2 turns out from bottomed.

Hope you can figure it out.

Was it a hot day when you were idling for 5-8 minutes? If you are riding and sit and idle for 5-8 minutes, it will boil over. If you just started it, then it takes time to warm up and will be ok for 5 minutes....but 8 minutes might be pushing it.

I think you might be running lean. Running lean causes your bike to run hot. You can verify by checking your spark plug. Does your sparkplug have white, grey, or brown residue on the electrode? White is lean, dark brown/wet is rich. You want light brown.

Did you put in the 68s pilot jet? What is your airscrew at on the right side of your carb? It should be 1.5-2 turns out from bottomed.

Hope you can figure it out.

yes, 68S, 175 main, comp needle third seat, but I have never checked the airscrew- do you run the bike while adjusting the air screw or?

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