Short answer: turn the fuel valve to ON, pull the choke down, leave the throttle alone, then give the pull start three or four short steady pulls. Once it fires, push the choke back off and let it idle about thirty seconds before you ride.
That is the whole thing. Most people who think their bike is broken have just missed one of those four steps, almost always the fuel valve or the choke.
Before the very first start
Out of the box there is no fuel in it. Bikes cannot ship with gas in the tank, so the tank is dry when it reaches you. Two things have to happen first:
- Mix your fuel. This is a two stroke, so it runs on gas with two stroke oil mixed in, at 25 to 1. Straight gas will destroy the engine. There is a full walkthrough in our 25 to 1 fuel mixing guide.
- Check the bolts. The bike ships sealed in the factory crate exactly as it reaches us, about 90% assembled from the factory, and you complete the last of the assembly yourself: handlebars, front wheel, fluids, and a pass over every bolt with a wrench, usually 20 to 30 minutes with the tools in the box. Go around every fastener, squeeze both brakes, and roll it a few feet before you ever start it.
The cold start, in order
- Fuel valve ON. It is the small tap on the fuel line under the tank. It has positions, usually OFF, ON and RES. Turn it to ON. If this is off, the bike will fire on whatever is left in the carb and then die a few seconds later, which is the single most common call we get.
- Choke down. The choke is the small lever on the carburetor. Down means closed, which is what a cold engine needs. A warm engine does not need it at all.
- Kill switch connected. If your bike has a tether or a kill switch, make sure it is in the run position. Some bikes will not spark at all without it.
- Hands off the throttle. Do not hold it open. The choke is already doing the job. Opening the throttle on a cold two stroke usually makes it harder, not easier.
- Pull. Short, firm, steady pulls. Do not rip the cord out to its full length and do not let it snap back. Three or four pulls is normal on a cold engine.
- Choke off once it fires. As soon as it catches, push the choke back up to the running position. If you leave the choke on it will run rich, bog and load up the plug.
- Let it warm up. Thirty seconds of idle before anyone rides it. A two stroke that gets ridden hard cold does not last.
Starting it when it is already warm
Warm engine, no choke. Fuel valve stays on, leave the choke up, and pull. Using the choke on a warm engine floods it, and then you are waiting five minutes for it to clear.
It fires, then dies after a few seconds
This is the most common problem and it is almost never the engine. It is fuel getting to the carburetor. Work down this list in order:
- Fuel valve. Is it actually on. Check it, do not assume.
- Fuel in the tank. Look in, do not go by feel.
- Choke position. If you left it down after it fired, it is drowning.
- The mix. Too much oil fouls the plug and bogs it. If the ratio has been changed around a few times, the carburetor may need cleaning out.
- Old fuel. Mixed gas goes off. If it has been sitting over a month, dump it and mix fresh.
It will not fire at all
- Kill switch or tether. Easiest thing to miss. Check it first.
- Spark plug. Pull it. If it is soaking wet it is flooded, so leave the plug out and pull the cord a few times to clear the cylinder, then dry the plug and refit it. If it is black and crusty it is fouled and wants replacing.
- Flooded from too many pulls. Choke off, throttle fully open, pull six to eight times to clear it, then start again from the top.
Set the speed before your kid rides
There is a governor screw on the carburetor. Back it off and the bike will barely move faster than a jog. Open it up a turn at a time as your rider gets comfortable. Full speed is 32 mph, and you decide how much of that they get, not the bike.
Common questions
Do I need to hold the throttle while pulling?
No. Hands off. The choke handles a cold start on its own.
How many pulls is normal?
Three or four cold. One or two warm. If you are past ten, stop pulling and go through the fires-then-dies list above, because you are now flooding it.
Why does it start and then die when I let go of the choke?
The engine is not warm enough yet. Push the choke halfway rather than all the way off, give it another twenty seconds, then take it fully off.
Can I use straight gas just once?
No. Not once, not for a minute. A two stroke gets all of its lubrication from the oil in the fuel. Straight gas seizes the engine, and that is not a warranty repair.
It still will not run.
Send us a short video of you trying to start it, from the fuel valve to the pull, at pluggedbycc@gmail.com. Nine times out of ten we spot it in the video.
Everything else
Step by step assembly video, fuel mixing, first ride tips, maintenance checklist and the full wont start walkthrough are all free at manual.pluggedby50cc.com.
Looking at your first one? The 50cc gas bikes are $300 with free shipping to all 50 states, out the same day.
Off road use only. Helmet and gear every ride, and an adult supervising.
Plugged by 50CC is an independent retailer. We do not manufacture, assemble, modify or service the bikes we sell. Every bike ships sealed in its factory crate exactly as it reaches us, about 90% assembled from the factory, and final assembly and setup are completed by the buyer. Off-road use only. Riders under 18 should always be supervised by an adult.