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Still not happy with my jetting

Well after the 45 pilot was put in there is a ton more snap off the line at low RPM and low throttle. Didn't get a chance to take it out on the hwy yet and see how it does at higher RPM's and where it kicks into the main circuit. Gonna take it on a 60 mile trip down the hwy/interstate later today... We'll see how it does in the hills during roll off/roll on. I think i can get a better feel for the main jetting there.

If it still stumbles after the roll off/roll on i think i'll break into the top side of the carb and mabye shim the needle, or drop it one... We'll call this the DJ's last chance before i get a new slide and emulsion tube etc.
 
One last thing strikes me. Did you open up and clean out/change the diaphragm in the accelerator pump?

Next time you have the bowl off, take your carb cleaner spray and using the red tube, spray up through all the jet orifices to make sure they are completely clear. I am talking about the orifices that run up in the carb body to the throat, not the jets themselves. Cover up the bike with some old towels while you are doing this so that you don't get that stuff on the paint.

TQ
 
First time we broke into it we took everything rubber out of it, the jets out, disected the accelerator pump, and soaked the carb and parts in chemsol. Then while putting it back together we adjusted the accelerator pump spray to hit the needle instead of spraying all into one cylinder. I hear when it hits the needle it makes a mist into both cylinders. Everything to do with the carb was cleaned thourally.
 
SpringerSteve98 said:
First time we broke into it we took everything rubber out of it, the jets out, disected the accelerator pump, and soaked the carb and parts in chemsol. Then while putting it back together we adjusted the accelerator pump spray to hit the needle instead of spraying all into one cylinder. I hear when it hits the needle it makes a mist into both cylinders. Everything to do with the carb was cleaned thourally.
Click to expand...

Excellent!

Well, I would spend the pesos to take out all the foreign stuff and set the carb back to OEM configuration. Try the 46 low and a 185 main. Glider likes a couple of #4 washers under the needle. See how she does with that set up. If necessary, you may need to drop down a size on the low if it is too rich. Start with 2 1/2 turns out on the idle-air mixture screw. Adjust from there. With the new slide, PLEASE do not drill the air port. You will find that suggestion out there, but it makes the throttle VERY squirrelly (believe me!!).

TQ
 
Well the woman wanted to take the bike down to Branson, which is about a 300mi round trip... After the pilot was changed it ran quite a bit better, no more coughs at all at any rpm reguardless of roll off. I did notice it was still surging on roll off... So while we were there in a motel parking lot i tore into the carb again knowing i could get it a bit better.

Took the needle out of the top end of the carb, moved the clip down one notch. Put it back together and voila. Rode around Branson for about 80miles (half of the time stuck in traffic) and got about 37mpg. But then on the way home between 60-75mph i averaged about 43. No surging, no coughing, no hic-ups. And it was a much more enjoyable ride. Can feel the main jet kick in a little (almost surges forward when it does) when you get on the throttle. That doesn't bother me... It SHOULD surge a little. Plugs look a little rich while in town, theres a lot of carbon build up... When i pulled one after killing it coasting into a rest area it looked real good i thought. This was after about 25 miles of solid 70mph. A little dark.. Mabye a shade darker than peanut butter. I think i'm gonna leave it as is for the rest of the summer... I have the throttle response i'm happy with, starts a ton easier. There is a small puff of black smoke when i first rev it though... I'm thinking thats just the accelerator pump.
 
It surges a little when i roll ON the throttle now... Like when the main picks up. I can't see any surging or stumbling at all when i roll off, or after a decel.
 
Shouldn't ever see surging rolling off. Check for intake leaks then add the washer.

The surging (if that is what it is) would be caused by a improper balance between the fuel circuits in the carb like going from the low circuit to the high circuit. Once you get the right balance of jetting and needle settings (height) , it shouldn't surge.

This is based on having the right parts in the carb and not a mix of different DJ parts and HD parts.
 
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Well i had surging while rolling off... But after moving the clip it doesn't surge while rolling off. I also noticed the engine sounds a ton better. A lot less like a lawnmower with no exhaust. It just runs "crisper" for lack of better words. I'm almost positive there is no intake leaks, but i haven't sprayed any carb cleaner or anything around there to test, but after taking it down the second time i did replace the rubber boot that seals the carb to the intake. It was 8 bucks, why not, eh? I'm not sure if i would call what i have now a "surge" When i roll on the throttle it feels kinda like a boost when i hit a certain RPM, or certain part of the throttle (about 1/4 throttle) and it just feels like it wants to get moving. I think this might be caused by my pilot being a little rich. When i putt around in town my plugs get darker than i'd like. Which brings me to my final question... Which way do i turn my mixture screw to lean it up some? I was thinking clockwise (less turns out) to lean it up. Am i right?

I should add... When i close the mixture screw all the way. (seat it lightly) The engine does not stumble, but this isn't the best idle.
 
Turning it clockwise will lean it out.

You're finally giving me something to go on here. If the engine doesn't quit when you lightly seat the screw, the low jet is too big. Now go change it and come back with the results.
 
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