Just re-jetted

[b-b00gie]

Here's the situation... I have a 99 KX125 all stock, just got a Pro Circuit exhaust and pipe. I called them and they recommended re-jetting.

Here's what they recommend:

158 Main (same as stock)
50 Pilot (45 was stock)
2 turns out on air screw (1.5 was stock)
2nd clip on needle (3rd clip was stock)

I installed everything today and re-jetted. I havent gotten to ride the bike yet but I fired it up to check the response.

At idle there is almost zero smoke coming out. Same thing when I start to give it little throttle.

When I give it a healthy dose of throttle, I get white smoke coming out of the exhaust. It doesnt seem to bog or anything but there's more smoke than I used to have.


I understand that from going from a 45 to a 50 Pilot, I am now richer on the pilot. The airscrew is leaner however, as is the needle clip position. (2nd clip was 3rd, I think that is leaner).


Whats with the smoke at mid to full throttle?

 

[Jaybird]

I'm curious...what did your call to PC consist of? Why did you call them?

 

[b-b00gie]

Someone told me that their PC pipe came with a recommendation to change their jetting, and the settings to change. I ordered my pipe from an online store and it came w/ nothing but the pipe. So I took someone's advice and called PC.

The call consisted of...

Receptionist: "wah wah wah, how can I help you"
Me: "can I have the tech dept?"
Receptionist: "do you haven an engine related question?"
Me: "yes"
Receptionist: "let me give you (forget name)"
Me: "thanks"

Whoever: "this is whoever"
Me: "hey, I just bought your pipe and shorty exhaust for my bike. do you recommend changing my jetting with this setup"
Whoever: "oh yeah. what kind of bike"
Me: "99 kx125"
Whoever: "ok, just give me a sec..."
Me: "no problem"
*hold for a few*
Whoever: "sorry about that, 99 right?"
Me: "yep"
Whoever: "ok, stock main, 50 pilot, 2nd clip on stock needle, air screw at two turns out but you can vary that to your liking"
Me: "how about the plug? same one as stock?"
Whoever: "we dont have a note to change it, so I'm assuming yes. mix at 32:1"
Me: "Ok, I'll start from there, thanks."
Whoever: "Not a problem at all, take it easy"

 

[Jaybird]

Wow, I didn't realise PC had such a technically apt staff!

b, there are many other factors to consider when it comes to jetting. The call to PC is what I suspect lots of folks do for jetting information, and it's probably alot cheaper than buying a MXAction issue...depending on how long they had you on hold. Both MXA and the wiz's at PC will give you about the same level of information concerning jetting specs.
Or maybe should I say "out of level".

I would suggest you go to Eric Gorr's site, or do a search here to find out the real scoop on jetting. It's just not as simple as PC makes it out to be.

 

[Moto Squid]

You can't test jetting by making lots of noise while it's on the stand...you have to go and ride it. I've tried the stand jetting cheater method, it doesn't work. When you ride it don't be afraid to change the main or needle or air screw and if the power gets worse go the other way. That's how I learned the basics in jetting.

 

[Rockey5000]

What there saying is get a jetting guide (how-to) and do it yourself, to get the best results.

 

[cr25096er]

just ride the bike. jet it after you see how it is.

 

[b-b00gie]

Question... after swapping jets and putting the carb back together, should I have used thread lock on the 4 screws? If so, which strength???

 

[Peer Lovell]

I'm assuming you mean the screws that hold the float bowl to the carb?
If so, no you don't use lock tite on these. There should be split ( lock ) washers with these screws.

 

[Jaybird]

You should throw them away.
Buy some socket head cap screws and replace the screws that hold the bowl on with them. You will be glad you did.