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Blaster engines runs backwards

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Old Sep 9, 2008 | 11:00 AM
  #1  
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Default Blaster engines runs backwards

Hello All, I bought a spare blaster for parts. I was mostly interested in the engine. The previous owner( BUTCHER) banged on the crank to remove the flywheel( BROKEN INTO MANY PIECES). Well he sold it to me and I put my working stuff on the new frame and once I got the bike to fire, it ran in reverse ( put it in gear and back you go). Can someone explain this issue? I found no quick hits when I searched the forum

Thanks
CHUCK
 
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Old Sep 9, 2008 | 12:23 PM
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Default Blaster engines runs backwards

Humm find this hard to believe.
 
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Old Sep 9, 2008 | 12:55 PM
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Default Blaster engines runs backwards

Two stroke motors can easily run backwards depending on ignition timing setting. If set too close to top dead center then you won't have proper power but motor can run either way. I owned a 1973 Bultaco Alpina 2 stroke motorcycle for enduros that would occaisionally light off backwards when coasting backwards to get out of some nasty section and then releasing clutch. So hang on or get off.
 
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Old Sep 9, 2008 | 01:04 PM
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Default Blaster engines runs backwards

Well I see it this way, if you are kick starting it in one direction and then it fires up in the other direction when its really turning the other.

I do know that a two-stroke diesel engine (Detriot Diesel) will start in any direction but you have to rotate the engine in that direction in order for that to happen.
 
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Old Sep 9, 2008 | 01:21 PM
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Default Blaster engines runs backwards

Kick start ratchet will only allow motor to be kick started forward. You need to either coast backwards, or turn motor backwards with tires, or with some other mechanical system other than kick starter, to rotate motor backwards.
 
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Old Sep 9, 2008 | 01:33 PM
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Default Blaster engines runs backwards

I agree, so could this person be pushing his blaster in reverse???????
 
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Old Sep 9, 2008 | 01:39 PM
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Default Blaster engines runs backwards

Hello All,

I am not starting it backwards but there is alot of gas and starting fluid going on. I had 2 carbs and rebuilt a second one because the first did not work right and the dle seems to be fine. I will try again today after sitting. Compression is 120.
 
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Old Sep 9, 2008 | 02:03 PM
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Default Blaster engines runs backwards

Compression seems a little low and starting fluid and reed cages don't mix. Check you reeds for cracks.
 
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Old Sep 9, 2008 | 03:07 PM
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Default Blaster engines runs backwards

Hello Ernie,

What do the reeds exactly do.I do have a second set I can try. What's your thoughts
 
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Old Sep 9, 2008 | 03:27 PM
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Default Blaster engines runs backwards

ok, So what is a symptom of a bad reed valve in a blaster configuration?



Reed valves are commonly used in two-stroke engines to control the fuel-air mixture that is admitted to the engine crankcase. As the piston rises in the cylinder the resulting vacuum opens the valve and admits the fuel-air mixture. As the piston descends, it raises the crankcase pressure causing the valve to close to retain the mixture and pressurize it for its eventual transfer through to the combustion chamber.[1]
 
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