Need Used 800 CFI single ring pistons

[EricW]

Anybody out there have a set/single of Polaris 800 CFI single ring pistons. Maybe one that scuffed or you pulled when you did the update kit. I could really use one for some measurement stuff I'm working on and comparison to the dual ring pistons. It has to be the single ring style that came OEM on the 08-09 models. I would be glad to pay for shipping or a beer if I come to your place. I would even be glad to trade for anything in my rubbermaid tubs of crap that you might need. Any help is appreciated. Shoot me a pm or email.

Thanks. EW

EricW@centurytel.net

 

[thefullmonte]

Sent you an email.

 

[INDEEP]

How bout 1/2 of a 2 ring piston for one bottle of Kokanee?

 

[EricW]

How bout 1/2 of a 2 ring piston for one bottle of Kokanee?

If its the left half I'll go a Kokanee light. lol.

 

[polhiker]

i have 2 brand new ones

 

[EricW]

i have 2 brand new ones

Thanks for the response, I was looking for ones that scuffed or had skirt issues, but not wasted beyond being mic'd from all dimensions. Have a good one. EW

 

[03RMK800]

Eric,
I am very interested in the dimensions you come up with. I am trying to determine what diameters of pistons and cylinders were "in spec" according to Polaris. I also am trying to figure out if the two ring update pistons were different from the one-ring piston diameters.

Would you share what you find?
Are you measuring cylinders, too?


Of course, there's a reason-- I am working on a theory that Polaris made the CFI 800 pistons too small, because I am mad about being on the sled's third top end in 900 miles.

I will send you what I come up with.
Thanks!
03rmk800
Alan

 

[SpokaneRMK]

Eric,
I am very interested in the dimensions you come up with. I am trying to determine what diameters of pistons and cylinders were "in spec" according to Polaris. I also am trying to figure out if the two ring update pistons were different from the one-ring piston diameters.

Would you share what you find?
Are you measuring cylinders, too?


Of course, there's a reason-- I am working on a theory that Polaris made the CFI 800 pistons too small, because I am mad about being on the sled's third top end in 900 miles.

I will send you what I come up with.
Thanks!
03rmk800
Alan

Just lost my top end also, pistons measured 84.44mm with the cylindar reading 84.99, so i'd say they are outta tolerance(alot).

 

[thefullmonte]

Polaris specifies that you measure the pistons 10mm up from the bottom. There is a very small area that you will find the pistons to be the widest. They certainly aren't a straight up and down piston. They are smaller at the top and bottom. Reguardless, they usually are out of spec before they are even installed.
I will be curious what Eric comes up with as well.

 

[03RMK800]

Weeks later, here is what I found:

The pistons were different-- one was 3.320 in (84.328) and the other 3.338
(84.7852). The clearances were .027 (.6858) and .009 (.2286) -- neither within spec.

Its not all pistons-- the factory new cylinder bore installed 389 miles ago measured 3.347 inches, or 85.01 mm. That is large enough that a full diameter piston (85 mm or 3.34 inches, would have been close to factory clearance.

It was fun-- I could get a .035 in/.88 mm feeler gauge between the skirt and the cylinder with the piston at top of bore. The little piston practically drops in without trying to compress the rings-- gravity will do it.

I now have Wiseco pistons in a re-nick-ed cylinder block. Even with dealer labor, saved nearly $600 over Polaris factory new parts.