OBR 30.5 converting to reed?

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I'm getting allot of mixed comments about this. The general consensus seems to be that this is normal for OBR 30.5cc engines and other people have this issue. I'm guessing that even know that free porting isn't good, it's something that comes stock with general 30.5cc engines of this caliber. Sucks but atleast now I know there isn't anything wrong with the port job.
 
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Troopermaniac said:
I'm getting allot of mixed comments about this. The general consensus seems to be that this is normal for OBR 30.5cc engines and other people have this issue. I'm guessing that even know that free porting isn't good, it's something that comes stock with general 30.5cc engines of this caliber. Sucks but atheist now I know there isn't anything wrong with the port job.
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I've only ever heard one guy say freeporting was a good idea. His name is Kevin.....
 
Can you get a measurement of the free porting? I've done a bit of researching and it seems a .005-.010" gap, won't hurt performance too much, however not desirable, because you could have 1 of 2 outcomes. Either you will loose fresh fuel air mix out the exhaust, or suck in exhaust gas back into the crankcase, either way your looking at some sort of net loss in power, even if it is considered "normal" for a given engine. It seams it would be most at a disadvantage in a reed type engine, due to a certain amount of negative pressure needed to open the reed petals, this would give the propensity for spent exhaust gasses to be sucked in rather the just a marginal loss of fresh fuel/air mix out the exhaust. Now I would think the effects would be most noticeable at lower rpm, ad the piston speed is relatively low giving greater time for losses. Either way I'm interested to hear what they have to say on the matter.
 
Seandonato73 said:
Can you get a measurement of the free porting? I've done a bit of researching and it seems a .005-.010" gap, won't hurt performance too much, however not desirable, because you could have 1 of 2 outcomes. Either you will loose fresh fuel air mix out the exhaust, or suck in exhaust gas back into the crankcase, either way your looking at some sort of net loss in power, even if it is considered "normal" for a given engine. It seams it would be most at a disadvantage in a reed type engine, due to a certain amount of negative pressure needed to open the reed petals, this would give the propensity for spent exhaust gasses to be sucked in rather the just a marginal loss of fresh fuel/air mix out the exhaust. Now I would think the effects would be most noticeable at lower rpm, ad the piston speed is relatively low giving greater time for losses. Either way I'm interested to hear what they have to say on the matter.
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.008 inch
 

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Seandonato73 said:
What does that mean pecker head?

Ah well at least it's not terrible then, within the parameters I found ad "acceptable". I would 100% be looking into that piston mark is talking about though.
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Imma see how it runs first. Problem right now is that the piston I have is extremely modified. Extensive amount of work has been done to it.
 
Rep732 said:
Thats blasphemous :oops::LOL:
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Hey you guuuuyyyssss!!!!!...... I agree😳🤣🤣🤣🤣🤣 Yaaaaarrrr!!!
barry clifford pirate GIF
🤘🏴‍☠️🤘
E...word!!
No GIF
 
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