Yet Another XT350 Jetting thread....

Hello! I have a 1986 XT350. I believe the jetting may be stock. I have bored the engine out 1.5mm over and I have installed a Uni foam filter. Except what I had mentioned, the bike is stock; no drilled air box nor grounded header welds. I would like to inlarge my jets in hope for a nice, healthy running engine, however I am not sure what size I should go up to, nor where to get them. Also, I would like to up the pilot jet to help to get it started- unless this would create more off throttle bog; but I can not find out where to purchase the poilet jets either.

Summary of my questions:

1) What recommended jetting should I try?

2) Where should I purchase them?

3) Should I jet it a little rich- better too rich than too lean, correct?

4) Do I have to rejet BOTH carbs?

5) Would an uped pilot jet create greater bogging off the throttle?

6) Is there any other information you would like to add that you feel that would help me?

Other helpful information:

I live in North-Eastern Ohio

Elevation is 1160 feet above sea level

Roughly adverage 70% humidity

I would not like to purchase a jet kit

but I would like to purchase individual jets.

Thank You!!!

Colton W.

Start with a 130 main for the primary carb. Buy it from the Yami dealer. It's from an XT600.Shim the needle on the primary carb. I cut off the eye of a small elecrtical connecter and so have a few others.

Turn your pilot screw out to about 3 1/2 turns from its seated position. (might have to mess with this a little)

Leave the secondary alone.

There are other ways to get the same results, but this is a good place to start.

I've seen posts about pilot jet sources, but I haven't tried any. Drilling it out is too big of a step so don't bother. I used a small torch tip file to open mine up a little. I have no how much it opened it up or if it did anything at all. I didn't really need to do it, I was just trying stuff out. Might be a waste of time.

Of course, I have to add my standard advice.

Make absolutely sure you'r intake boots are in good shape. If the rubber is pealing back AT ALL, replace them. They will start to leak soon.

Edited by jsnmid

x2 on what jsmid said. do not expect the plug to change colours right away, takes a bit for it to work.

Start with a 130 main for the primary carb. Buy it from the Yami dealer. It's from an XT600.Shim the needle on the primary carb. I cut off the eye of a small elecrtical connecter and so have a few others.

Turn your pilot screw out to about 3 1/2 turns from its seated position. (might have to mess with this a little)

Leave the secondary alone.

There are other ways to get the same results, but this is a good place to start.

I've seen posts about pilot jet sources, but I haven't tried any. Drilling it out is too big of a step so don't bother. I used a small torch tip file to open mine up a little. I have no how much it opened it up or if it did anything at all. I didn't really need to do it, I was just trying stuff out. Might be a waste of time.

Of course, I have to add my standard advice.

Make absolutely sure you'r intake boots are in good shape. If the rubber is pealing back AT ALL, replace them. They will start to leak soon.

Ok so i'm clear. Your bike is stock, your just making up for the lean factor from the factory?

And as far as shimming the needle, your talkin bout pullin the slide needle out, puttin the spacer between the slide and the seat where needle sits in slide correct? any particular size thickness i'm shootin for here? (use of a micrometer is no problem on my part..)

And as far as using a torch tip cleaner, What size ya use? (if ya can remember)

NOW, as far as your advice on intake boots, Mine look great. i been over em with fine toothe metal comb. (ive read about the boots EVERYWHERE! lol not to mention i have an extra set from my parts bike)

Thanks Jsnmid.

Ok so i'm clear. Your bike is stock, your just making up for the lean factor from the factory?

And as far as shimming the needle, your talkin bout pullin the slide needle out, puttin the spacer between the slide and the seat where needle sits in slide correct? any particular size thickness i'm shootin for here? (use of a micrometer is no problem on my part..)

And as far as using a torch tip cleaner, What size ya use? (if ya can remember)

NOW, as far as your advice on intake boots, Mine look great. i been over em with fine toothe metal comb. (ive read about the boots EVERYWHERE! lol not to mention i have an extra set from my parts bike)

Thanks Jsnmid.

Yes, it is more or less stock. I have a uni filter and my stock exhaust has been slightly modified. I smoothed out the welds on header pipe flanges on the engine side, and I made some small modifications to my muffler to help it flow a little better. Nothing drastic, and not anywhere near what an aftermarket muffler would give you.

RE, shimming the needle. You are correct.

Iot sure what size the "washer" is. I actually couldn't find a regular washer thin enough in my bolt bucket. That is why I used the electrical connector eye. I had the right size hole and it was thin enough I could stack them if needed. I may have ended up using 2. I don't remember.

The torch tip file was the one I could fit through the jet but had some resistance. There was only one that worked. Next size down did nothing and next size up wouldn't go in at all.

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