completely f*cked

[NOVIS]

when i rebuilt the top end after my brother blew it up it ran fine, but we were using the old spark plug which had some filings on it so my dad said not to use it. he gave me a new br9es that he had laying around and assured me it would be fine. i wouldnt have done this if it was me but my dad said i would be fine. after a while of running it it started backfireing so i shut it off and put it away. then i got the right spark plug and it semed to run good again, but i noticed it didnt feel like it had as much compression, but my dad said it was becaused i was used to kicking the banshee. so my brother took it out again and it died and he pushed it back.i took it apart and the piston was shattered on the intake side and i was like FUUUUUCK!! but it looked like all the peices stayed out of the case. i wanted to make sure and everything so i took the motor out. when i picked it up i looked into the hole at the crank and i could see light... i waved my hand underneath it and saw my fingers then i flipped it over and there was a hole with a peice of piston sticking out of it. but the worst part was the hole was evenly divided on both sides of the case so im guessing it pretty mangled if it was running without oil. i feel so bad for my bro, i give him the blaster and his first ride he blows it up, so i fix it and now this!!!

 

[brandoz28]

nothing to do with the spark plug


but that sucks

 

[super noober]

Re: completely f**cked

thats really sh*tty man, i really dont think the plug had anything to do with it though. tiem to scrounge egay for some cases

 

[02yamaturd]

damn man that really sucks....hopefully you can find a case for cheap....

 

[NOVIS]

Re: completely f**cked

nothing to do with the spark plug


but that sucks

what do you think made it backfire then. just random or what? cuz i was thinking if the plug wasnt exploding the gas properly everytime it could build up and then when it did explode it made it backfire.

 

[brandoz28]

i'm guessing air leak, or excessive piston/wall clearance

 

[NOVIS]

oh ok .

 

[brandoz28]

and what kind of piston was it?

 

[NOVIS]

yamaha, not aftermarket or anything.

 

[brandoz28]

basically the issue is a cast piston with too much piston to wall clearance. same problem that guys have with a heavily worn cylinder.

should have bit the bullet for a bore/hone/wiseco

 

[NOVIS]

oh man if it was ME doing it for ME i woulda got the bore and a wiseco piston and probly woulda sent it out for porting lol.

 

[brandoz28]

now its going to cost way more with new cases and rebuilding the bottom end than it would have to do the bore/hone and go to the next size piston


if you can't afford to do it right the first time, can you afford to do it again?

 

[phragle]

Master Brandoz, the force is becoming strong with you young jedi, trust in the force for it is wisdom.

 

[NOVIS]

ill probly try to find a decent deal on a full motor, or at least one with a blown top end.

 

[scotj77]

That could work but you are opening a whole new can of worms you have never even seen before. I would replace the cases, crank, bore the jug, get the head rechambered, weisco piston. might as well go 3 mill stroker while your there. not much more money. this way you know exactly what you have and no NEW suprises

 

[brandoz28]

Re: completely f**cked

Master Brandoz, the force is becoming strong with you young jedi, trust in the force for it is wisdom.

i'm still but an apprentice master phragle.

 

[NOVIS]

Re: completely f**cked

That could work but you are opening a whole new can of worms you have never even seen before. I would replace the cases, crank, bore the jug, get the head rechambered, weisco piston. might as well go 3 mill stroker while your there. not much more money. this way you know exactly what you have and no NEW suprises

dude my brother is 14 and no job, not a chance in hell he can afford that. if i can at leat find a good deal on a used bottom end, i could probly get that cheaper then a new crank. everything still seems ok tho so i might just get the new cases and be good. plus a new top end.

 

[brandoz28]

you can get a new crank for about 160 bucks with the crank bearings and seals

 

[phragle]

Do it right. you dont want him worrying about it and you dont want to put him in a position wherehe has to do it again.

 

[scotj77]

Right on man! I have taken shortcuts in the past and they ended up biting me in the ass later on. He might only be 4 but this would be a good way for him to learn how to build his quad the right way and not shortcut in the future and end up with broke cases. Maybe his big bro could help him out. it will take time just buy one part at a time. he can push a lawn mower right.