83 250r Locked up PICS--*FIXED!

[twgranger]

I cant believe that thing actually ran!!!!!

[smyers33]

So it will need to be bored eh... I'll go take the piston out and comeback with some more info...Thanks

[smyers33]

Sanded the piston, and found out its a Wiseco 70.00mm. I belive that is stock bore. Sooo.... I will have to take it to a machine shop and just get it bored .10 over? Syko, what do you mean there needs to be more clearance. Also are we sure that the damn razor blade is what caused this? If so how? Did it just mess up the Oil, Gas, and Air mixture?

[Billy Golightly]

Holy crap dude, no offense but you shouldn't have even cracked a nut on that topend with all that mud dirt and grass around it I can see somes already fallen down inside the crankcase in the other picture. VERY VERY carefully bolt the topend back down and clean that crap off before a clod falls in somewhere you didn't notice. #1 thing that gives long engine life is cleanliness, it can also be the #1 remover of engine life.

Once you get everything cleaned you can take it back apart and get the circlips out with either an icepick or something small and pointy like the end of a pocket knife or a fork. Rag up the crankcase though so when it comes out it dont fall in.

[smyers33]

I know I prolly shouldn't have, but I was just caught up in the moment and wasn't thinking. I had the motor shining before I took it out this morning and then it got muddy. I do take great care of my machines, and wash them after almost every ride. I've had a towel down in the crank ever since I pulled the cylinder. I am going to flush out the bottom end after I get the piston off. I read somewhere that you can use kerosene or diesal. What should I use to flush it out?

[SYKO]

thats not the stock bore on it, but you should have 1 or 2 more bores left, depending on the amount of damage done to the cyl, also dont buy a piston untill you know how much they plan on boring to remove the damage from the cyl. on an air cooled motor there needs to be more piston to cyl clearance, less on a water cooled, exspecially if you are goint to use a wiscoe piston, the razor blade, well I dont see it causing any of the damage, the only thing I could see it doing is blocking some of the air, creating a rich mixture, so it didnt lock up from being rich, what did your spark plug look like?? the only way it could have leaned out was a leak on the head, becouse you said there was no gasket. you will end up only having about $160 in it if you do the work (i.e assembly) wich isnt bad, be glas is wasnt a 4 stroke that droped a valve and broke a timming chain!

[Billy Golightly]

When you get the piston off, if you look under the bottom side of it all the way up under the dome, if there is any burnt "ash" looking build up there its a good indication you were, or were on your way to lean air/fuel mixture. A black and dark brown stain on it is normal but the ash is not.

[smyers33]

Alright Billy thanks for that tip. Syko, The plug is nasty, black and oily, I wish I would've changed it when I got it. It is a weird brand too. It's a Denso W20FP-U.
Also here is a pic of the head. It seems fine, with a tiny little scrach in it.

[SYKO]

man from what I can tell the electrode on the plug looks lean! and oily on the threads, was it installed tight in the motor??

[smyers33]

The electrode is a grayish color, and the threads are black oily. Actually it wasn't all the way tightened. Seemed too easy when I took the wrench to it.

[oldsking86]

Dude that brings back memories on a guys chevelle I worked on. It was a 1970 with a BB 396, gorgeous car!! Well the guy brought it to use for a cam, carb, intake, MSD ignition and some more stuff.. Anyhwo we took the intake off and in the valley sitting there was a SCREWDRIVER!!! THe car was running a bit rough when we got and that was the main problem right there lol

Hopewfully you get that sucker squared away and running too! Good luck !

[Erics350x]

i would rebuild the carb to be safe.

[200x Basket]

you were way lean. the seized the piston. if you had no head gasket you may have been sucking air there or it is jette to lean. I would buy a carb kit and clean/ rebuild the carb. fresh bore and new piston with a new gasket kit. after all of that i would look into doing an air test to check for leaks.

i would also check the head is nice and flat. to do you need a thick pain of glass and some 600 grit wet sand paper. place the paper on the glass and then place the head on the paper. lightly sand in a circular motion until the whole gasket surface is shiney.

[smyers33]

Well I cleaned the carb, all the jet holes are and were open, I blew them out with the air compressor. You can see where there are nic's and scracthes in the carb from the razor blade. They are all small and I don't think they should affect anything. I guess I'll just order this carb kit http://denniskirk.com/jsp/product_ca...101&mmyId=5899 since its only 15 bucks. I wonder if they old owner didn't rejet after adding the boyseen reeds and exhaust pipe? I don't know. I got the circlips out, but now how do I take the wrist pin out? I'm going to be calling around and asking some cycle shops where to get my cylinder bored at, and hopefully take it their this week.

[SYKO]

you just got to push the wrist pin out, sometimes it can be a pain, but it will come out, but whatever you do dont use a to push it out!!!