# 49cc help



## booms (Sep 8, 2006)

hi, i have a 49cc pocket bike and i cant figure out why it wont start. ive cheked for spark and it has spark, its got good compression, i put straight gas in the head itself thinking it would at least fire, i tried 1:30 mix in the tank and straight in the head.(its supposed to be 1:25) when you pull the recoil and give it full throttle it sounds like it wants to start but it just doesnt. ive tried unhooking the kill switch, choke on, choke off, fuel on, fuel off. Can anyone help!?!?


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## jgj6331 (Aug 9, 2006)

Check the exhaust to make sure it's not blocked - remove and clean out the muffler.


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## Herrmanator8 (Apr 29, 2007)

first off, the muffler doesnt have much to do with it. try taking out the air filter and spraying "engine starter fluid" directly into the carb. make shure the gas ratio is whats directed in the manual, dont make up your own. make shure your using 2 stroke engine oil only. 4 stroke engine oil will kill it.


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## 30yearTech (Sep 14, 2006)

If there is restriction in the exhaust, you bet it won't start and if it does will not run very well. Check for an air leak into the crankcase, if you are getting spark, have compression then it should at least fire off with a prime, but if you have a big air leak into the crankcase most 2-cycle engine will not start and may not even pop. 

Ignition timing can also prevent an engine from firing up.


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## oscaryu1 (Mar 25, 2007)

Herrmanator8 said:


> first off, the muffler doesnt have much to do with it. try taking out the air filter and spraying "engine starter fluid" directly into the carb. make shure the gas ratio is whats directed in the manual, dont make up your own. make shure your using 2 stroke engine oil only. 4 stroke engine oil will kill it.




i may not be right but i think in another post that it said something about not using starter fluid in 2 cycle engines.. i may be wrong though


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## 30yearTech (Sep 14, 2006)

oscaryu1 you are correct!

Starting fluid generally contains ether. It has no lubricating properties and is very explosive, excessive pressure from ignition can blow out the crankcase seals in a 2 cycle engine. It's not recommended for starting a 2-cycle engine.


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## oscaryu1 (Mar 25, 2007)

ouch! no wonder my 2 cycle wont start again.. shouldnt have used it...


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## katorat (Apr 21, 2007)

i put carb cleaner in my pocket bike engine that would not start but my problem was the carb wasnt really tuned put that carb cleaner will start any engine i swear. just spray some in the carb and try it. it worked for me


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## oscaryu1 (Mar 25, 2007)

but like 30year said theres a chance that you'll blow out the crankcase seals... so it can work, but theres a chance that something'll go wrong


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## geogrubb (Jul 28, 2006)

There is a multitude of explosive stuff that people use to start engines, most of which shouldn't be used, some people swear by using WD-40, a long time ago I used laquer thinner in a 6volt Ford flathead, I got desperate once and dumped some Everclear 190 proof straight grain in the carb, it didn't start but when it backfired thru the carb it shot the prettiest blue flame about 2 feet in the air you ever saw, so be careful and don't hurt yourseld or someone else. Have a good one. Geo


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## oscaryu1 (Mar 25, 2007)

Geogrubb: Has anyone use AXE or Spray paint or oil before? :tongue:


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## 30yearTech (Sep 14, 2006)

I use carburetor spray cleaner to start engines all the time, it is not as explosive as gasoline so you don't have to worry about that. You don't want to run a 2 cycle very long with it as it does not lubricate.

I really miss the days when propane was used as a propellant in WD-40 that made a great starter fluid.


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