Mikuni 26mm spitting fuel when kicking. & Tuning?

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RangaBlitzFanga

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This is the stock carb on a Dpro 160. Noticed from day dot it spat fuel when using the kick starter, doesn't spit fuel when the bike is idling

Thought it could be the float plunger sticking, pulled it apart and it operates smoothly. Checked the float height, not sure if i'm measuring it at the correct point, but from the flat metal of the carb, to the metal of the prong (just behind the float, closest to the plunger) it measures 15mm which if anything should be borderline lean not rich?

I'm also wondering about jetting. I noticed the needle is on the richest setting, didn't make a note of what main/pilot jets are in it though.
Whats a good jetting for these bikes? I thought it was a bit rich to start with as it puffed a little black smoke (restrictor in) and wacking the throttle quickly. Tried raising the clip position 1 and just going by ear it seems to pull a little less punchy and likes to rev quicker/smoother with choke half on. Should I be going with a richer needle?

What about pilot/main/air screw? those i've left stock
Bike as it is takes a good 5-6 kicks to get going, and needs some throttle otherwise it just won't start. Does idle ok but won't start otherwise
 
sounds like it needs a bigger Pilot Jet, standard the china Mikuni 22/26 usually have a #15,
i'd swap it for a #20, or possibly a #22.5 ?

and with it spitting fuel, adjust your valves, they will be set too tight.
.003" on the inlet, and .004" on the exhaust
 
and with it spitting fuel, adjust your valves, they will be set too tight.
.003" on the inlet, and .004" on the exhaust

Would like someone to confirm this, i've never heard of a bike spit fuel because valves were out?

That said I have another question with valves, have set them both to 0.003/0.004 respectively but I believe I can hear a little tapping, could be i'm being super paranoid but i'm not sure if my feeler gauges are accurate enough. I can slide a 0.003 in with some drag, but also a 0.004 and even a 0.005 if I REALLY try (doesn't move smoothly). Blast these stupid angles valve covers!
 
have set them both to 0.003/0.004 respectively but I believe I can hear a little tapping, could be i'm being super paranoid but i'm not sure if my feeler gauges are accurate enough.
can you still hear the tapping when the engine is warm, after riding for 10mins or more ?
most pitbike engines do it, Lifans included
and at least you know you are not going to burn out your valves, and have other carby problems

it will only spit when kicking it over, because once it's running, the fuel is being sucked into the engine.
 
aggressive cams this is quite normal, also bad sealing inlet valve could also be a issue

its probably nothing though this happens with all bikes usually only now and again
 
mine will consistently spit fuel when kicking, doesn't really bother me all that much but it's not exactly normal bike design to have them do it
Plus this bike doesn't even have 2 hours on it yet

So jets, whats the best suited for the Z160HO's? it's still a stock dpro with a unifilter. Won't be changing the carb as i'm happy with its performance
 

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