Need Bored??

[mike84bigred]

Pulled apart my 200s cylinder. It was seized when I got it and while inspecting the cylinder, I noticed the oil ring may have done some damage to the cylinder wall. You can feel it a little when you run your finger over it. Should this be re-bored, or you guys think it would be ok with new rings?

[barnett468]

Hello mike84bigred


Some people here might tell you to run it as is or hone it and run it. Your rings will never properly seal, guaranteed, and will premature wear. You can also check for taper and "roundness. If it is out by either by around .002 it is best to rebore. Keep in mind that if it is out both ways by .002 that adds up to .004. I personally would do it right the first time so at least that part will be good for at least another 10 years or more [providing you don't get any sand in it].

[mike84bigred]

What would be good you think? .030 overbore? Now correct me if i'm wrong, boring .030 would require a 65.75mm piston?

[El Camexican]

What Barnett said. Nice tight snug fitting holes are highly underrated :naughty:

[barnett468]

What would be good you think? .030 overbore? Now correct me if i'm wrong, boring .030 would require a 65.75mm piston?

Hello

If it was me I would take it to a good bore shop, have them rough bore it until it almost or just barely cleans and have them tell you what size piston you need then buy it and give it to them once you get it. A good shop will know what to do.

[250r'en +TCB]

If it wasn't that bad I would just bore it .010 over, that way you only have to get new rings from wiseco and not a new piston and rings like when boring .030 over. But again it's a judgement call depending on how bad the cylinder is.

[mike84bigred]

Hello

If it was me I would take it to a good bore shop, have them rough bore it until it almost or just barely cleans and have them tell you what size piston you need then buy it and give it to them once you get it. A good shop will know what to do.
Give it to them? Lol. I've done this many times before, not the boring part, but definitely the assembly. What's the max you guys think I should go? Don't want to have to change the jets or anything like that.

[barnett468]

Give it to them? Lol. I've done this many times before, not the boring part, but definitely the assembly. What's the max you guys think I should go? Don't want to have to change the jets or anything like that.

Hello mike64bigred

Sorry but I don't understand your question. I've had over a hundred cylinders bored doing exactly what I said, what could possibly be the problem with that? You have to give it to them to get it bored even if you have the piston. If you want to know the farthest you can bore it and still not overheat that's a different question. As far as not wanting to change jets, that makes no sense to me. Are you saying that if you have to install a 1 size larger main jet if it gets bored out you are not going to bore it out? Seems like it's a lot easier to change a jet than it is to rebuild a top end.

[El Camexican]

Give it to them? Lol. I've done this many times before, not the boring part, but definitely the assembly. What's the max you guys think I should go? Don't want to have to change the jets or anything like that.

No one on here can "guess" how much you need to bore your cylinder. For all we know its at it max. already. Take it to someone with the proper tools to measure it and determine what the minimum amount to clean it up is required and then find out what sizes of pistons are available, buy it as well as the rings and wrist pin. Take them to to the machine shop and have them bore and hone to match the piston, gap the rings and you are done. FYI: If your jetting was correct before this and you bore .010", .020", or even .030" it is unlikley you will have to rejet for such a mild engine.

[mike84bigred]

I see what you mean about taking the piston to the shop. Forgive me for not understanding your post entirely. I'm tring to read from a memorial day picnic and the sun is in my face. My question was not very complicated though. I have to bore it out so the pits are gone. As far as I can tell, iys a standard 65mm. Just want to tell the shop if its anything over .030 or. 040, don't bother.

[El Camexican]

I see what you mean about taking the piston to the shop. Forgive me for not understanding your post entirely. I'm tring to read from a memorial day picnic and the sun is in my face. My question was not very complicated though. I have to bore it out so the pits are gone. As far as I can tell, iys a standard 65mm. Just want to tell the shop if its anything over .030 or. 040, don't bother.

If you have a stock bore it will likley clean up with .020", but do take it to a pro before you buy any parts.

[mike84bigred]

I'm weighing my options right now. To get it bored, and new piston, plus everything else I would need, I seem to be going over budget of what I want to but into this thing. I bought it for goofing around the yard and also for yard work, I just don't want it to smoke. Decisions, decisions

[just ben]

Take the cylinder over to Motion craft in East Aurora. Great shop,they can get you fixed up in no time.

[mike84bigred]

I sent motion craft an email. We'll see what they say.