Snowbike Temps - What Are you Seeing ?

summitboy · Dec 22, 2014

I thought i would start a new thread for seeing what guys are seeing as far as bike temps are concerned. Now with the Avid stats and the Thermobob stats we should see some better temps on various setups. Please list your bike and cooling setup and some temps you see thus far. Will be interesting for sure.

List the following:

Bike and Carb/EFI
Tstat
Carb heater (or not)
Trail Temps
Deep snow temps

Here is what i ran last year:

CR500 Millar TWIRP porting
Smartcarb 38mm
No carb heater
No stat
190-215F on trail
90-110F deep snow
Two instances of slide sticking in 12 rides

List away !

the gman · Dec 22, 2014

13 ktm 300, pipe and head, Sx box, avid thermostat and carb heater,40 smart carb, trail riding 130, right up against thermostat, deep powder below 100 degrees. Carb completely covered in snow, need carb cover as had some slide sticking, running no filter, just timbersleds snow net.

summitboy · Dec 23, 2014

How much below 100F ? My Trailtech TTO measures 30F-500F. Is the Vapor different ?

Curious, are u running stock plug or hotter ?

andrew44 · Dec 23, 2014

14 ktm 450sxf. Thermostat 70degree. 158 on trails etc. depending on snow conditions off the trial I see anywhere from 130-175

summitboy · Dec 23, 2014

Curious why u run a 70C stat in a 4 stroke ? Would a 185F stat not be a better fit on that machine ? Which stat do u run ?

teal_210 · Dec 23, 2014

RMZ 450 with 70C stat. 120-200 degrees.

IMO 185 is the upper end of where you want to be, mine will start to spit coolant at 200.

The same bike during 90 degree temps during the summer time runs 150-160 with no stat.

Summitseeker · Dec 23, 2014

2014 KTM 300 with PWK 38mm stock carb
130 degree t-stat
Avid Carb Heater
Normal Trail Temps- have seen up to 240 degrees
Deep snow temps - have seen around 120-140 degrees on average (have not been in real deep snow yet)

Failed thermostat last weekend and hit 324 degrees on trail.

SteepNdeep450 · Dec 23, 2014

Think it'd be beneficial to know if they were running motor shed plates too?

Uncle si · Dec 23, 2014

Last spring I put a temperature sticker on my water jacket :

kx500
No thermostat
Carb no heat
250 + trail and deep snow!!!!!! :face-icon-small-sho

I put a cooler on it which helped. This year I am running a proper cooler, scratchers and 125deg. F thermostat. Temps seem to be in the acceptable range, but the sticker only reads as low as 149!

lacesout · Dec 23, 2014

2010 450sxf with carb heater and 190 thermostat kit. On the trails if i was going 10mph+ it would stay at 185-190 the entire time. Rarely would get over 210 no matter what i was doing. Unless I was going really slow waiting on someone or idling it to long it would not over heat. Spat out coolant once at 235.

JTAB · Dec 23, 2014

Aprilia SXV 550 140 to 210 no stat bone stock bike. Going to leave it alone seems good.

Stock 450 KTM SXF with KTM thermostat was running under 100 to 160. Will need ThermoBob to help, not happy with the low temps.

Boosted KTM 500 has ThermoBob and running two stock radiators this year will see how it works in a few days. Last year one radiator and a heat exchanger averaged 195-205.

the gman · Dec 23, 2014

My vapor only reads above 100.not like the good single gauge.

summitboy · Dec 23, 2014

Gman its interesting you only see 130F on the trail. Seems low to me. No cooler correct ? Will be neat to see other 300 temps in short order.

dooman92 · Dec 23, 2014

I have a 2010 husky te510 w/efi. I could not configure in a thermostat. I have engine shielding and I use a shroud or blanket type arrangement to cover the radiators. I have temp gauge in the line coming out of the pump to the radiators. I leave the rads covered until I see about 180 then open or cover as needed. I average about 190. The highest temp I have seen is 230 for about 30 seconds. In the deep powder I can leave the blanket mostly on. Anytime I am poking along slow, or a slow hard climb, I uncover completely and the fan comes on at about 208. I monitor the oil level closely and have had no gas in the oil. :face-icon-small-blu

mrquick68 · Dec 23, 2014

i think a good question here is what range should a 2 stroke snow bike be running at, and what range should a 4 stroke snow bike be running at. some base lines would be good. I've yet to have my fan turn on, but i've not really pushed the bike yet. This on a 14 Berg FE501.

Snwbiker · Dec 23, 2014

ktm 520 fully inclosed engine with speed way plastic and it runs right at 159F
on the trail or deep snow.
If you cant hold heat in the engine in the deep snow it maybe because you are turning your aluminum engine into a radiator.
Keeping the snow off the engine will let the thermostat do it job.

summitboy · Dec 23, 2014

I think a 2 stroke should run in that 100-130 range. 4 Stroke should be in the 160-180 range. Thats my opinion of course. I have run my 500 down to 80F no issues. I personally want to see cool as possible with enough heat for my carb heater. No more. That is between 90-110 i believe.

The only place where i see problems on bikes is if you were on a lake ice racing with major rad cooling. Thats where you would have to be careful. Snowbiking is big load and slow. The 2 strokes like the cold. 4 Strokes need temp to prevent oil fueling etc.

andrew44 · Dec 24, 2014

summitboy said:
Curious why u run a 70C stat in a 4 stroke ? Would a 185F stat not be a better fit on that machine ? Which stat do u run ?

IMO these four strokes run the best at 160F. anything above 190 is getting to hot.

summithd · Dec 24, 2014

14 Berg 501FE:

- Kevlar Engine Cover (can fold down on warmer days or take off easily)
- Thermo-Bob 170F degree t-stat

I have a closed cell foam pad that goes on the bottom of engine that i did not have on yesterday (between plastic skid plate & engine). That will be on this weekend.

Just got back from riding Cooke last night. Deep powder - constant snow/ice on radiators. This is the type of powder where the bike just chugs along. More of a sled turbo day in my opinion, but wanted to get some temp tests in on a day like this. Air temp was 10-15 degrees.

When I was on it full throttle for more than say 15-30 seconds, temps would climb to roughly 130-150...maybe slightly higher than that at times. Most of the time temps would be right around 100-120. Much too cold!

Trail temps were around 140-150.

****

Email I just sent to some buddies:

Here is the issue on deep days...

From Thermo-Bob documentation:
Note how even with the Thermo-Bob’s thermostat closed, that the coolant now has an unobstructed path to flow
at a high rate all the time, and now the thermostat only mixes in what cold coolant it needs. I've changed the
colors of the coolant to reflect what the test results show. Now coolant comes in pretty warm in the first place,
only gains a few degrees across the engine, and after leaving the engine and going down the bypass hose, only
mixes with a little cold coolant to get a small temperature drop in the coolant before going through the engine
another time

Note the highlighted red statement.

My take:
The coolant in the radiators is so cold from the constant snow/ice hitting the radiators all day, that the cold coolant is enough to bring down engine coolant temps even after cycling through the engine. The cold radiator coolant is never truly stopped from entering the coolant flowing stream! Yeah it is better than a stock setup, but isn't good enough when the ambient air temp is 10 or so and snow is hitting the radiators all day. Might have to block the left radiator to see what happens (in addition to putting the foam pad in).

portgrinder · Dec 24, 2014

'kx500af
Bored PWK, porting, pipe.
-5/16 line T'd out of my head wrapped around the carb, returning right infront of the water pump with a valve.
-KTM 55C T stat on one rad

On trail I close the carb heat and temps are in the 170-130 range depending on whats going on

In powder I open the carb line and temps are in the 70-100 range.

Works great. Whole airbox can be full of snow and the carb doesn't ice at all.

If my temps get too cold I just open my carb heat valve.

Snowbike Temps - What Are you Seeing ?

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Active member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Well-known member

Similar threads