New cylinder liner

[DGardner]

I have a Super combat engine that I pulled apart and found that the liner at the bottom was cracked. So is there a place that can put a new sleeve in the cylinder? Thanks DG

[dirtsquirt80]

I know Harlin Diem has done them before

[Dale]

Doug,
You might look over this site and maybe call and discuss it with them. They do some amazing things. Just one option... albeit not a cheap one.
Dale
http://www.powersealusa.com/repair-process/

[bchappy]

Years ago I had one from a customer that had let it get too much wear and the banging around of the piston split it at the bottom. It needed boring anyway so I welded it on the outside just for support and ground it back smooth and when bored it must have worked as it never came back. That is just an option. I think Power Seal could do a similar repair. Give them a call. They won't be cheap but they do good work and Super Combat cylinders are a little hard to find. If you decide to throw it away I will give you my address.

[racerclam]

Not a huge problem , I have and can tig weld it with silicon bronze rod and rebore to make round again . Call me if you want 702-858-9177

Rich

[DGardner]

I never thought about welding it! Thanks DG

[Zyx]

I would take up the offer to TIG and rebore, which PowerSeal would have to do anyway, in order to apply their process, or they would have to overbore it, sleeve it, rebore it, and then seal with with Nikaseal (or Nikasil depending on who offers the product and service). I believe PowerSealUSA would just weld it up and proceed, but you would have to ask them. PowerSealUSA does a bit of vintage bike processing, and comes recommended by many, but with a cracked skirt, that crack has to be repaired first regardless of which way you want to go.

PowerSealUSA lists prices on the site for what they will do, and for you it looks to me as if they would charge around $234 to strip, weld, bore, plate, and hone. The difference between doing it with TIG and rebore, or using NikaSeal, is that with the first process, you are back in the game with what you had before (assuming you are not already bored out to the max), but likely one bore size higher than before; with the second you are back in the game ahead of where you started, as the NikaSeal process creates a cylinder surface that is just about impossible to wear out, and I believe is a little easier on rings and pistons. Another point to consider is that with NikaSeal, if the original bore is not grossly worn, they may be able to plate and hone back to the original dimension. Read about their process on their website.

So you have options, and are at a place where you can make a really interesting choice. Your cylinder is repairable readily by a pro, who has already offered his services and is an excellent way to go, or if you want to go the high zoot route, you can have it done by PowerSealUSA, and then you can casually drop comments like," Oh yeah, I had it NikaSealed." Some of the folks who have gone that route can comment on whether it improves performance. Potentially, it does from a coefficient of friction point of view. Whether the PowerSeal prices are expensive is also a point of view. Certainly they are higher than just having the skirt repaired, but since we are talking about a vintage MX bike with lots of potential and lots of retained value, $300 is not that much.

[Darrell]

I didn't think an "Alumaferric Cylinder" could be re-sleeved. Can somebody clear that one up either way?

Happy Hodakin,

Darrell

[Zyx]

Not "re-sleeved" because the original process is a bi-metal casting of some sort not a sleeve. But if the ferric part is bored out, the aluminum casting can be sleeved -- as far as I know having never done it. If someone has tried it, let us know how it worked.

[DGardner]

Thanks for all the help!