hi guys I spent the afternoon working on my zip yesterday, but after fitting the following parts my jetting is really strange because it will only run well with a jet that seems too small! Right standard a/c 50, I've fitted a ZX pipe for now and 6g rollers, then a 60 main jet (phva 17.5mm). Test rode and it ran mint. Then removed the airbox to run a open filter (no air filter at all just a piece of J cloth I cut out to fit over the intake, so it still gets clean air). And fitted a 66 jet to suit, went for a test ride and it ran shit! very very boggy all over couldnt get 30mph even. Went back, checked plug and it was a dark gray colour and dry. Decided to upjet slightly more to a size 72, tested again and it ran even worse and actually barely started!! So down jetted to a 70 (shit) then 68 (shit) engine still hardly even running, so I sat there confused for a little bit then decided to check the plug again, it was wet and black so way too rich.. Down jetted again to a 60 jet (what I bloody started with). And it runs well! Not perfect but close, plug is now coffee brown and I feel it will run better with a 58 jet. What I dont understand is why I have to use such a small main jet without the airfilter for it to run, I ended up fitting a 60 jet which is what I had to start with (after fitting pipe, before it had a 53). Ive checked the manifold for splits and its fine
Fuck knows but it keeps the big shit out lmao, was just riding a min ago and it smokes a little even when warm, plug tests still coming out nice but I havent needed to upjet, upjetting it only makes it run worse :rofl:
mate, get an air filter, seriously, wat is it these days? i peple riding around with a sock for a air filter,household sponges cable tied on carbs, even seen wire mesh on carbs (supposedly look cool) . any cheapo FILTER is better than a cloth wich will not allow sufficient air flow
Just so you know my speedfight likes small jet sizes too, its a 50 a/c with a giannelli reverse pipe, malossi variator kit and red malossi foam filter and it runs best on 58 jet. When a friends speedfight 1 with the same bits but l/c runs on 70-odd jet. Both bikes do about the same speed.
got the air box back on now and it runs LEANER! tick-over is high and plug colour is lighter. running a 60 main jet with zx pipe so it could be ok.. ive tried to set the idle mix but ive forgot what the setting is isnt it 1 and half turns out??
