Forums 🚥 PIT STOP 🔧 Hyosung Technical Help [Tutorial] How to swap Carb Main Jets – Hyosung GV & GT 125/250 Reply To: [Tutorial] How to swap Carb Main Jets – Hyosung GV & GT 125/250

#1577

♠️ MARCEL
Administrator
  • Topics: 32
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Nov 30, 2017
@mf448kxn6
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Hi, im New to motorbike mods and may seem like a noob question but where do you get the jets from because I’m seeing sellers asking to make sure there the right size as there all different, also looking on just eBay for k&n air filters it claims it makes no difference to a stock setup are they worth getting if I have ss pipes, thanks in advance

If you can’t get Mikuni jets for your bike , just email me and I will find out for you.Do you know a local bike garage that keeps a stock of jets as the Mikuni brand is used on other bikes too. I always send out some bolts, ebc jets & filters to some who already have ss pipes.

If you get jets from another source, be wary of cheap china brass as they gum up easily!
Can be a nightmare cleaning them out haha.
hyosung pilot jets gt125r

K&N 650 filters push about 2/3x more air than stock.   In fact, the stock setup already needs bigger jets as the factory versions are too small.

If you have SS pipes  or K&N Filter  (whichever comes first) ,  jets will need to be changed or there is a risk of overheating the rear or piston wall glazing.

Take out your spark plug –  this colour below (coffee brown) means fuel / air / exhaust system is optimal.
Center is “CREAM / BIEGE” in real life.
ngk laser iridium plugs hyosung cr8e ix

If its a pure white colour in the center, then it’s lean, which doesn’t help with the risks i mentioned above ^ ^

If it’s sooty black = that means it’s rich, the fueling system needs cleaning (carbs in this case) or plugs / coils need inspecting or  it’s getting too much fuel with less air   (clogged filter)

// Meditation doesn't mean you have to sit still....

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