Author Topic: Jet kits?  (Read 1235 times)

jaws

  • Newbie
  • *
  • Posts: 34
    • View Profile
Jet kits?
« on: September 16, 2012, 03:23:55 AM »
Hey guys, trying to tune in my 80cc bbk. I need to find a jet kit that has 100-112. Anyone know of a online shop ( not in asia ) that sells them? I've checked ebay, but the kits don't have the sizes I need. Thanks in advance!j

whiteknight

  • Hero Member
  • *****
  • Posts: 783
  • ..Knight Tweed..
    • View Profile
Re: Jet kits?
« Reply #1 on: September 16, 2012, 04:03:37 AM »
personaly i dont think you will be needing that bigger jets.. i run a 72cc kit with a polini free flow filter with a 19mm race carb and i have a #92 main jet... i tried a 94 and a 96 jet but they were sucking fuel out quicker than the carb could refill so i had to downsize.
do you have any jets? or do you still need to get some. its will be best to get a jet set which has a #80 thru to #100 then you can tune from there, just remember plug chops to make sure your neither rich or lean. you can get a stage 6 jet kit from Scooter Attack but i dont know what size thread your carb accepts. my Motoforce carb accepts a 5mm thread, the standard carbs have a 4.5mm thread so thats summit else you have to check before you order.

hope this helps
Courage is measured in how much tyre you use.

2010 Kymco Agility 72..Naraku 72cc race cylinder...Naraku 50cc race head
Naraku Race CDi...Polini free flow filter...Motoforce Racing Carb
NGK Irirdium plug...Naraku Race Variator...Malossi fly clutch
Stage 6 cnc clutch bell...1500 Rpm torque sprin

jaws

  • Newbie
  • *
  • Posts: 34
    • View Profile
Re: Jet kits?
« Reply #2 on: September 16, 2012, 04:19:08 AM »
I started with an 85 jet, but doing plug checks, the tip was white. I have been slightly reaming the jet using some very small drill bits, but its not exact. The jets in my cvk carb have a tiny thread size, like almost 3mm. Im looking for a tuning jet kit to make my life a little easier. I was I had the bigger thread jet, I work right next to a honda motorcycle shop and they have all the jets in the bigger thread size.

streido

  • Hero Member
  • *****
  • Posts: 3072
  • I view speed limits as guidelines rather than laws
    • View Profile
Re: Jet kits?
« Reply #3 on: September 16, 2012, 12:05:06 PM »
Quote
standard carbs have a 4.5mm thread 

Actually stock carbs are 5mm threads. Keihlin 5mm/M5 jets.

Quote
but doing plug checks, the tip was white.

Tip tells you nothing about the jet size, that only tells you how hot the detonation is. You need to look down deep into the base of the white insulator, or chop the threads off the plug to see properly. You want a nice clean brown/tan/chocolate colour ring at the base of the white insulator.

Look up some plug chop charts and you will see how it should look. Ignore the tip tho for jetting, means nothing.
Chaos is my co-pilot.

blue

  • Hero Member
  • *****
  • Posts: 3935
    • View Profile
Re: Jet kits?
« Reply #4 on: September 16, 2012, 07:20:59 PM »
drill your own get the drill pits they can always be used over and over again.

jaws

  • Newbie
  • *
  • Posts: 34
    • View Profile
Re: Jet kits?
« Reply #5 on: September 22, 2012, 10:48:55 PM »
Ugh, this tuning thing is ever ongoing. I got a metric drill bit kit that ranges from. 3mm to 1.6mm. I started out with a .85 and the plug looked lean, same with the .90mm. So I stepped it up to a 1.0 or 100 jet, and it now pops like it way rich, but the plug doesnt look overly rich. My problem is my buddy, he's raced 4 wheelers since a kid, and keeps saying he knows what the plug should look like when its running correct. He said the electrode ground strap should not have any white on the tip, he says that's lean. I thought I should be looking at the white insulator around the electrode, and tune the carb till it has a chocolate brown color. I just want to make sure im doing this correct, should I tell him his way is wrong? Sorry for the long post, I think I should just put a .95 jet in it and check the plug after a few minutes of riding.

skippy

  • Sr. Member
  • ****
  • Posts: 421
    • View Profile
Re: Jet kits?
« Reply #6 on: September 23, 2012, 11:15:39 AM »
Ugh, this tuning thing is ever ongoing. I got a metric drill bit kit that ranges from. 3mm to 1.6mm. I started out with a .85 and the plug looked lean, same with the .90mm. So I stepped it up to a 1.0 or 100 jet, and it now pops like it way rich, but the plug doesnt look overly rich. My problem is my buddy, he's raced 4 wheelers since a kid, and keeps saying he knows what the plug should look like when its running correct. He said the electrode ground strap should not have any white on the tip, he says that's lean. I thought I should be looking at the white insulator around the electrode, and tune the carb till it has a chocolate brown color. I just want to make sure im doing this correct, should I tell him his way is wrong? Sorry for the long post, I think I should just put a .95 jet in it and check the plug after a few minutes of riding.

your right to reading the jetting. he is reading how hot the engine is running...
check this out........http://www.braigasen.com/howtoread.htm
                                                and this.
                            http://www.4secondsflat.com/plug_chart.html


that should help you a little. depending on the set up of your engine from other people withn bbks they are running from 90-105 or so
 so i think that is the best range it will take ages to get right what works one day will be bad other days. just find a happy medum.

i may self havent the bbk but just after market filter and leo vince and im still in the middle of chops my self but at the mo i have got it down to 90 - 93 jet  i know it needs to be in that range.

use a new plug each time....... not an old one cleaned up. and make sure you do cut each plug up. its not cheep but the only way to get it correct..


good luck.
                           

An Error Has Occurred!

Call to undefined function split()