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leak jet and ap timing

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bike was running great last year. yesterday i developed the dreaded bog. took the carb off and cleaned it, then started to check the timing of my squirt. the squirt was coming up short. so i put in a #40lj and it measures .4666666 sec. is this too short? it just misses the slide and shoots about 3 1/2 ft. it was around 70deg yesterday, which my jetting is set for these temps. i am also using the heavy o-ring on the linkage. should i go down to a #35 or block off the leak jet?

anything i may be missing? thanks.

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Your squirt duration sounds a little short. Go down one size on the leak jet.

BUT FIRST!! Make sure you're testing the bike with it fully warmed up. Also don't bother to test it on the stand. Make sure you've ridden it around for 10-15 minutes and then test it while riding.

Also, the AP and leak jet aren't all there is to the bog. The rest of your jetting, especially the pilot circuit and needle position have to be right too. Have you properly adjusted your fuel screw so that it idles crisply? If not, see the sticky at the top of the jetting forum.

How is the mid-throttle response? If you feel it could be better, move your clip position up one then down one, and pick the position where it's the snappiest at mid-throttle.

Once these things are set properly, if it still bogs, then you might try a different leak jet. 0.466 sec is awfully close to .5 sec, and your bike might run just fine there, provided the rest of your jetting is set correctly.

barton

ps: Also being spring, your carb is all cleaned out, and you've got a fresh air filter on it, right?

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ok, today is 20deg cooler than yesterday and rainy. i rode around a little this morning to warm up the bike. i noticed a slight popping from 0-1/4 throttle when holding throttle at a constant position. adjusted the fuel screw to no affect. so i may be a little lean on the pilot circuit. i will wait to do further testing when i have a dya like yesterday(70deg and sunny) to compare to. i cleaned out the carb and installed a fresh air filter yesterday when i first noticed the bog. i double and triple checked the pilot jet to make sure it was clear. it did not help much. my linkage gap is .140. i readjusted the screw to where the free play stops, and remeasured. it is still .140. the bike pulls great from mid-wot. with the weather today i may pull the carb and clean it again just to be sure.

180 main

40lj

42 pilot

needle stock 4th pos.

fuel screw 2 1/2 turns out

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ok, today is 20deg cooler than yesterday and rainy. i rode around a little this morning to warm up the bike. i noticed a slight popping from 0-1/4 throttle when holding throttle at a constant position. adjusted the fuel screw to no affect. so i may be a little lean on the pilot circuit.

42 pilot

I agree. It's cooler, go up one on your pilot and report back. Sounds like a lean bog in this case. Please try asap and let us know.

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i have to wait until tomorrow to pick up a 45 pilot. the largest i have is 42. tomorrow it is supposed to be 74 deg though.:bonk: so we shall see how it runs tomorrow and go from there.

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If the bog started just after you put a fresh filter in it, you may have sucked a little filter oil into the pilot AIR jet. Make sure you clean out both of those passages at the bottom of the carb's intake bell.

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so, today is 75deg and sunny. the popping while on constant throttle had gone away. i installed the #35 lj and went for a ride. the bog was all but gone. if i used the clutch or down shifted before accelerating, i had no bog. it did it very slightly when i was at idle or in very low rpms, but would pull after 1/2 sec or so. i then put the #45 pilot jet in, adjusted the fuel screw and went for a ride. bike ran great, no bog at all:applause: . not even when sitting in neutral. thank you all for the help.:bonk:

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sweeeeeet, no problem, way cool of you to act quickly and post your results.

I just don't appreciate good jetting until I've had it for a while, then I ride something that isn't properly jetted. Makes you love a nicely jetted bike, such a big difference in behavior.

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