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The grandkids Predator 50 is giving me a fit again. They were riding it and it just shut down. It appears to not be getting fuel. I thought it might be the carb, so I put a brand new one on it (had the extra carb laying around), but it still doesn't start. If I hold the throttle wide open, it will eventually sputter and run for about 2 seconds. I know these little ones are fairly basic, but 2 strokes still perplex me. What is the function of the Reed valves, and do they go bad ? I can't think of anything else.

I know it's getting spark.
Compression is 120 psi after 3 spins.

 

Never had to replace reeds in any of the little ones from the time they came out until the 4 strokes replaced them,but you can check their condition if you wish.Reed valves open and close in accordance to how much throttle/vacuum is needed. Reeds came out as a great update on the plain old piston port engines of the past that would bog if too much fuel was dumped in at one time.They allowed for a good increase in power and better low/mid range throttle response. First though if you're not blocking the air tube with your thumb,try that and see if it cranks up. These little ones just didn't have enough vacuum to pull fuel in when cold or sitting for a while. Had an "in house" bulletin on this from Polaris to do this as the electronic chokes and even the manual chokes at times were useless.Once cranked,usually no problem starting after that.

 

I agree, hand choke that baby.
Reeds can crack but it's rare.

 

Thanks guys. It has a manual choke, and I've tried to "hand choke" it several times. Still no go. I've found a couple of you tube vids that explain some Reed valve failures, how to check them, etc. I'll try to pull them this week and take a look. Honestly, I can't think of anything else it can be. The engine was totally rebuilt last year, except for the Reeds. I didn't replace those because the mechanic said they never go bad. The grand kids only got about 24 hrs of riding since the rebuild.