Winter Jetting for YT175

[200XMichigan]

I picked up this YT175 this summer and I have rebuilt the carb and put in Boyesen Power Reeds, I moved the needle up one notch to richen it up for winter, should I get a larger main jet? Any tips on jetting it right for winter would be great. It has a stock air box and Uni foam filter. Other than the power reeds everything is stock.

[Yamaha_Rules69]

You may have to go up one to two sizes, depending on how cold it will be. Do a plug chop from time to time to determine if the engine is running lean. Good luck!

[200XMichigan]

It got down to 18 last night. Is it better to go two jet sizes up so it can start in the bitter cold. Does moving the needle up more than one clip position do much or should I just order some jets? I thought 2 strokes were so simple but getting this one jetted right is really difficult. It runs great but wants to be primed to start when its cold which is really frustrating. Does anyone go to one step hotter of a spark plug in the winter?

I have been doing some reading and am I correct that thet pilot jet should also be changed to one larger for winter since it is the most important for low idle mixture?

If one of your YT175 is stock and you know off hand what numbers your running for jets that would be great since our winter temps are real similar. The thing is so clean and nice but start terribly when cold.

[Yamaha_Rules69]

You could try adjusting the air/fuel scews to make the pilot circuit run a little richer at low idle. As far as raising/lowering the needle, you would be better off to get it jetted correctly with main jet before you mess with the needle. Most times it will run fine where the needle is supposed to be - in the 3rd position, if the main jet is correct. When was the last time the carb was thoroughly cleaned? The pilot jet may have a partial clog, and that would make it that much harder to start. I had a lot of problems with my 175 pilot jet getting cloged. I drained the tank, flushed it and everything, but it would still get clogged even with a fuel filter on. I was using a screen type fuel filter, then decided to switch to a small paper element filter, and never had a problem again. This may or may not help you, but just thought I would throw it out there. Good luck!

[200XMichigan]

Thanks. I cleaned the carb this spring when I bought it so everything is real clean, there's an inline filter I added. It started on the first pull this morning, once things had warmed up slightly above freezing. Going to go up one size on the pilot jet for the real cold temps. Those power reeds are great, first ride with them in and it made it up all kinds of crazy stuff.