Opposing Top-end Overhaul Suggestions...

[europe50]

Hello, I have a 2015 Polaris Axys Switchback 800 with about 4500 miles on it, and would like to do a top end.

I have read many articles on a couple competitive processes, but have not seen a clear consensus.

There are two leading methods that I have read in doing a top end on these 800's...

One process, is to purchase RK-Tek pistons, have the cylinder diamond honed for a medium finish in order to get the rings to wear in properly. Check ring gap and reassemble.

The secong process, is to purchase OEM Pistons, send the cylinder for the HG7 finish honing from Indy Specialties for the smoother finish since the rings are so well built now, they don't need the wear. Check ring gap and reassemble.

These these are two opposing mindsets on how to how to handle honing a cylinder and which pistons to use.

Both companies have a great reputation, but I would like to try to form a consensus from experienced members on which process they believe provide the best results, and more importantly, why?

Thank you guys!

 

[IcutMetl]

I’m not a Polaris rider and both those guys know way more than me, but I will cast my vote for Indy Dan. I purchased some RK Tek domes for another sled of mine, and the quality of machining on them was bush league. That left a sour taste in my mouth.

 

[GoBigParts]

I trust the OEM with the HG7 hone and that would be my number one choice for top longevity. To be honest eithrer one wil be better than the ones in there with that kind of miles. The key is to keep an eye on your performance and compression. When ever I would loose a little RPM or performance I would have dealer check compression and they did end up replaceing my top end for me on my 2012 a couple times under warranty. I could just tell. Mine was just rebuilt with stock parts and always ran fine. I feel my 800HO Axys motors have been better. But I haven't ridden one as many miles as I did my 2012. I have even used aftermarket SPI sotck like pistons and have had good luck.

 

[North Dakota 322]

Call up indy dan and talk to him in person, his advice for my 2000mi 800 was to just run oem pistons and don't touch the cylinder at all.
Great guy to talk to.

 

[gtwitch]

Ditto on getting ahold of Indy Dan. He will not steer you down a wrong path. I have done the plateau hone and stock pistons more than once and never been disappointed or let down on performance and longevity.
gtwitch in wyoming

 

[chevy_man]

I've never honed a nika-sil cylinder. Had some that went through 4-5 sets of pistons and never had an issue seating rings. Melted/stuck a piston in one, and after a muriatic acid bath to remove the melted aluminum off the nika-sil it got a new piston and rings and is still running today.


I have done some interesting things to older cylinders to get them going again. Steel sleeves from a commercial diesel application into bored out cylinders with a press fit, pistons from all different manufacturers to get stuff to fit when bore sizes got changed, etc.


End of the day, change your rings before they cause chipping in the exhaust ports. Don't hone a cylinder, get it plated and honed or leave it alone. If there's no damage, no need for new plating.

 

[Clarke673]

chevy man i agree to an extent. I once wrote a long post in great detail about this and honest;y just don't have time to do it right now. Powermods on youtube does a decent job. End of the day, "take it to indy dan" is lingo for you don't trust yourself with a more or less simple task. SEE. The reason i learned anything in life was because i couldn't afford to have others do things for me. With respect due to all parties and a big list of exceptions... Theoretically you get what you give an engine. I mean, indy dan. Kelsy. Whomever is NOT going to be willing to spend the amount of time building YOUR engine that you can. It really doesn't require much more than basic tools to measure ring end gaps. torque fasteners, or install "free performance" ontop of your rebuild for "free*".

I measure every piston, rod, and wrist pin for a product check. then grind in spots to make a "blueprinted motor". Which, is NOT the same as having one come out balanced spinning 8500. There truly is a lot of room for black art in engine builds and thats true for sleds to diesel trucks. Im sure its frowned upon in the aviation business but id bet $1 those a-holes have more steps than anyone to acheve the same thing. And that is an engine with a lifespan that will NOT EVER last forever.

I say do as much as you can yourself