What Happened to this thing???

[blacknblue#2]

Ok i had this banshee dropped off yesterday that was locked up. I tore it apart and the jugs are fine. I look to find that the left side cylinder is all chewed up tho like something has been in the banging around but nothing was in there. So i pulled the jugs off to find out that the left side of the crank is locked up. I know that we have no clue what really happen but does anyone have an idea what may have happened???

http://i161.photobucket.com/albums/t207/aerospac/005-14.jpg

http://i161.photobucket.com/albums/t207/aerospac/006-14.jpg

[Dinner]

You say the piston, rings, bearings, etc are fine? Looks like my old head when I got my banshee re-built. That was probably caused by the last blow up of some sort where pieces of the piston, etc actually came off and wrecked the head. So instead of putting a new head on when he got it rebuilt and bored .020 over, they just put the stock one back on. Didn't even bother to re-chamber the head:eek2:

[400exrider989]

well to have a crank lock up your usually have to have something fall in there to jam it, what did the pistons look like?, by the looks of the plugs it was lean, possibly a air leak somewhere

[blacknblue#2]

No No the piston looks just like the head......but the jug itself is fine. Something had to be in there i thought too but i didnt see anything when i pulled the head off....that dont mean anything though.......I called the owner about an hour ago and he said do what has to be done so im ordering a complete rebuild kit and doing it all, I dont really know what to do with this head tho?? He said clean it up knock the burrs off and put it back on. I wouldnt take that route if it was mine but how can i tell him no when he owns it lol..........Any tips or tricks i should know about rebuildin a shee. I have never been this far into one of these engines so this will be a learning experience. im down to splitting the case now and i called it quits for the night

[400exrider989]

well if you had a crank lock up then splitting the cases is a must, get the old crank out, put a new one in that has been trued and welded, buy all new seals, you said your doing a complete top end which is good, i would not recomend using that head, unless you want to get it rechambered and shaved which would cost more then buying one off ebay, something must have got into the motor, if the piston looks the same with no hole or chunk missing then it must have had some dirt in there, but i dont know, the plugs kinda look leaned out, w.e the fact is do it right and do it once if its your first time then take your time, when putting the pistons onyou well want a clean rag stuffed in the crank area so nothing falls in and makes your day a living hell, good luck

[blacknblue#2]

Thanks man........ive done full rebuilds on 5 450Rs and 2 400ex but this is my first full done Shee....I noticed that the cases split differently which looks like it might be a good thing maybe i wont have gears fall everywhere haha. but yeah i ordered a full wiseco bottom end for him along with a full wiseco top end kit. I told him i was gonna look on ebay for a head so i will try to pursuade him into doing it right and buying a head. He was already had me spend this much, whats a little more

[CSR400EX]

the banshee cases split horizontally and the tranny stays in the bottom half so no gears and washers going everywhere lol. definitely looks like it was run lean. what kind of mods does the bike have??

[blacknblue#2]

The bike is bored .040 with full fmf exhaust and a pro flo intake.............one reason it looks lean is because they are brand new plugs..........When he dropped it off he told me he put new plugs in it but had no luck..............i didnt want to be a complete *** but i was thinking dude the kicker is locked like a wedge plugs have no possible way of helping this quad hahaha

[CSR400EX]

lol, i woulda like to seen the plugs that were in it when it blew. that would help out with determinig what happened. you wouldnt know what size jets he is running do you??

[blacknblue#2]

No man not yet i dont. The parts should be in the beginning of next week. so while im waitin on them this weekend i am gonna clean the carbs up and check the jetting on them. i kinda hate to mess with the jettin on twin carbs haha............i had a Shee back in 02 and i just spent the 500 bucks and put the trinity single carb on it to save me the jetting hassle lol

[CSR400EX]

most of my buddies go with PWK air strikers (sp) or Lectrons. they all got some nasty shee's, but its great to see the look on their faces when i brought out my lil 4 poker and kept up with them all:cool:

[Dinner]

Originally posted by CSR400EX
most of my buddies go with PWK air strikers (sp) or Lectrons. they all got some nasty shee's, but its great to see the look on their faces when i brought out my lil 4 poker and kept up with them all:cool:

For what this fella has done to the motor. He does not need Air Strikers nor Lectrons...

[Mxjunkie]

I'd say it lost a c-clip for the pistion and it wondered it's way up there.