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-   -   Pilot Jet Increase (http://www.gz250bike.com/forum/showthread.php?t=5398)

Kcarvajal 05-06-2012 10:57 PM

Pilot Jet Increase
 
Hi guys. I haven't been here in a while. Been busy tinkering with my bike which I've changed countless times already.

Here's my bike, along with my friends' during a ride this weekend. Fun ride.
[attachment=0:1pi176jp]photo.JPG[/attachment:1pi176jp]
Anyway, any of you ever have to increase the pilot jet? I installed a larger air cleaner and can't seem to dial it right and think I need to go bigger.

Thanks, and safe riding this season!

Ken

PimpS 05-07-2012 02:53 AM

Re: Pilot Jet Increase
 
Beautiful! Good job indeed!

jonathan180iq 05-07-2012 08:44 AM

Re: Pilot Jet Increase
 
To my knowledge, no one has ever gone above a 135 and that was pretty extreme. I think with just an air filter I was sitting 122.5 or 125. Most people, even with both intake and exhaust done, settle somewhere between 125-130. I would try a 130 with what you have and then dial back the other adjustments.

EDIT: So I see you are referring to the Pilot
We haven't seen a lot of pilot changes. Mostly just some adjustments here and there. What do you currently have it turned to? I mean, either way, as you know, you can just swing in to the local Japanese bike shop with your factory jet and see if they have some larger matching ones. The pilot is always the biggest pain in the ass to get set right the second time though. Good luck, man.

raul10141964 05-07-2012 01:37 PM

Re: Pilot Jet Increase
 
I running with different air cleaner an set my pilot at 2.5 turns an change the main jet to 140 , ask for small mikuny main jet

Kcarvajal 05-07-2012 03:18 PM

Re: Pilot Jet Increase
 
Thanks gentlemen!

Jonathan, I think I have it 3 turns out.

I bumped my main to 140 from 130. It actually runs really well and feel that I can easily keep up with my buddies. (OK, separate topic).

I'll check things out this evening. Screw in is lean, out is rich, right? Just want to confirm I'm doing this right.

Ken

blaine 05-07-2012 04:42 PM

Re: Pilot Jet Increase
 
Quote:

Originally Posted by Kcarvajal

I'll check things out this evening. Screw in is lean, out is rich, right? Just want to confirm I'm doing this right.

Ken

You are correct.If idle mixture screw is on back side of carb,the opposite is true!!
:) :cool:

jonathan180iq 05-07-2012 04:50 PM

Re: Pilot Jet Increase
 
Are you guys with 140s running straight open headers, no baffles or anything?

Kcarvajal 05-07-2012 05:08 PM

Re: Pilot Jet Increase
 
Hi! Yes, no baffles, straight pipes. Bad? Pls say no.

Rookie Rider 05-07-2012 10:49 PM

Re: Pilot Jet Increase
 
sounds good to me.... i think...... how does it sound anyway ?

Water Warrior 2 05-08-2012 01:00 AM

Re: Pilot Jet Increase
 
Quote:

Originally Posted by Rookie Rider
sounds good to me.... i think...... how does it sound anyway ?

Bum bum bum rat ta ta ta ta ............or there abouts.

jonathan180iq 05-08-2012 08:11 AM

Re: Pilot Jet Increase
 
Quote:

Originally Posted by Kcarvajal
Hi! Yes, no baffles, straight pipes. Bad? Pls say no.

Well, if you have it jetted properly, it's fine. I was just cracking open the giant book of GZ knowledge and only a couple of people have ever needed anything more than a 135. Everyone who seems to stop at the 135 threshold did have some type of baffle or resonator though. So that makes sense.

Next time, when people come in asking for what jetting setting to start at to try and figure it out, we'll have a little more to go with.

jonathan180iq 05-08-2012 08:12 AM

Re: Pilot Jet Increase
 
[quote=Water Warrior]
Quote:

Originally Posted by "Rookie Rider":3sza8uq4
sounds good to me.... i think...... how does it sound anyway ?

Bum bum bum rat ta ta ta ta ............or there abouts.[/quote:3sza8uq4]

I think it'll be more like:

"fwop fwop fwop fwop fwaaaaaaap BLAAAAAAAAAAAAHHHHHHHHH.

Kcarvajal 05-08-2012 09:47 AM

Re: Pilot Jet Increase
 
Well, to me... I can't hear any difference when running 130 and 140 main jet. It is loud though. I'd say sounds more like what you described, Jonathan. I'll try to record it. Gotta figure out how to do it without distortion.

One thing though, it seems zippier since the 140 jet. It could very well be my imagination but was keeping up with my buddies who are on bigger bikes with no issues. Was on the highway and it was much more comfortable cruising. Like I said, I could be going nutty. But I have an 18" rear wheel, 38T Rear sprocket, 16T front.

Ken

jonathan180iq 05-08-2012 03:35 PM

Re: Pilot Jet Increase
 
You're not nutty. It was probably just that you needed a larger main and just didn't really know it, since the 130+ was making it run "alright".

When jetting on your own, to get it really dialed in, the only way to do it by trial and error and then settling for what works "best".

I'm glad you got it sorted. A larger main and a slighty richer mixture will also help the bike run a little cooler and we all know how important that is.

Kcarvajal 05-08-2012 07:57 PM

Re: Pilot Jet Increase
 
That's comforting. I'm glad I'm actually doing something good vs harming my bike.

Thanks guys!
Ken

Rookie Rider 05-08-2012 09:22 PM

Re: Pilot Jet Increase
 
i cut my muffler off today, goto PERFORMANCE MODS section and check out the pics.

Rookie Rider 05-16-2012 12:54 PM

Re: Pilot Jet Increase
 
Jonathan 180iq has been a huge help to me with the jetting.


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