I was out riding tonight pulling the kids around on a sled. Lots of low speed stuff. pulled into the garage and pulled the plug to see if it was running any different then summer time. My plug has always been black throught out the summer, Now it was cleaner and tan to brown. After the kids got cold and went in I opened it up a bit more and pulled it in again to check the plug. This time it was tan on one side and almost white on the other. Dont think I will test it at wide open. Ill just go to the dealer and get the 250 main jet. Definitely worth a quick check especially for the 2 strokers. GJ

 

Is it really that important to go down one jet size? I have had two-stroke quads for about 6 years now and have never done jetting changes...but now with the modded Scrambler, I want to be sure not to screw anything up!

Is it just one size? Is that a standard? Why is it that cold weather affects jetting?(lame question)

thanks

 

First things first. DO NOT GO DOWN, you need to go up, as in 250 to 260. The colder it gets, the leaner it will run and therefore a bigger jet is required to give it more gas.

I would take it up by .010 just to be sure, so that when you are riding in -30c you will not have any problems. Then again, its all relavant to how lean you are running now. You may be jetted for all out performance for summer riding and be just on the verge of being safe and may require .020 BIGGER if the temps get way down.

 

Do you do this every year, Snowride? I have never touched the jets on my Xplorer and it seemed to never have problems... Hmmm, the things we learn.

Well, it's off to the dealer this week to GO UP a size! If the quad is getting more gas, that means more oil right? Could this cause more plugs to foul at idle?? How does the jet change affect power and performance?

Thanks for the info, by the way we should go for a spin this winter on the trails...

Brian

 

Eplor, Like Snow ride says Dont go down. The stock jet for the 2000 scrambler is a 230. The manual says to go to a 250 for temps from 0 to 40 F. Im pretty sure there are many sizes in between these 2. and polaris would rather you run rich and keep running then run lean and start complaining. Since the manuals jetting suggestions seem to add up in my case I will stick with there suggestions to start off.

I would make a medium speed run for a bit and check the plug before you go out and rejet, maybe for nothing. basicaly lean is a light to white plug, if its white dont ride it! and rich is dark to black. lean is not enough fuel (burns very hot) rich is to much fuel.

I think you may have to rejet in the winter due to the difference of air density and moisture in the air verses summer. Im sure there are others out here that know for sure. gj

 

All we need is a little more snow so that the clubs can build the snow bridges. We will definatly go for a ride this winter. If its hardpack bring the scram and if its major fluff, take the Xplorer (you will need the ground clerance if you want to follow me)

I wouldn't worry to much about the Xplorer if it's stock. The only time it is critical to have a larger jet is -25c and below. Yes I re-jet every year but only from a 210 to a 220. If you go to the dealer they will most likely say a 230, but your Xplorer will feel and be very sluggish.

The problem is that, you may leave for a ride in the morning when the temps are around -5c and then come home at 3am and its -35c and believe me, you don,t want to re-jet on the trail when its -20c (I have done it). The stock 210 is good to around -20 but any colder than that you will feel the power increase (big time) as the temps drop more, this is where it starts to get risky. When riding at around 0c to -5c you will not be as peppy as with a 210 but its not a very big difference.

Fouling plugs never happens, mostly because you are usually driving 35mph or wot

 

Ok guys, with all this talk about jetting I have to ask even though it's a little off the subject of temperature. I'm about to order an HPD pipe and clutch for my TB. Is rejetting really necessary? If so, how difficult is it to do?

Thanks!

 

00tb250, when you order the pipe ask hpd what they recomend, let them know where you live so they know what elevation you ride in. I think ohio is around 800 - 900 ft. They may include new jets with the pipe. Might also want to get a better air filter too to go with the pipe. a K&N or UNI or Twin Air would also help in the pep department. Most likely you will need to rejet. Ask HPD what what filter they recomend, they will know they did all the testing, alot of people here like them.

As far as being hard to rejet, if you can install the pipe and clutch kit your self you will be able to install the new jets also gj

 

Is it easy to rejet? I would not mind doing it myself but don't want to mess anything up. If any of you have the procedure...let me have it!

Thanks

 

First I want to say that I fully understand the reason why you are supposed to jet "up" with the colder air. Colder air is denser and denser air will cause your mixture to go leaner.

OK with that being said, let me tell you a little story. I have a '99 Scram 400 with the RCR Stage 1 Kit with the midrange pipe. Rick sent me both 270 and 265 main jets. My bike came stock from the dealer with a 195 main installed (I live at 4500 ft. and ride from 5000 to 10K feet) so they jet down from factory. When I installed my pipe I first tried the 270 MJ and it ran ok but seemed a little rich. The 265 was much better and the bike seemed to run like a bat out of hell wide open with only a slight "gurgle" on the extreme low end. My plug readings always were nice and dark and I have never yet fouled out a plug. Now this winter since it has been getting colder here, my performance has gone down the tubes almost completely on the low end and only gets worse as I go up in altitude. It seemed like it was running too rich, but that is counter-intuitive since it is getting colder. I checked my plug and it looked fairly dark like normal. As a little experiment I put the slightly larger 270 jet in and the problem got a little worse.
At this point since this is the opposite of what I expected I decided to give up and just take my bike into my trusted dealer. After 1/2 hour of labor ($30) they tell me it's done. I warmed the bike up and nearly rode a wheelie to my truck (impossible the day before). I took my bike to the same mountain I usually ride and found my power to be MUCH better than before but not quite as good wide open as it was during the warmer months. I looked at the work order and they show that they dropped me down to a 210 main!?! and adjusted the air mixture screw to 1 1/2 turns (not sure where it was before).
My question to you is WTF? A 265 MJ down to a 210 is a drastic drop (certainly one I would have been afraid to do). My bike ran very well last summer at the same altitudes with the 265. What is going on? They say they didn't touch my pilot jet or anything else besided the air screw and main. What do you guys think?