Anyone consider putting a valve in to cut flow off to one radiator?
Ideal 4 stroke engine temperature?
- Thread starter needpowder
- Start date
they are plumbed in series, you would have to redo everything and then water would take the easiest path when valve is open anyways
I just took off one radiator and replaced the remaining one with a mylars oversized unit and a fan on a switch. Simple easy fix and I dont have to mess with covers and all that crap. Stays under 230 even on hot spring days.
interesting subject, and one I'm currently struggling with. I am running a Thermo-bob 3 and 190* stat w/ a full SXS engine cover and I've STILL got motor temp issues. I can't get the motor to ever see more than 135 even on the trail. I thought I had a bad stat - so I swapped the stat out for a new one - still have issues. Checked all my plumbing and everything is right. it basically runs like there no stat. when I hit the deep pow temps drop to 90 or even a touch less. I changed out my temp gauge, no change. Thought it might be temp sensor, but nope - it reads pretty accurately as well (garage temp is 45 in the winter, bike been sitting for days, temp gauge reads 45 as well).
Any ideas???
Any ideas???
I used the pst jacket... Thermo Bob 170 .. still waiting for a skid plate... I ran a constant 135 to 180... In the powder around 145... It was close to 4 feet of bottomless... Now I am sure with the turbo my engine produces more heat... But I am using a tunnel cooler and one radiator. It's a KTM sxf
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Cover your radiators. Especially if your bypass still feeds into the radiator rather than directly back down into your coolant intake. Even if it does...cover your radiators.
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Thanks!
I'm gonna try blocking the rads and hope it does the trick.
My bypass line runs right into the left radiator output per the directions... so, i'm baffled why my bike never heats up. its like the thermostat is always stuck open...
It does seem strange that the bikes don't heat up with the thermostat. That's just the way it is though. Dooman explained what I think is happening pretty well in post number 12. Build some radiator covers, but think about insulating your engine with foam and getting the PST engine jacket or similar. The engine covers you have seem like they would help but without a fully enclosed engine I just don't think you're gonna be able to keep your temperatures up in the really deep and cold.
Mr quick, some old radiant heat systems (cast iron radiators) had no mechanical means to pump or circulate the heated liquid. They worked based on convection just like your radiators. In those systems the warm liquid rose in one end of the radiator and gave up its heat and the cooled liquid fell to the boiler. Convection is taking place in both your radiators extracting heat from the engine. Gotta get those radiators warm with or without a stat.
By the way, I ran the SXS cover on my KTM 525 along with my home-made radiator guards and stock KTM thermostat and my temps were mostly fine. No foam between guard and engine. No shield at the back of the engine. And I had a wrapped pipe (which might have allowed less heat rather than more, but may have also avoided the steam flowing back and freezing on the carb and other bits). I also had an oversized gas tank on the bike so that hung lower than a stock tank which protected the engine and carb a bit more than the stock tank. And I did not run radiator shrouds. Just radiator guards and hung the radiator covers on the outside of the radiator guards.
Change one thing at a time and test but I think you'll find a major benefit in covering those radiators.
I made my radiator guards out of plastic (see my post further up for the material thread to which I linked). I intentionally had them hang on the outside (leading surface) of the radiator guard rather than inside (between the radiator guard and radiator) because I didn't like the way the radiator guard would get totally caked with snow and restrict flow if I needed it for a long trail ride back on a warmer day. But hanging it between would likely be nearly as good.
The alternative that I like the ideal of is a fabric cover with elastic. Really fast off and on and easier to store (keep in mind, with the hard plastic covers, you'll need to store them someplace when they are off. So in your backpack or tunnel bag). They make prefilter material ones that look slick. They would block all the power from hitting and cooling though they would still flow some air. I think the powder is what really cools off the radiators and not the air, so they might be worth a try. Or make a homemade set out of some type of material that snow won't stick to but also won't melt at radiator temps. Would be easy to make. Shape your fabric and sew in elastic. Really fast off and on and storage. (shove them in a plastic bag, before putting them in your pack, if they are a little snow and ice covered).
I don't have any photos handy of the covers on the bike, but here is a picture of them, an the SXS shroud, not on the bike. I cut them about 2 or 3" taller than I needed and then used a heat gun to fold over the top 2 - 3". It was as tight of a fold as I could get it and then, to install, I'd just slide that tab down between the radiator guard and radiator. While it sounds like they would easily come off, they never did nor came close. They sat in there really well. If anyone is interested, I can take more pictures, in the next week or so, of them installed and from various angles since the below doesn't really show the angles good.
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I'm not worried at all with temps 130+ on my YZ. Why? Because I ran the temp gauge all summer long and my bike runs between 135-185. So if I run 135 in the summer with no issues, why worry about it in the winter?
Thermobob, pst engine jacket - going to make myself some radiator covers as well but it's not a big priority at this point.
First ride I was 120-150 in deep powder. Max temp was 167. Changed oil at home and it was perfect.
Thermobob, pst engine jacket - going to make myself some radiator covers as well but it's not a big priority at this point.
First ride I was 120-150 in deep powder. Max temp was 167. Changed oil at home and it was perfect.
update: I built some easily removable covers. They made a big difference! I'm not building any oil any more. yeah! I also found out that my temp sensor itself is bad. I knows the guards helped, because my bike rarely dies anymore. I also did find that my original stat was stuck open. Interesting for sure, bout 3mm, which is still significant. I'm going to build a shield at the back of the motor too and see if it helps. We've had insane low temps for WA lately, so i'm imagining things will improve on there own here soon, but i'll tell yah - i'm sick of 2 degree mornings at the truck, and negative temps up on the mountains. Probably normal for a lot of you, but not for us!
