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Auto_Demon
03-15-2011, 03:54 PM
Soon i will be rebuilding my 83r and my friend told me that i cant just put in a new piston and rings and go, he said that i need to re-sleeve it in order for it to run good. is this true? what else do i need to do?

ktmbk
03-15-2011, 05:01 PM
I would need to know more to give an answer. It depends on the cylinder's condition and how much damage is in there, and what the cylinder is board to now.

I've gone through many over boars and two sleeves on one of my 250r engines.
If the top end self destructed usually it means an over boar and new piston minimum. If there was no cylinder damage sometimes you can get away with a new piston and rings, though a hone is usually a good idea, and a boar and oversized piston may still be needed if the cylinder is worn. The largest piston I use to find was at 80 over (excluding big boar kits), and they come in 10 over intervals. From the way you describe it there was damage.
To find out what you need to do, you need to measure your current boar, estimate how much damage is done to the cylinder walls and try to figure how much material would need to be removed get a clean surface, then see what size piston you would need to get in that range. Don't assume you can just go one size up, and don't go larger than you would need to. Most places that would boar your cylinder that are worth anything will require you to have a piston on hand so they can match any clearances. It's best to get the measurements done by the person who will be doing the work on the cylinder to avoid buying the wrong sized piston and then having to return or exchange it.
If you do need to sleeve it will cost more but it will also return your engine to a stock boar size, and if done correct stock reliability. If you do have to go this route be sure to have a shop with experience with these engines do the work as it will require pressing in a new cylinder and matching the ports in it to the engine.

HONDA_ATC_FREAK
03-15-2011, 05:22 PM
no you don't have to re-sleeve for it to run good, good lord think of all the money you'd waste if everytime you needed to rebuild you went out and bought a new sleeve. You bore it out to the next size then get the correct piston kit for it and your good to go. Sometimes if it's not bad you can get away with honing the cylinder and then new rings but this is not usually what happens.

Auto_Demon
03-17-2011, 10:46 AM
I would need to know more to give an answer. It depends on the cylinder's condition and how much damage is in there, and what the cylinder is board to now.

I've gone through many over boars and two sleeves on one of my 250r engines.
If the top end self destructed usually it means an over boar and new piston minimum. If there was no cylinder damage sometimes you can get away with a new piston and rings, though a hone is usually a good idea, and a boar and oversized piston may still be needed if the cylinder is worn. The largest piston I use to find was at 80 over (excluding big boar kits), and they come in 10 over intervals. From the way you describe it there was damage.
To find out what you need to do, you need to measure your current boar, estimate how much damage is done to the cylinder walls and try to figure how much material would need to be removed get a clean surface, then see what size piston you would need to get in that range. Don't assume you can just go one size up, and don't go larger than you would need to. Most places that would boar your cylinder that are worth anything will require you to have a piston on hand so they can match any clearances. It's best to get the measurements done by the person who will be doing the work on the cylinder to avoid buying the wrong sized piston and then having to return or exchange it.
If you do need to sleeve it will cost more but it will also return your engine to a stock boar size, and if done correct stock reliability. If you do have to go this route be sure to have a shop with experience with these engines do the work as it will require pressing in a new cylinder and matching the ports in it to the engine.

it is the stock bore andi dont know the condition oif the cylinder

younganreckless
03-17-2011, 09:55 PM
Ya if it's on fist bore u will deft not have to resleeve