Richer main jet killed my "hit"

Since I've heard that the stock jetting is too lean with the baffles removed, I swapped my 168 MJ out for a 172, opened the air screw from 1 1/2 to 2 1/2 (45 PJ), and put on a White Bros. air filter. Now the bottom end is stronger, but the transition to midrange is very smooth. With the prior overly-lean stock MJ, I had a very cool & fun "YZ hit" in the midrange. I'd like to keep the WR timing stock, I like the engine braking on single-tracks, and fuel economy for those long desert rides. Can I get the "hit" back with a needle change? WR timing, 45 PJ (2 1/2 turns out), 172 MJ, no baffles, cut throttle stop, 1-3K feet.

I have the same setup, except airbox lid on.

I use the same jetting, except i moved the needle clip to #4 from #3. For me, this cleaned up the jetting and gave better low-mid. More importantly it cleaned up the hesitation snafu.

However I run at 600 feet, and my fuel screw is not out as far as yours' is. Every bike is different, so experiment.

I would try #4 clip position first before buying anything more. The "hit" your talk about is definately there, but it is smooth.

PS When Clark talkes, people listen

Thanks for your input, I'll give the #3 position a try with my stock needle (DTM?). Clark, do you have any suggestions for the best "hit" with WR timing?

Mcarp, the hesitation you are talking about, is that from idle to giving it a quick twist?

I just tried Mike Trains idea on removing the baffle and using the auto exhaust trick until I save up enough for the Big Gun. Went to 142, 45 and 1-3/4 turns out. And if you remember I live fairly close to you. How many turns out is your air screw.

Anyways, I have that prob with the hesitation (idle-quick twist) do you think I should try moving the clip to the #4 position?

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