2T keeping the pipe hot
- Thread starter kinneyt
- Start date
3 years on 2 different 2T's here. (YZ 300 and XC 300) Never have had a real issue with pipe temps, maybe on real deep days, however I have noticed just running a carbon pipe guard seems to help with running more consistent.
I don't run any guard at all. Going downhill for a long time seems to cool the pipe but it only takes a second to heat back up and not worth worrying about it. My buddy has a 250sx that has never been in dirt and the pipe is blue well into the center of the bulge, it has no trouble getting hot!
When it comes to building power it doesn't take much to rob from a 2 stroke pipe and a cold pipe is it and hot spots will keep it running but it's not doing what it's claimed to because it was also designed to run as cool as possible .
4 stroke exhausts rely on some kind of back pressure and run quite well with minimal but every bend , swell , necked down part of a 2 stroke pipe has a purpose threw out the entire power band .
Even a 2 stroke sled will fall flat on it's face ripping across a lake if an uninsulated pipe fails to keep it's heat , not to mention the amount of fuel wasted .
One would think that with limited Hp that you would do all that you can to keep the ponies up and some kind of consistent fuel consumption .
Wrapping is easy and should be recommended if your serious about riding . Someone will come out with insulated clam shells some time one would think , opportunity knocking .
4 stroke exhausts rely on some kind of back pressure and run quite well with minimal but every bend , swell , necked down part of a 2 stroke pipe has a purpose threw out the entire power band .
Even a 2 stroke sled will fall flat on it's face ripping across a lake if an uninsulated pipe fails to keep it's heat , not to mention the amount of fuel wasted .
One would think that with limited Hp that you would do all that you can to keep the ponies up and some kind of consistent fuel consumption .
Wrapping is easy and should be recommended if your serious about riding . Someone will come out with insulated clam shells some time one would think , opportunity knocking .
I ride a 300 EXC TPI and only use a carbon pipe guard that helps a lot. Though not many days that the bike sits so low in the snow that the pow gets to the pipe constantly, so if you ride in dry pow or very deep pow you might have to wrap the pipe also.
Rob
Rob
Im supprised so many snow bike riders dont wrap exhaust band around the pipe. You will loose hp when that pipe gets cold in the snow, but the exhaust bandage will help. We always use exhaust bandage when we ride on the ice with studded tires!
And if you are really unlucky and get some snow on the extremey warm exhaust side of the cylinder , it could crack.
I recomment exhaust bandage!
And if you are really unlucky and get some snow on the extremey warm exhaust side of the cylinder , it could crack.
I recomment exhaust bandage!
I'm curious who has actually noticed a difference and has tried it both ways? I'm not arguing the science but have tried it with wraps, carbon, and full frontal skid plate deflectors and never said wow that's better other than the 1 Mississippi delay going down hill the non wrapped pipes seem fine. In theory a header wrap might be worse cause it acts like a wet sponge against the pipe which is probably why sleds have a cover over the wrap. Either way engine shroud, thermostat,proper jetting, high compression and porting makes way more noticeable improvement so don't waste much time worrying about your pipe temp until you have nothing else to fiddle with.
Header wrap actually extends the longevity of a pipe or header if a little maintenance is taken .
I doubt if anyone is gonna have rave reviews over wrapping besides being a pain but for the hardcore it makes a difference and extends maintenance schedules . Most riders won't even go rider at ten degrees or below and that's when a two stroke starts building power . There's a lot more than just building power , look up cold seizure .
It just occured to me that some bikers that have gotten into the snow bike probably don't have the experience of how different a two stroke runs in winter conditions . Not digging on anyone , thermo bob and programs have helped and those are even newer . Sleds have been doing the programs since the late 80's and the thermo Ski-Doo gets credit for . The first wrapped pipe I seen was at a poker run in the 70s , that's when prototypes dominated . Now if sleds could only make thier riding gear as good as the bikes . Just babbling , snows coming 
I doubt if anyone is gonna have rave reviews over wrapping besides being a pain but for the hardcore it makes a difference and extends maintenance schedules . Most riders won't even go rider at ten degrees or below and that's when a two stroke starts building power . There's a lot more than just building power , look up cold seizure .
It just occured to me that some bikers that have gotten into the snow bike probably don't have the experience of how different a two stroke runs in winter conditions . Not digging on anyone , thermo bob and programs have helped and those are even newer . Sleds have been doing the programs since the late 80's and the thermo Ski-Doo gets credit for . The first wrapped pipe I seen was at a poker run in the 70s , that's when prototypes dominated . Now if sleds could only make thier riding gear as good as the bikes . Just babbling , snows coming
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We have ran cr500s, 2 yz250s (still run one) and a panthera in Utah. So we don’t get crazy cold temps but we do get deep snow. I am with Eric on this one. We enclose the engines, carb heat, tunnel cooler etc but the pipe is out there is the wild. Combined about 500 engine hours without issue (compared to the 5 million hours Eric has … no joke) Warming it up right is important. To be the power delivery changes if it’s really cold dipping in the snow but overall not worth the trouble of wrapping. Now if you could clamp the the pipe with a cover that would be interesting.
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Cold snow hitting the pipe on my old snowhawk made it run pretty bad, my 2 stroke 250 and 300 snowbikes not so much.
P
portgrinder
Well-known member
Wrap not required. Tested in feild and dyno with pipe in an ice bath.
Carbed bikes. Tpi maybe different
Carbed bikes. Tpi maybe different
I THINK (don't take that for granted) is that CVT engines usually have tuned pipe that are actually tuned for a narrower power range than geared vehicle. And the little reduction in power from cold pipe means lower RPM with the CVT, magnifying the seat of the pants effect. On a dirt bike, you're a small clutch slip away from getting back to full power.
That’s my understanding exactly.
Yes plus the port timing is way higher (even pipier than a 125) combined with the fact that a cvt is torque sensing so it will start to upshift if the engine losses power for any reason - like a cold pipe or elevation gain. Pipe temp is important on sleds but not bikes. The factory 440 race sleds were so pipey they had a handle bar switch that retarded ignition during the launch to get the pipe hot off the line. I rode one in the mountains for a season and was changing the clutch clickers twice each ride during elevation changes.
Those 440 race motors had a razor thin powerband.
Sea level drag races though they were smoking 600’s in the 1/8th mile.
Pro found carbon worx has sold some carbo clamshells
