KB_UK
Member
- Local time
- 1:00 AM
- Joined
- Oct 11, 2016
- Messages
- 118
Hey there. I just built a 66cc bike and I can't get it to run for more than a few seconds.
I have spark. I have compression too, because its harder to pedal when I let go of the clutch. As it's a brand new engine I used a 5L petrol can to mix 4L of petrol with 250mL of Castrol 2-stroke oil, for 16:1 like it says in the manual.
I pedal up to some speed, let go of the clutch, and it kicks in, but it doesn't idle. I can give it some gas and it'll rev up a bit, but over time it becomes less effective. I'd say it runs for about 30 seconds, and the power gradually drops off. In the end I have to pedal it to keep the engine turning over, even if I give it full throttle.
The behaviour is the same no matter if I start with the choke or not. It's all standard parts as come with the kit on ebay. Normal NT carb, I haven't messed with the idle screw or anything yet. There's no obvious rookie mistakes like an upside down carb.
One thing I'll say I noticed is that the throttle cable seemed very very slack when I installed it. I had to unscrew the barrel adjuster very far to take it up. I watched the carb needle go up and down when I did that, so it looked right, but I'm not sure.
I'm sure there's something I've done wrong, maybe the carb, I don't know. I thought it was best to ask the wise elders before I start tinkering, in case I make it worse.
I have spark. I have compression too, because its harder to pedal when I let go of the clutch. As it's a brand new engine I used a 5L petrol can to mix 4L of petrol with 250mL of Castrol 2-stroke oil, for 16:1 like it says in the manual.
I pedal up to some speed, let go of the clutch, and it kicks in, but it doesn't idle. I can give it some gas and it'll rev up a bit, but over time it becomes less effective. I'd say it runs for about 30 seconds, and the power gradually drops off. In the end I have to pedal it to keep the engine turning over, even if I give it full throttle.
The behaviour is the same no matter if I start with the choke or not. It's all standard parts as come with the kit on ebay. Normal NT carb, I haven't messed with the idle screw or anything yet. There's no obvious rookie mistakes like an upside down carb.
One thing I'll say I noticed is that the throttle cable seemed very very slack when I installed it. I had to unscrew the barrel adjuster very far to take it up. I watched the carb needle go up and down when I did that, so it looked right, but I'm not sure.
I'm sure there's something I've done wrong, maybe the carb, I don't know. I thought it was best to ask the wise elders before I start tinkering, in case I make it worse.