Is your piston put in backwards?

inspectorcritic

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... or coulld it be Gasbike sabatage took 7 months to argue a deal. The kiss button that prevents the ring from sliding around is on the front where it now slides the slit over the exhaust port where it could expand snag and snap and snag and wear out also its not good for the 2 stroke intake and export system and may have some power loss. Take a look at your piston you might just take off the exhaust look in with a flash light I would like to know, there is a utb motor pro who claims this.
 


butre

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I've never paid much attention to the way they came, the first thing I do with any new engine is tear it down completely and clean up the casting and true the crank. I do know that the ring ends are supposed to be on the intake side.
 

zippinaround

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i,ve come across pistons with the arrow stamped on the wrong side , but the ring ends were still on the intake side so just left it , most likely a tired chinaman or maybe he just thinks that is the right side to stamp the arrow?
 

sp1ke

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i got a new 66cc engine today the piston stamp is definatly wrong way ive not tore it apart yet but the chamber and head look far better and the intake and exhaust ports are bigger and can be made bigger a few parts were diffrent i think ive got better parts this time will be intresting taking it apart
 

butre

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i,ve come across pistons with the arrow stamped on the wrong side , but the ring ends were still on the intake side so just left it , most likely a tired chinaman or maybe he just thinks that is the right side to stamp the arrow?
they're made in several different factories each with slightly different tooling. it's pretty well known that you should ignore the arrow
 

inspectorcritic

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i got a new 66cc engine today the piston stamp is definatly wrong way ive not tore it apart yet but the chamber and head look far better and the intake and exhaust ports are bigger and can be made bigger a few parts were diffrent i think ive got better parts this time will be intresting taking it apart
I don't see why or how they dare take a new engine apart you loose your arrantee for messing with it here is a pic of my shanghai motor ith piston put in backwards did it cause the scoring?
 

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sp1ke

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Dec 16, 2016
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I don't see why or how they dare take a new engine apart you loose your arrantee for messing with it here is a pic of my shanghai motor ith piston put in backwards did it cause the scoring?
i never use mechanics i have a veriety of reasons 1 being i do a better job then most of them and a warantee is only worth the original product i want to mod it so warenty void and im not bothered ill take rubish and make it awesum ill allways be there to repair it :) and far better n faster then a warantee

i tore my new engine apart today and it was just stamped wrong but ring joins face carb inlet as expected i wouldnt want to run it backwards so a good thing to check



inspector what way are your rings pointing should be like mine facing carb on first look from the photo id say its more likely too high compression causeing excessive wear as a guess

if the ring slits are facing the exhaust it could snag on the exhaust port and cause damage to rings piston chamber spark plug and head ( possibly metal breaks and starts flying around bouncing off everything then bits of that can get in to your bearings as well )
 
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zippinaround

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I don't see why or how they dare take a new engine apart you loose your arrantee for messing with it here is a pic of my shanghai motor ith piston put in backwards did it cause the scoring?
to me it looks like too high compression , but also that nibbling around the top of cylinder would be a good indication your bottom bearing was ready to go , so may have contributed especially if the scoring is mainly on the top end of cylinder. but would be interesting to know if your ring ends face the intake or exhaust .
 
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