Engine locked-up, need advise.

is this a general consensus? 40 more cc is about 20% bigger.
20% is pretty significant, are you saying that a 20% bigger bore does not translate to any noticeable power increase? im really surprised.
awk, im not questioning you, just trying to make sense of it all.



can someone with .040 bore kit share their thoughts.
 
.40 over the standard bore is not 240cc.
To get 240cc displacement you must use a larger aftermarket cylinder or sleeve.
By boring .40 over you will NOT feel any difference whatsoever.
An extra 40cc's though, you will.
Your better off getting your stock cylinder ported. A ported stock cylinder will beat a non ported 240cc cylinder.

EDIT: Check these links

Vito's 240

LA Sleeve 240
 
is this a general consensus?

its a proven scientific fact. it in fact will increase HP, but barely any. im sure you would be able to see the difference on a dyno a little. but if you were to ride one blaster that is stock bore, then jump on one that is .080 over you could not tell the difference by the seat of the pants. IMO, it is not worth doing unless you have to, you are just decreasing the overall life of your cylinder. other mods, like pipes, porting, carbs, head mods, reeds, ect. ect. are much better options to pick up some HP.
 
some years back i ported a regular 5hp go-kart engine, and it was fairly simple.
trying to figure out how many of you if any have ported their own blaster engine. or if its recommended that you leave it to the pros due to complexity.
 
If you have a steady hand you could clean the cast imperfections. I wouldn't. Changing port timing without knowing what your doing can f**ck stuff up.
 
some years back i ported a regular 5hp go-kart engine, and it was fairly simple.
trying to figure out how many of you if any have ported their own blaster engine. or if its recommended that you leave it to the pros due to complexity.

porting a 2 stroke cylinder is a much complex process than what you have done with the go cart. if you need a detailed explaination maybe someone else will chime in. or you can search this site, other forums, or google.
 
ok fellas, took the top end off the engine this weekend and it was not a pretty sight.
i removed all the top end bolts and this point the engine was still locked up. decided to put some penetrating oil down the cylinder and wiggle the jug and it came right off.
piston was partially melted on top, looked like it had been arching with the spark plug. looks like some of the aluminum from the piston melted down the cylinder along with some the chips from the arching. surprisingly the cylinder is not in as bad of a shape as i had expected. most of the aluminum smeared dry along the side of the piston and cylinder. i was able to get all of it out by scraping lightly with a screw driver and WD40.
went back to check on the inside of the crank and realized the rod was still locked up. i looked down the crank and some of the aluminum shavings were visible.
i completely removed the motor of the atv and placed on the bench. i put a ratchet on the stattor side and cranked it, thus moving the piston rod.
i was able to break it loose but, on the down stroke as the piston reaches the very bottom of the crank, there seems to be metal shavings that are still wedged between the crank and crankcase wall, it doesnt spin freely on that spot, it kinda grinds on that part of the cycle.
i havent started yet to take apart the crank. but, i know i will have to. once i get the crank apart i can take a better look and see whats going on. i dont think theres any damage but there are also pieces of smeared dry aluminum on the crank that have to scraped and cleaned off. ill have some pics for you guys later on.
i will have my hands on a puller today or tomorrow. is there anything i need to know about pulling that crankcase apart. please let me know your thoughts

thanks

oz
 
dont force it any more to turn it over..wosrt case scenario you put a hole in your cases doing that if one of the peices hits just right. if anything it is getting all gauged up.
 
dont force it any more to turn it over..wosrt case scenario you put a hole in your cases doing that if one of the peices hits just right. if anything it is getting all gauged up.

it actually turns over all the way, the one spot is grinding a little. but, it wasnt forced to break it loose. im pretty sure the're no wholes on the case. there might be some minor, very minor gauging. the aluminum is so much softer that it really kinda got flattend out.
either way im not doing or going to do anything thats going to cause more damage. waiting for the puller to pull the gears out and clean the crankcase.
 
ok fellas, took the top end off the engine this weekend and it was not a pretty sight.
i removed all the top end bolts and this point the engine was still locked up. decided to put some penetrating oil down the cylinder and wiggle the jug and it came right off.
piston was partially melted on top, looked like it had been arching with the spark plug. looks like some of the aluminum from the piston melted down the cylinder along with some the chips from the arching. surprisingly the cylinder is not in as bad of a shape as i had expected. most of the aluminum smeared dry along the side of the piston and cylinder. i was able to get all of it out by scraping lightly with a screw driver and WD40.
went back to check on the inside of the crank and realized the rod was still locked up. i looked down the crank and some of the aluminum shavings were visible.
i completely removed the motor of the atv and placed on the bench. i put a ratchet on the stattor side and cranked it, thus moving the piston rod.
i was able to break it loose but, on the down stroke as the piston reaches the very bottom of the crank, there seems to be metal shavings that are still wedged between the crank and crankcase wall, it doesnt spin freely on that spot, it kinda grinds on that part of the cycle.
i havent started yet to take apart the crank. but, i know i will have to. once i get the crank apart i can take a better look and see whats going on. i dont think theres any damage but there are also pieces of smeared dry aluminum on the crank that have to scraped and cleaned off. ill have some pics for you guys later on.
i will have my hands on a puller today or tomorrow. is there anything i need to know about pulling that crankcase apart. please let me know your thoughts

thanks

oz

well you did say you got it turning by using a ratchet and socket on the flywheel, that is force..i was just trying to help you. hope you get it going.
 
it actually turns over all the way, the one spot is grinding a little. but, it wasnt forced to break it loose. im pretty sure the're no wholes on the case. there might be some minor, very minor gauging. the aluminum is so much softer that it really kinda got flattend out.
either way im not doing or going to do anything thats going to cause more damage. waiting for the puller to pull the gears out and clean the crankcase.

When you do get the cases apart, pay particular attention to the big end, and shaft bearings because there could be little pieces of shrapnel in them.