300 TPI

[boondocker99]

What's everyone done on their 300 TPI bikes for optimal engine performance in the cold (0f) with fluffy snow. I've read a lot of comments that 300 TPIs don't need engine blankets or pipe wraps but my first ride on my 300 TPI it did not run very well (0f). One other ride it was about 15f and seemed to run better than at 0f. It seems to really struggle/stumble in the low-mid range area, really bad at times. Once it gets into higher RPMs it would run great. I have a thermobob and a air filter pre-filter otherwise 100% stock engine wise.

Considering the following but would like feedback
1. SXS engine guard - should help maintain engine temps
2. pipe wrap with high temp silicone (soaked)
3. Rad block or bypass - Is a block good enough? Would rather not do the by-pass if a block/cover will do similar

Anything else I should consider? I do plan on adding a RK Tek head to improve overall performance.

Please no comments about 450s. I DON'T want a 4 stroke at this time.

For the record I have a 2019 Husqvarna TE300i w/CMX 129.

 

[boondocker99]

I also have carbon fiber exhaust guard. Can't seem to edit the original post...

 

[JimBridger]

My buddies 20 300tx, runs best around 180*f. He made a cover for the engine, and also completely wrapped his pipe to keep it hot. He is running an rktek head and a ktm fmf fatty. The more consistent he can keep pipe and coolant temps, the better it runs.

 

[wwillf01]

Yep for me even on wheels I find if my pipe gets cold going through snow burns it bogs on the bottom end... now I Installed a get and it solved a lot of those issues. Dont know with snow and the kit but that has to be magnified...

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[portgrinder]

get a temp gauge and live by it. you want it as close to the head or in the head if possible. a great spot is to drill and tap the air bleed screw in the top of the head to thread it in there. you want to run around 120F. 180 is too hot. 120 is not tough to achieve. the TE should have a t stat between the head and the rads from factory. if you make a little cover that covers most of your cylinder that will be plenty. you can buy a fancy one of make one yourself for about $20.

don't block your rads. if youre not getting temp, your t stat is closed anyway and flow thru the rads is minimal. your temp is being lost from snow packing against the cylinder. if you block your rads, then when you actually need them, they wont work and you will overheat.

don't wrap your pipe. in my experience it does nothing beneficial, and it steams all the time which is super annoying.

if its running like junk, 75% chance its intake related. cut the bottom of your airbox out so snow can get out of there. if that's not it, then the motor is probably stone cold. like below 50F. dont run it till its at least at 80F

 

[wwillf01]

get a temp gauge and live by it. you want it as close to the head or in the head if possible. a great spot is to drill and tap the air bleed screw in the top of the head to thread it in there. you want to run around 120F. 180 is too hot. 120 is not tough to achieve. the TE should have a t stat between the head and the rads from factory. if you make a little cover that covers most of your cylinder that will be plenty. you can buy a fancy one of make one yourself for about $20.

don't block your rads. if youre not getting temp, your t stat is closed anyway and flow thru the rads is minimal. your temp is being lost from snow packing against the cylinder. if you block your rads, then when you actually need them, they wont work and you will overheat.

don't wrap your pipe. in my experience it does nothing beneficial, and it steams all the time which is super annoying.

if its running like junk, 75% chance its intake related. cut the bottom of your airbox out so snow can get out of there. if that's not it, then the motor is probably stone cold. like below 50F. dont run it till its at least at 80F

I find the tpi I have is much more picky about being cold then a carby... have you found different? Also seems to be happier at 180 than 130 like a carby? On the te150i we have if we have been in 40 degree weather and a bunch of mud gets packed around the pipe (one of those big protective metal ones that go under the pipe) it starts having issues bogging... that's our experience with wheels though have not put tracks on the 300 or 150...

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[JimBridger]

get a temp gauge and live by it. you want it as close to the head or in the head if possible. a great spot is to drill and tap the air bleed screw in the top of the head to thread it in there. you want to run around 120F. 180 is too hot. 120 is not tough to achieve. the TE should have a t stat between the head and the rads from factory. if you make a little cover that covers most of your cylinder that will be plenty. you can buy a fancy one of make one yourself for about $20.

don't block your rads. if youre not getting temp, your t stat is closed anyway and flow thru the rads is minimal. your temp is being lost from snow packing against the cylinder. if you block your rads, then when you actually need them, they wont work and you will overheat.

don't wrap your pipe. in my experience it does nothing beneficial, and it steams all the time which is super annoying.

if its running like junk, 75% chance its intake related. cut the bottom of your airbox out so snow can get out of there. if that's not it, then the motor is probably stone cold. like below 50F. dont run it till its at least at 80F

Thermostat in the tpi bikes are 158*F. So I see that as the low side of the operating temperature. 160-190 is where the mapping makes the best power on these tpi bikes.

Anything below 160 is going to run rich just like the FI 4 stroke.

I totally agree with you about temps if we are talking carbed bikes.

 

[boondocker99]

get a temp gauge and live by it. you want it as close to the head or in the head if possible. a great spot is to drill and tap the air bleed screw in the top of the head to thread it in there. you want to run around 120F. 180 is too hot. 120 is not tough to achieve. the TE should have a t stat between the head and the rads from factory. if you make a little cover that covers most of your cylinder that will be plenty. you can buy a fancy one of make one yourself for about $20.

don't block your rads. if youre not getting temp, your t stat is closed anyway and flow thru the rads is minimal. your temp is being lost from snow packing against the cylinder. if you block your rads, then when you actually need them, they wont work and you will overheat.

don't wrap your pipe. in my experience it does nothing beneficial, and it steams all the time which is super annoying.

if its running like junk, 75% chance its intake related. cut the bottom of your airbox out so snow can get out of there. if that's not it, then the motor is probably stone cold. like below 50F. dont run it till its at least at 80F

I've heard warpping the pipe can make a big difference and if you do it right (DEI silicon spray - soak and cure) it won't steam at all.

 

[boondocker99]

Thermostat in the tpi bikes are 158*F. So I see that as the low side of the operating temperature. 160-190 is where the mapping makes the best power on these tpi bikes.

Anything below 160 is going to run rich just like the FI 4 stroke.

I totally agree with you about temps if we are talking carbed bikes.

It's my understanding from multiple sources that the stock TPI thermostat is only 90*f and why I upgraded to a Thermobob. I believe the Thermobob I got flows at 131*f.

 

[boondocker99]

It's my understanding from multiple sources that the stock TPI thermostat is only 90*f and why I upgraded to a Thermobob. I believe the Thermobob I got flows at 131*f.

Well looks like I got some bad info. Confirmed the stock thermostat flows at 158*f and going back to that. Pretty sure the thermobob I have had a lower temp flow rate and part of my problem! Thanks for the feedback!

 

[GlennRMK]

Get a 160 ish t stat for the thermobob. I don't think the stock t stat has a bypass which is key for snowbiking IMO

 

[boondocker99]

Get a 160 ish t stat for the thermobob. I don't think the stock t stat has a bypass which is key for snowbiking IMO

What do you mean? Doesn't a thermostat always have a bypass? What exactly does the bypass do?

 

[JimBridger]

If you just get a different stat for the thermobob, you have a nice port for a temp gauge still.

Keep us updated.

 

[boondocker99]

If you just get a different stat for the thermobob, you have a nice port for a temp gauge still.

Keep us updated.

Problem is the Thermobob is that it's VERY tight fit and don't think it will work with a larger tank.

 

[portgrinder]

my experience is on a carb kx5 and a carb tx300.

coolant that hot in a 2 stroke is downright silly. its probably an emmisions thing.

I would be running mine in the 120 range and making a little resistor to make the coolant sensor think its that warm. super simple. have done it lots.

you need to watch with the pipe wrap too...a lot of time it will wreck your pipe unless its stainless. cant get the water out and it degrades over time.

 

[wwillf01]

my experience is on a carb kx5 and a carb tx300.

coolant that hot in a 2 stroke is downright silly. its probably an emmisions thing.

I would be running mine in the 120 range and making a little resistor to make the coolant sensor think its that warm. super simple. have done it lots.

you need to watch with the pipe wrap too...a lot of time it will wreck your pipe unless its stainless. cant get the water out and it degrades over time.

Could be silly but the map on these things is dependent on being warm unfortunately..

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[boondocker99]

my experience is on a carb kx5 and a carb tx300.

coolant that hot in a 2 stroke is downright silly. its probably an emmisions thing.

I would be running mine in the 120 range and making a little resistor to make the coolant sensor think its that warm. super simple. have done it lots.

you need to watch with the pipe wrap too...a lot of time it will wreck your pipe unless its stainless. cant get the water out and it degrades over time.

Seems silly to mess with the computer. If KTM thinks it needs to be >158*f there must be a good reason for it. As for the pipe who really cares, they are cheap to replace!

 

[wwillf01]

I am sure its emissions.. when I added the get ecu it was not picky anymore... it's just mapping...

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[eric82930]

Seems silly to mess with the computer. If KTM thinks it needs to be >158*f there must be a good reason for it. As for the pipe who really cares, they are cheap to replace!

The "good reason" has nothing to do with performance. They will get better but right now it's a joke. It's still an open loop ecu. no real compensation is being done other than it creates leaner than sea level conditions for elevation and temp. But it's already too lean for the epa. All the issues they are having are the same as ones from the miss jetted carbs from the factory just that the carbs ran better because they didn't get leaner at altitude. Sorry for my obvious tpi pessimism...

 

[boondocker99]

The "good reason" has nothing to do with performance. They will get better but right now it's a joke. It's still an open loop ecu. no real compensation is being done other than it creates leaner than sea level conditions for elevation and temp. But it's already too lean for the epa. All the issues they are having are the same as ones from the miss jetted carbs from the factory just that the carbs ran better because they didn't get leaner at altitude. Sorry for my obvious tpi pessimism...

How does elevation make it leaner? Air is thinner the higher you go and the ecu also adjusts for elevation. I'm also not sure what all these "issues" you speak of. My 19 has been flawless on dirt and just need to get temps controlled for snow...