1981 Honda ATC 200 Topend Blew

[Pierce1989]

Hey everyone. My 3 wheeler was spitting white smoke everywhere and then seized. I am able to turn the crank with the side nut with a socket so it's time a for a topend rebuild. I've never had to do this type of work before so a little nervous/excited. If the piston rings were bad and the engine was running hot and seized, I'm wondering what all I need for the rebuild. I see piston kits on ebay for my trike, are these okay to buy? Wiseco piston rebuild kits. Should I just buy a new cylinder with the kit? I've seen where the cylinder will come with the new pistons on ebay but I can't find it anymore (will continue looking). These are already correct size for the piston I'm assuming. But I can keep my old cylinder head? While I have everything apart, what else should I do besides adjusting the valves and timing chain tension? Thanks for the advice!

[yaegerb]

Hey everyone. My 3 wheeler was spitting white smoke everywhere and then seized. I am able to turn the crank with the side nut with a socket so it's time a for a topend rebuild. I've never had to do this type of work before so a little nervous/excited. If the piston rings were bad and the engine was running hot and seized, I'm wondering what all I need for the rebuild. I see piston kits on ebay for my trike, are these okay to buy? Wiseco piston rebuild kits. Should I just buy a new cylinder with the kit? I've seen where the cylinder will come with the new pistons on ebay but I can't find it anymore (will continue looking). These are already correct size for the piston I'm assuming. But I can keep my old cylinder head? While I have everything apart, what else should I do besides adjusting the valves and timing chain tension? Thanks for the advice!

My best advice to you is to download the manual. Click the link below and download the following manual title "185/185s/200/200s (1980-1983)"

http://www.oscarmayer.net/atc/manuals/

[Pierce1989]

My best advice to you is to download the manual. Click the link below and download the following manual title "185/185s/200/200s (1980-1983)"

http://www.oscarmayer.net/atc/manuals/

I already have the manual and have read through it. It shows me how to disassemble and reassemble everything and some tips like holding timing chain with wire but it doesn't say what to do after an engine is seized. I hit something and it broke my drain plug, oil drained without knowing, then engine started seizing when hot. WOuld die then start back up again, ride for a minute, then seize again. Realized the problem, bought new drain plug and put in new oil, had it running and it was spitting white smoke everywhere so the damage has already been done. I need some advice what to do when the engine seizes and there's damage. Please help!

[yaegerb]

what I would do is take top end off and check crank small/big end play. If the play was out of tolerance I would break the rest of the motor down and get a new crank and rod. Then I would have a machine shop mic the cylinder and see if I had any bores left. If I had bores, I would bore it and get the next size piston/rings. Lastly I would mic the cam/valve guides/valves/springs to check if they are within tolerance. If not, I would replace. Also, I would get a new cam chain.

[125Mmadness]

Take the top end off and send the jug to a machine shop and see how much over boring it needs, then buy the corresponding piston. Wiseco pistons are great just don't get the 12:1 buy a timing chain and guides and you'll be good to go also the head should be fine but have the machine shop check that it's flat and also have them lap the valves.

[AMK]

When you get it apart pay close attention to the cam journals to make sure they didn't get galled.
If you didn't score the cylinder walls have someone measure them, as mentioned before, and you may get away with honing and a top end rebuild. But for certain you'll need to tear into it to see where you're at.
Now for the broken drain plug...I can't see how that would happen. Sounds like a bigger problem.

[125Mmadness]

Also measure the wrist pin journal and make sure it's not over 15mm (or whatever the size of it is)