SteveCZ28

i havent heard of the serval cylinders...what exactly are they, and why should i look into them? kinda sucks i have to rebuild the entire top end now, but oh well, it woulda been fun to ride it as a 375cc. so are you reccomending i start out with fresh standard jugs/pistons and go from there??? EDIT: just looked up serval cylinders on ebay. i dont have a grand just to throw at the top end. or maybe you could correct me on what im looking for

thanks guys......also, being as the left cylinder is gouged really bad, would it be better to get another cylinder/jug and bore it to the size of pistons i have (obviously replacing the one that has shrapnel in it. im not sure how far you can bore a cylinder on these motors, is the only reason i ask, being as mine is already 1.5 over

the worrysome part for me is pulling thwe crank and not messing up the tranny, and shifting forks but yea like you say i have a manual so itll help me thru this. i wont have time till next weekend to tear it further down tho

i just checked it. most of the little pieces are not magnetic. but there are 2 bigger chunks that are. they almost look like a chunk of a ring tho

ive never tore a bottom end of a motor like this down before. good thing i have a clymers manual. ill attempt to tear down, and im thinking it would be smart to put new bearings/seals in down there just to eliminate that from a possible cause. i did kinda wiggle/rattle the rod on the left cylinder. it doesnt have any play or slop in it, so hopefully its good

nope all of the screws from both sets of reeds are present and accounted for

ok i tore into my shee today. pulled the motor as i was going to check the top end gaskets. pulled motor out, and pulled the head off...not happy with what i found. i now know why my left cylinder was acting up. something let go in the left cylinder. shrapnel all over the piston, and head. but the right (good) cylinder looked brand new...took jugs off, and found something cracked the rings on the left cylinder then welded them in to where they werent allowing compression to be made, as they were stuck in the grooves, and broken in a few places. once again right side was perfect. left jug has some really bad gouge marks. so atleast i know why its acting up, but now i need to know why it did this...hers some pics of what i found also i know i said it was a 20 over earlier, i just looked the piston numbers up again, their actually 1.50 over....and would have created a 375cc displacment. i wish it ran good enough for me to ride it more than 5 minutes and really know what this bike was about....now i am at stage one again and starting over right cylinder

idk why but when i click on that link all it does is take me to the home page for this site.

that does bring up another thing it will do time to time. itll start revving way high on its own, and ill hit the killswitch and it almost acts like its dieseling and running hot and combusting on its own with no speark, then will snap out then die.

im in greene,ia or northeastern iowa

can u give me a link, im not seeing this topic u speak of

tried to check compression but the tester was being dumb and wouldnt hold the pressure long enough to check it. head is a stocker, and it has a new head gasket. i might dig into the carbs. ill admit i kinda get worried when messing with jets. im fine with the floats and pins and what not.i did set the needles to the 2nd notch fro the top, so 2nd from the leanest it can be i believe. i still dont know how to do the leak down test on it, or how to mak the tester as was mentioned earlier in this thread by another poster. it does fire up instantly with some spray thru the carbs. yea i kick it soo many times i get a head ache...although i might try just pushing and pop starting it. or have a friend pull me behind my 3 wheeler.

i actually tore the completle top end off. checked the pistons, rings skirts, cylinders, and ports before i ever tried to start it, just to confirm everything. everything was indeed fresh when i got it....yes i can see the skirt thru the intake

yes i check spark time to time on it. it has spark evertime i check. swapped wires, does the same thing, and the plugs are brand spanking new out of the box. im the only guy around with a banshee, that i know of atleast

yes the stock cages still have their stops on them. how exactly do i do a leak down test. and what am i looking for here?

it also starts hard cold. itll take like 100-150 kicks. right when im ready to quit kicking, itll finally pop and start

yes i do

im just completly out of ideas on my shee and am really close to selling it. so i thought i would get on here in a last hope kind of deal on hoping to figure this out. ill bring you up to speed on my deal. i found a 1992 banshee with a 03 motor and plastics. got a good deal on it so i thought i would take a crack at it. the previous owner told me he was in the process of doing a top end in it. claims he bored the top end 20 over. i got it home tore the top end apart looked up numbers on the pistons and they are indeed 20 over wiseco pistons. had no run time on them at all. so over a period of 3 months i got some little odds and ends here, and finally went to start it. got it to start, but would only run on the right cylinder. wrenched and wrenched, and found out the left dead cylinder was cracking my delta 3 reeds, which got really expensive really quick buying replacement petals. wrote delta, and they had told me that its getting too much fuel or excess pressure in bottom end. i found the crank vent was clogged, cleaned it out and now got the left cylinder to pop every once in a while, but was still cracking reeds. a friend of mine reccomended switching the carb from the right to put on theleft and vice versa. kicked it, and it now ran on the left cylinder and was dead on the right so i got on ebay and got a new used set of carbs, put them in, and it would run on both cylinders if the choke was on halfway all the time. if i shut the choke off the left cylinder would once again go dead. so thats where im at today. still dead on left cylinder unless i run it with half choke, but when trying to ride on half choke it doesnt have very much power. so if i sht choke off and keep throttle bout half way both cylinders fire and she runs hard as hell, but if i let off the throttle at all, it goes dead on left cylinder and chugs and bogs really bad. i tried switching reeds out for a set of stock reeds with boyeson petals, and stil have same problem. im out of ideas on this thing, and dont know what to do at all. the guy i got the carbs from said he had it jetted for toomy t5's which i have, and also k&n filters, which i also have. i dont know a ton about the jetting, as i havent disassembled the carbs to confirm. also when i mess with the air mixture screw it doesnt seem to affect how the left cylinder runs at all.....thats where you guys come into play. i know this is a rather long read, but im just about done with this thing and about to part it out, but wanna give it one last shot, hoping it could be something i could still fix rather easily, instead of kicking my own butt down the road