Cylinder Work

CarlinoJoeVideo
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2/19/2018 6:09am
Hey guys, my 125 is on it’s way to 80+ hours. When I rebuild the whole thing, should I have the cylinder redone(replated). If so, who do you recommend? Anyone in Southern Cal?

Thanks!
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Tuna
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2/19/2018 6:17am
Replate if it needs a replate. If not wait until it needs one.
CarlinoJoeVideo
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2/19/2018 6:20am
Tuna wrote:
Replate if it needs a replate. If not wait until it needs one.
And that’s just a measurement thing?

Do you guys recommend crank rebuild and balance or buy all new crank?
jeffro667
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2/19/2018 6:28am
Tuna wrote:
Replate if it needs a replate. If not wait until it needs one.
And that’s just a measurement thing?

Do you guys recommend crank rebuild and balance or buy all new crank?
If you're in spec, don't bother with the re-plate. As far as the crank, I would have it rebuilt if needed, many crank rebuilders get them better than they come from the factory.
mxdevon
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2/19/2018 6:41am
In so cal......125 2smoke....... you could walk in to PC! I think I'd do that if I we're that close.
Replating the cylinder is a decision you would make after inspection once you tear down. Good chance it's not necessary. The wrench rabbit kits do seem very complete and a good value for a full rebuild.

The Shop

KooyaKooya
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2/19/2018 8:25am Edited Date/Time 2/19/2018 8:26am
Tuna wrote:
Replate if it needs a replate. If not wait until it needs one.
And that’s just a measurement thing?

Do you guys recommend crank rebuild and balance or buy all new crank?
In my experience, it's not a measurement thing but more about visual inspection. The nikasil will usually become visually damaged well before it wears out from excessive hours on the engine. So while you could measure the bore and compare it to spec, determining nikasil health that way, it's often not necessary if the plating looks healthy, without any chipping or vertical streaks and still with good crosshatch. If it looks healthy, then the bore is likely to be in spec. Any imperfection you can feel with your fingernail is definitely cause for a replate. Also check for ring ridge at the top of the bore.
CarlinoJoeVideo
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2/19/2018 8:32am
Tuna wrote:
Replate if it needs a replate. If not wait until it needs one.
And that’s just a measurement thing?

Do you guys recommend crank rebuild and balance or buy all new crank?
KooyaKooya wrote:
In my experience, it's not a measurement thing but more about visual inspection. The nikasil will usually become visually damaged well before it wears out from...
In my experience, it's not a measurement thing but more about visual inspection. The nikasil will usually become visually damaged well before it wears out from excessive hours on the engine. So while you could measure the bore and compare it to spec, determining nikasil health that way, it's often not necessary if the plating looks healthy, without any chipping or vertical streaks and still with good crosshatch. If it looks healthy, then the bore is likely to be in spec. Any imperfection you can feel with your fingernail is definitely cause for a replate. Also check for ring ridge at the top of the bore.
Ok very interesting! I’ll post some photos when I put the next piston in. Appreciate the info guys!
BobPA
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2/19/2018 8:45am
If you did not suck any dirt or have any type of piston/crank failure, the cylinder should be fine. I would have Crankworks rebuild your OEM crank. The wrench rabbit kits come with a Chinese crank...something I would never trust in my bike....especially in a small bore.
2/19/2018 9:40am
You can hit the plating with some scotchbrite to get rid of any glazing and get some crosshatch back if it’s there.

Don’t hone it.

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