DollarStoreMotorcyclist
New Member
Alright so a few months back I bought a pawn shop beach cruiser and bought this 50cc 2 stroke kit off of amazon to put on it and it has been mostly running great with my highest flat land speed record at 26mph (42kmh) after removing the exhaust baffle.
I noticed after leaning the fuel-oil mixture to 40:1 from 16:1, full throttling 4 strokes all the time at mid-high RPM and does it much sooner than at 3/4 throttle so I suspect my main jet is probably too rich given I live at ~5000 feet altitude.
I have my carburetor pulled apart and measured my main jet and tried to find a set online but it seems like my main jet is a unusual spec. Calipers say the threading is M6x0.75 (6mm diameter x 0.75mm pitch) with a 5.5mm head diameter and a total length of 9mm with the head being 4mm long and the threading portion being 5mm long. The hole diameter is ~0.6-0.7mm I think but it's hard to tell even with calipers.
I've already tried playing around with the needle clip (even using tiny shimmies to fine tune it) but I've basically perfected all but wide open throttle. I've also drilled some holes into the stock air box but it's still pretty rich at full send.
Anyone know where to find a jet that fits the specs above? Any help you guys can provide is greatly appreciated. I really want to break 30mph!
Here's a picture of the jet for reference. Most listings I see, the head diameter is 7mm while the threading is typically M5 or M6 but with 0.8mm pitch.
I noticed after leaning the fuel-oil mixture to 40:1 from 16:1, full throttling 4 strokes all the time at mid-high RPM and does it much sooner than at 3/4 throttle so I suspect my main jet is probably too rich given I live at ~5000 feet altitude.
I have my carburetor pulled apart and measured my main jet and tried to find a set online but it seems like my main jet is a unusual spec. Calipers say the threading is M6x0.75 (6mm diameter x 0.75mm pitch) with a 5.5mm head diameter and a total length of 9mm with the head being 4mm long and the threading portion being 5mm long. The hole diameter is ~0.6-0.7mm I think but it's hard to tell even with calipers.
I've already tried playing around with the needle clip (even using tiny shimmies to fine tune it) but I've basically perfected all but wide open throttle. I've also drilled some holes into the stock air box but it's still pretty rich at full send.
Anyone know where to find a jet that fits the specs above? Any help you guys can provide is greatly appreciated. I really want to break 30mph!
Here's a picture of the jet for reference. Most listings I see, the head diameter is 7mm while the threading is typically M5 or M6 but with 0.8mm pitch.
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