Cold Tecate

[Tecate250]

Hey guys. Had this problem years ago but went away. lol. I had lots of problems in the past with my carb freezeing up while rideing in cold weather. I installed a lightly used original 83 kx 250 with stock piston and rings. Never had a problem running it in 3 years. I should have rebuilt it befor it was too late but no.1 more ride. I have a tecate 4 stator/cdi. Original kx 250 83 carb. Only carb I have ever used. And V force reeds. Dg silencer and bassani head pipe. Bike worked amazing.Anyway my nika plated cylinder is toast. So I installed one of my tecate cylinders. Max bore steel sleeve. And sure enough its winter. And worked great till one day I was out and a friend broke his 450 yfz. So we waited for a tow. About 1 hour later. And now my carb is freezing up. Thought it was water in my gas. Nope. Bad plug? nope. Timming off?Kicking it over broke my kick starter and is hard on my ankel. Nope. Moved my needle? Nope. Doing this I noticed alot of ice inside my carb.Thought water was getting in around my cable? nope. I put new crank bearings in it when I put the tecate cylinder on the kx. Could the Tecate jug have way different jetting then the kx? Ive never re jetted befor for winter rideing. Please I need help.

[El Camexican]

Carbureted cars used a pipe between the exhaust manifold and the air cleaner to prevent this. The ice is caused by the air being condensed as it flows into the carb throat. I’m going to assume the temp in your area is right around 0C and that it is very humid when this happens?

We used to dump a ½ Liter of Methyl Hydrate into 20 Liters of fuel when we rode our sleds in high humidity conditions, but the carbs were under the hood of the sled where the engine heat was keeping the carbs warm. Short of rigging up a duct to feed air from your rad into your air box I don’t know what you can do to solve this. Do you have a thermostat? Putting slightly larger jets in won’t hurt anything, but if that ice starts blocking fuel flow you could have a problem.

[Tecate250]

Well it can actually freeze up at 2C. Now the Kehin carb thats on the kx. Are all kehin jets the same? I have not seen another motor with a similar carb. Could there be another issue?

[El Camexican]

Well it can actually freeze up at 2C. Now the Kehin carb thats on the kx. Are all kehin jets the same? I have not seen another motor with a similar carb. Could there be another issue?

Freezing in the carb when the ambient temperature is 2C makes sense. The moisture in the air freezes when it rushes through the throat of the carb. If it was colder outside there would be less water in the air and if it was a little warmer the temp inside your carb would stay above zero. Either way, problem solved.

Not sure what you are asking about the jets, jetting is not causing the icing, but as far as I know the mains and slow jets for the PJ and PWK carbs are the same. Not sure about the PE, or PWM.

If the icing is occurring past the main jet then adding Methyl Hydrate should stop the icing, but I’m a little leery to suggest using it as it will create a slightly leaner condition and you aren’t up on jetting.. Let me ask you this. Have you ridden the trike at say -15C without issue? If so then adding 5% Methyl Hydrate to your fuel at 2C should be fine. Canadian Tire should have a good stock on hand. As it atomizes in the carb throat with the incoming air it should prevent the ice from forming. The fuel at the local pump should also have some additives for this if this is typical weather for your area, what are you using for fuel?

[Tecate250]

El Camexican Thank you so much. I remember a long time ago this post wouldnt have less then 20 post on it with helpfull infomation. ANd you took the words right out of my mouth with it never really acted up when it was really cold. Now come the funny part. While haveing some beers last night i had a brain fart. IS there a way I can route another lower rad hose.(the one that goes from rad to water pump) from the top water pump nipple fitting thing, around the carb and back to the removable cylinder fitting. Ive even thought of flipping this fitting to ensure lots of room in this are. But would adding more coolant hose make the engine to run cold or anything.

Again El Camexican thak you.

[El Camexican]

I was thinking along the same lines with my comment about running a duct from the rad to the air box. Honestly I don’t think a rad hose passing around the carb, or through the air-box will radiate enough heat to the incoming air to make a difference, but warm air routed from the exit side of the rad and directly into the air box would. Anyway, semi-crazy ideas aside, why not just try the Methyl Hydrate? We ran our sleds and cars with it all the time when conditions were right for icing up the carbs. The only thing you have to remember is that Methyl Hydrate is hygroscopic (it sucks water out of the air like brake fluid) so if you don’t run your tank dry you end up with water in it at some point and the only cure aside from using it up, or dumping it out is to add more Methyl Hydrate to emulsify the water in the gas and burn it. Not a big problem, just something to keep in mind if you don't run the tank dry.

Try it, 5% only, I’m sure you’ll be happy with the results.

PS. This is what a properly set up cold Tecate should look like
182965

[badass350x]

Hell I'm just thinking cold beer!!!! Had to throw it out there..

[El Camexican]

I only looked at this thread because I was expecting to see something like this. Needless to say I was quite disappointed!
182981

[Tecate250]

Hehehe. Sorry to "HAVE WAISTED YOUR TIME" El Camexican I never had "Cold Tecate Beer before" Anyway. I tried the gas line antifreeze and it worked a bit but later froze up again. I had a post about this befor and semi-crazy ideas I made 2 green shrouds to reflect hot air from my head down. It looked gay and didnt do nothing. So im trying out a head bib. lol yes a bib. Im useing an old hood from a winter jacket that is nylon. Hopeing it will disapate water and keep warm air around my carb. Ill post pics later when i start to buils it.

Oh and there is nothing like a Cold Alexander Keiths beer. Since 1820

[El Camexican]

Hehehe. Sorry to "HAVE WAISTED YOUR TIME" El Camexican I never had "Cold Tecate Beer before" Anyway. I tried the gas line antifreeze and it worked a bit but later froze up again. I had a post about this befor and semi-crazy ideas I made 2 green shrouds to reflect hot air from my head down. It looked gay and didnt do nothing. So im trying out a head bib. lol yes a bib. Im useing an old hood from a winter jacket that is nylon. Hopeing it will disapate water and keep warm air around my carb. Ill post pics later when i start to buils it.

Oh and there is nothing like a Cold Alexander Keiths beer. Since 1820

Is it still 2C up there? Maybe you need to just stay home and drink beer on the days that the temps are between -2 and +2 and ride on the other days. Anyway, anything that can transmite heat from your engine to your carb can't hurt, but don't end up burning your trike! Post pics, even if it does look queer.

[tri again]

Don't small airplanes get (or at least warn of ) carb ice at 60 * F?
Some flapper directs exhaust heat towards the carb somehow for landings and other tricky situations.

[Tecate250]

well 2 in the morning came fast. Got my "Sooky Blanket" on the tecate. Insert jokes here. Didnt have my camera but it came out quite well.
60 O wow oh wait F.