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Manufactured heat exchanger kit (Full radiator delete) for sale

I dont keep the bike at home, but I can do that next time I am near it. I am just running the timbersled scratchers for Aro and Riot kits.

Oh, I gotcha. So scratchers hanging off the rails. Rails scratchers are a bit more complex with the narrow rails of my Yeti, but I think there are solutions that could be made to work. Same with getting the duraflex ski scratcher, I bought, to work with the upturned CMX ski; there are ways, but not straight forward. If I can get scratchers to give me enough trail tunnel cooling, then I won't have to rework my radiator delete and re-install one radiator. I'd rather spend my time solving for scratchers than re-installing a radiator. Time to get out in the shop to stare and think.
 
ARO scratchers fit well on my narrow rail timbersled. I run the XRT cooler with no radiators. I've even got it placed way up in the tunnel and it cools fine. I never got below 160F diving into waist deep powder on a -10F degree day. The scratchers kept it at 175 to 180 on hard snow trail.
 
Oh, I gotcha. So scratchers hanging off the rails. Rails scratchers are a bit more complex with the narrow rails of my Yeti, but I think there are solutions that could be made to work. Same with getting the duraflex ski scratcher, I bought, to work with the upturned CMX ski; there are ways, but not straight forward. If I can get scratchers to give me enough trail tunnel cooling, then I won't have to rework my radiator delete and re-install one radiator. I'd rather spend my time solving for scratchers than re-installing a radiator. Time to get out in the shop to stare and think.
Yeah, same as Dr. Z I have the narrow rail Aro3 and they work well. At least on a hard packed trail. I haven't been on a true ice trail yet.
 
I am running just regular Prestone coolant. I have found it to be more readily available so I run that on my snowbike in case I ever need to "top it up".

I figured out that my thermobob thermostat was old and it wasnt opening and closing correctly. I replaced it with a new internal thermostat and this is my experience now:

- Riding in any powder the bike is near perfect temps all the time. It will sit between 160f and 180f all day without issue.
- On the trail, without scratchers I will overheat pretty quick. I have two ice scratchers now and it keeps the temp gauge right at 180 all the way down the trail
- However, even though the gauge reads 180, the clutch will lose pressure and I get excessive freeplay if I am on the trail for a while. If I stop and open up the engine blanket and throw some snow onto the clutch cover it goes away. I am not sure what is going on there. I have purchased a new clutch and will see if that solves the problem.

Other than the wierd clutch issue I have no complaints. It seems to be working fantastic.

Stay away from evans coolant. The regular stuff works best.

Clutch issue- check your clutch fluid first, I have had that happen. Old fluid looked gray and like it had water in it.

Good to hear your setup is working much better! If you ever decide to- I can set you up with a bigger heat exchanger.
 
Stay away from evans coolant. The regular stuff works best.


Dave, why stay away from Evans waterless coolant? I switched to it last year and it performed great. If one ever accidentally got a little hot, no boil over so no fluid loss because there is no vapor pressure/expansion since Evans doesn't boil until 375 F. I'm not aware of any cons except that it's proprietary and you can't top off with any other coolants or water. Well, you can just to get home if absolutely necessary, but it means draining, flushing/prepping, and redoing with Evans again. I haven't added a drop all last year where, with "regular" coolant, it seems I'd boil some out fairly often; one time I boiled out enough that my coolant-heated bars didn't work on the ride out so that was a miserable -10F, 15 mile ride out. Ha.
Evans is a bit thicker than water, but seems to flow just fine in powersports applications. Works great so far this year after my radiator delete/tunnel cooler install and it's even saved me a lot of grief/boil overs as I figure out my trail/scratcher setup as I've not boiled any Evan out where other vapor pressure coolants would have.

So curious to hear some of the reasons you recommend staying away from it? I'm open to more data and always willing to re-weigh the pros and cons as new info is presented. I guess as part of that, when you say "the regular stuff works best", I'll ask you to define "works best" since you may weight some aspects higher/different depending on your use case. For me, Evans waterless seems to work best with my priority being not boiling over when I get hot so I keep heated bars and keep enough coolant in the bike at all times to avoid damage from overheating due to boiling out too much coolant.
 
Another vote for Evans. Ive been using it for several years in several bikes. It has eliminated my boil over issues on all the bikes. Still requires room in rad for thermal expansion, top of fins works. Never have to add.
 
@Chadx & @dooman92
Take it from the pioneer engineer himself- watt man, this is directly from the research articles & info on his website:

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If your getting too hot, time to pull over and cool down maybe? At a certain temp you will begin to damage electronic sensors in your engine so you dont want to just keep raising your boiling temp to extremes.... Instead find the cause of why it's getting so hot, and work out a solution.

But to give you a slight bump in boiling temp without having to go with an option that has poor thermal properties- get a higher pressure rad cap. Thats why my coolant bottles are 2.0 bar.

If you ever do boil over and want to prevent fluid loss, and want to have a full coolant tank/ rads at the end of the day, heres the best and cheapest coolant catch can for dirt bikes I have seen to date: DIY coolant catch can

With the proper setup, there is no cons to traditional coolant.

Cons to evans:
- it's proprietary so in case of some hose failure or something happening out in the mountains and it leaks out, you can't top off with water or snow to make it back down.

- it raises operating temp, when the goal was to lower temp... it just solves the boiling over issue with a bandaid / duct tape kind of fix..

- Because of its poorer thermal properties (does not suck away heat as fast) waterless coolant does make an engine run hotter at the cylinder heads and creates hotter hot spots throughout the heads. This can cause some serious damage in high performance engines.

Im sure theres more cons you can find on google.
 
Would you fill up with 100% normal green antifreeze (ethylene glycol) or would you dilute it to 50/50 water mix? Why?

One of these has higher heat-transfer capabilities and one doesn’t boil over until 387 degrees.

From a “heat exchanger” perspective you need to a larger system or larger “radiator” to deal with the worse thermal capacity and conductivity of the less efficient fluid.
 
@XRTEngineered
Thanks for the comments. I'm definitely not advocating using Evans and to keep on riding even when you are overheating. It's common sense (I hope) that one should avoid overheating your engine at all much less intentionally run it long periods of time in an overheated state. I do watch my temps and pull over, or otherwise cool it off, when temps overheated. It's only that if I happen to not catch it, Evan Waterless doesn't boil off. You are correct that a higher pressure cap and/or catch are also viable solutions if using standard coolants when one happens to not notice temps overheating.

I agree it's meant to be used pure, however, you can top off with standard coolant/water/snow perfectly safely in a situation where you have no other choice. You'll just have to drain, prep, and refill with pure Evans when you get back home. An inconvenience and also a minor expense, but if you are in a situation where you need to use other coolants/water, you can. Nothing bad will happen as far as compatibility and you can even continue to use it mixes. It will just behave like standard coolant and vaporize/pressurize if there is more than about 3% water in your system. I'd argue that you typically won't have standard coolant available on the mountain either and, if you add snow, water from your water jug, etc. you are going to be in the same situation when you get home; you'll have to drain and re-fill to get your water/coolant ratio correct again and to get out any contaminants, hard (non-distilled) water that you sourced on the mountain.

Your points about Evan Waterless thermal properties are noted and I was aware of those, but didn't see it as much of a con for snowbike use. We are using thermostats and temp gauges and are typically running in a cold environment rather than hot summertime trail/motocross use. If a particular engine's cooling system was always unable to keep that engine from overheating, or always right on the verge of overheating, during it's typical use, I agree that Evans thermal properties may be a con in that situation. In our case, we have a temp gauge keeping us up to date on engine temp and a thermostat that is opening and closing to control temps. Part of the reason I switched to a tunnel cooler was to give even more cooling overhead and so the thermostat could open and close as needed. Agreed there could be localized hot spots in the head, but we have that when standard coolant is vapor rather than liquid on those same hot spots since vapor has poor heat exchange compared to liquid.

@everytime5.9
Agreed that poorer thermal properties in a hot environment very well could require a larger radiator/heat exchanger, higher flow rate over the heat exchanger, etc. However, snowbikes are ridden in a much cooler environment than dirtbikes and so we have an environmental temperature advantage compared to riding in 100+ degree heat. I have no idea the calculations, but I think it's fair to say that -10F air hitting a radiator will pull much more heat out of a cooling system than 100F air hitting the same radiator. There is more to it than radiator size; air temps, air speed over a radiator (fan or riding speed) and rpm (which increases waterpump and coolant circulation speeds) play as much a part. And, since this particular thread has us swapping to tunnel coolers, we effectively are enlarging our heat exchanger capability greatly over stock radiators. Then, are actively using a device to reduce that heat exchange (a thermostat). In the big picture of cooling an engine, the only time reduced heat exchange becomes an issue is if one's cooling system is flowing at 100% capacity (no thermostat or thermostat open) in your normal operating environment but your engine is in a constant state of overheating (single track riding in high temps is a good example). In that case, heat exchange would need to be increased which there are many ways to do: add a fan to a radiator to increase airflow, increase radiator size or better design, or, like you said, ensure you are using a coolant with better thermal properties.


In summary, I see Evans Waterless and standard coolant as two ways to skin the same cat. Standard coolant can be used with higher pressure caps/systems and coolant overflow bottles. Evans boils at a higher temp. Neither should intentionally or regularly be run overheated. Evans has poorer thermal properties so if the engine being cooled is constantly overheating, one will need to make a change to exchange more heat (enlarge heat exchangers, make existing heat exchangers more effective (exposure to more or cooler air/water/snow), or switch to a coolant with better thermal properties).

In my particular case, I'm running perfect temps in the powder because the thermostat opens and closes as needed. My heat exchanger and it's environment (in this case, tunnel cooler blasted with snow) offers more than enough heat exchange. I do have to solve my hotter-than-desired temps on the trail, but I knew I'd have to do that when I did a tunnel cooler and radiator delete. If I'd retained on radiator, I'd be fine on the trail. I'd intended to a ski scratcher, but ran into a snag with ski shape and ski-scratcher compatibility so I'll be resolving with rail mounted scratchers. Once scratcher solution is implemented, the needed heat exchange will be more than adequate on the trails as well and thermostat will open and close to control temps.
So based on the real world engine temp data for my particular build, there are no cons to Evans. I fully agree there are plenty of engine, environments and use cases where using Evans could be challenging, but not seeing any for a situation where a thermostat is regularly closing because the heat exchange is adequate to cool the engine in question.

This is a great conversation! Fun stuff to think through.
 
As i posted earlier on here, I find my ktm500 heating up trail riding back to the truck, issue is not about snow kicking on the cooler, its lack of engine rpm circulating the coolant, so next time it starts to heat, try kicking it the ass, drop a gear and tear down the trail for 100 yards, temps drop right now on my 500 when I do that.
 
As i posted earlier on here, I find my ktm500 heating up trail riding back to the truck, issue is not about snow kicking on the cooler, its lack of engine rpm circulating the coolant, so next time it starts to heat, try kicking it the ass, drop a gear and tear down the trail for 100 yards, temps drop right now on my 500 when I do that.

Agreed. My experience was the same when I had radiators (and will presumably be the same with tunnel cooler), and applied to both standard coolant and Evan Waterless; A bit extra rpm moves more coolant. Since I'm on a close ratio bike, high rpm is a given most of the time when cruising the trail, but in the slower twisty trail sections, if I'm getting lazy and staying on one gear rather than shifting, rpms can get low.
 
@XRTEngineered
Thanks for the comments. I'm definitely not advocating using Evans and to keep on riding even when you are overheating. It's common sense (I hope) that one should avoid overheating your engine at all much less intentionally run it long periods of time in an overheated state. I do watch my...................................
You do have some very good and valid points made there, and yes I agree with you the debate is "two ways to skin the same cat" or more so like the "which engine oil is the best" debate.
You really can't go wrong with using either, much of it comes down to preference.
My preference is increase system pressure to raise boiling pressure without losing thermal conductivity efficiency.

Oh so you can mix evans with water. I never thought into it of why and figured it just had some chemical incompatibility.
 
Just some feedback. Thanks for a great product. Before I knew you made the extensions to move the cooler back on the new ARO, I bought the cooler without extensions and mounted it clear forward as far as It could go. Zero problems with keeping temp up in powder and rail mounted scratchers keep it cool on the trail. We'll see what happens when spring temps warm up and I have to ride any ice roads...
 
Been running tunnel coolers for years .. just picked up and couple from you and man they are very nice pieces. They get the job done! On my set up I run a ball valve with 1 radiator . And zero issues all season . Great product!


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I went to a local industrial plastics supplier and told them what I was doing and they sold me this. They said it could handle getting hot. To be honest I cant even remember what it was called. It was pretty expensive, because it can handle a high heat without deforming.

I also used it as a skid plate material and when it touches the exhaust it deforms where it contacts, but it doesn't completely melt or catch fire.
 
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