Educate me on aluminum sleeves

[Jcary85]

So, due to some tooling failures at the machine shop, my sleeves were destroyed and the only fix was for them to custom make aluminum sleeves (nikasil coated). I’ve been told by the builder this is an excellent upgrade due to better cooling characteristics and I’ve read clearances with the pistons can be tighter due to the fact the sleeves and pistons now expand at the same rate.

Is anyone else running aluminum sleeves? Anything I need to watch out for or be cautious with?

As with all things jet ski related, I just want to do all my research.

Motor is a 10 mil 1015cc (PHP)

Thanks in advance!

-Jordan

PS - just want to clarify that I am in no way complaining about any of this. PHP is awesome to work with!! It’s pretty cool to have a unique setup like this. I just want to educate myself as I don’t think many people are running something like this.

 

[McDog]

Didnt know it was a thing.

 

[newbee]

I thought most new dirt bikes run them.

 

[vomitspot]

nickle plating is very strong ! never herd of aluminum sleeve though

 

[Storbeck]

If the idea is coming from PHP I'd have a lot of faith in doing what they say is best, but you already knew that. My main question would be why not just use a new steel sleeve? Maybe the damage was extensive enough that it actually damaged the aluminum cylinder black not just the steel sleeve?

Are you certain they are not suggesting nikasil plating the steel sleeve? I know that PHP does that. Sometimes it is a thing that is done when a cylinder has damage and it's already at it's maximum bore size.

I've heard of aluminum sleeves being used, but I've only heard of it in situations where a cylinder is being extremely heavily modified. Vintage snowmobile racing where somebody wants to/has to use the stock cylinder casting, but they are adding more or significantly changing the configuration of transfer ports so they basically bore the whole thing out and insert an aluminum piece with the new porting configuration, hard to even call it a sleeve at that point.

 

[Jcary85]

Oh I definitely trust Zack on this. Im not worried about it at all. From what I understand, it was just a timing thing on sourcing new iron sleeves. Would have taken too long and the machine shop can hand make aluminum sleeves (I assume they can’t make cast sleeves).

 

[Storbeck]

Ah that makes sense.