Carb jetting help

BD1415 · 09-25-2022, 04:21 PM

I have read countless threads and watched videos about jetting carbs. I can’t seem to jet my new nibbi pe30 on my hawk 250. I changed the pilot jet to a 38 and main jet to 120. When it idles it’s a very high idle. I try to adjust the idle and mixture screw with no success. Anyone out there who can help me get my hawk tuned in?

Wild Dog · 09-25-2022, 07:47 PM

I know it may sound silly, but let's go by the most basic

Did you adjust the idle speed knob?

If Yes.

Is there enough free play on the throttle cable, it may be holding slide up, making the motorcycle idle to high.

Also check that the slide is not getting stuck.

ScoTT250 · 09-26-2022, 02:11 AM

+1 on what Wild Dog said. Definitely check that slide if you haven’t already. I’ve had them seem like they’re in properly but then rotate at the last second. You can still get the cap on but they aren’t all the way down.

By “no success” do you mean you can’t get the idle down or can’t get it to change at all?

Ol,fart · 09-26-2022, 02:22 AM

Quote:

Originally Posted by Wild Dog

I know it may sound silly, but let's go by the most basic

Did you adjust the idle speed knob?

If Yes.

Is there enough free play on the throttle cable, it may be holding slide up, making the motorcycle idle to high.

Also check that the slide is not getting stuck.

I would like to add, once you get the idle down then set the idle set the idle air adjustment to the highest rpm(and highest vacuum) then adjust the idle screw again.

BD1415 · 09-26-2022, 04:08 PM

Thank you for the replies. It must have been the throttle cable. I decided to take apart the slide and put it all back together and when I did the idle was much better. I was able to adjust the idle and mixture screw afterwards.

alex_in_az · 09-26-2022, 08:24 PM

Quote:

Originally Posted by BD1415

Thank you for the replies. It must have been the throttle cable. I decided to take apart the slide and put it all back together and when I did the idle was much better. I was able to adjust the idle and mixture screw afterwards.

what are you using for an intake manifold?

09-25-2022, 04:21 PM	#1
BD1415 Join Date: Sep 2022 Posts: 2	Carb jetting help I have read countless threads and watched videos about jetting carbs. I can’t seem to jet my new nibbi pe30 on my hawk 250. I changed the pilot jet to a 38 and main jet to 120. When it idles it’s a very high idle. I try to adjust the idle and mixture screw with no success. Anyone out there who can help me get my hawk tuned in?
	0

09-26-2022, 02:11 AM	#3
ScoTT250 Join Date: Jan 2022 Location: CA Posts: 16	+1 on what Wild Dog said. Definitely check that slide if you haven’t already. I’ve had them seem like they’re in properly but then rotate at the last second. You can still get the cap on but they aren’t all the way down. By “no success” do you mean you can’t get the idle down or can’t get it to change at all? __________________ Scott CA High Desert Currently: 2021 TT250 1981 XL 185 project 2003 Buell Blast P3 (for sale) Formerly: 1986 Suzuki GS450 1979 Suzuki GS400 1968 Honda CT90 1974 Suzuki TS250 1978 Honda XL175 1997 Suzuki GS500E
	1

09-25-2022, 07:47 PM	#2
Wild Dog Join Date: Dec 2016 Location: Argentina Posts: 756	I know it may sound silly, but let's go by the most basic Did you adjust the idle speed knob? If Yes. Is there enough free play on the throttle cable, it may be holding slide up, making the motorcycle idle to high. Also check that the slide is not getting stuck.
	1

09-26-2022, 04:08 PM	#5
BD1415 Join Date: Sep 2022 Posts: 2	Thank you for the replies. It must have been the throttle cable. I decided to take apart the slide and put it all back together and when I did the idle was much better. I was able to adjust the idle and mixture screw afterwards.
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