FYI..NEW Product Announcement. Polaris 800 Direct Replacement Pistons

[Einar74]

Angermanagement890.

this is a info from RKT website. the link is at the bottom

There is no RPM change with this kit. The kit simply addresses the issues associated with the stock (OEM) Piston.

We will be offering this kit throughout the Summer and the following seasons.

Piston side loading is reduced due to our unique piston's weight. Yes, this piston is much lighter than the OEM piston and having a lighter piston will reduce piston side load pressures AND reduce the stress on the crank!

Less Stress = More longevity and more power!

We, REALLY, do address the OEM piston design issues with this kit.

No more "SLOPPY" OEM piston with poor piston geometry.

BEST PART: NO AFTERMARKET PIPE, Fuel controller, OR anything else is needed! We, purposely, designed this kit to perform using the components!

Once you have the kit installed.. YOU ARE DONE!!

Reliability is NOT compromised in any way, shape, or form and the cost is VERY affordable.

http://www.2strokeheads.com/Polarispistons.htm

 

[beamslayer]

Thanks to both of you for coming up with alternatives.
Now back to the topic at hand. Would you suggest for those of us that are considering the drop in kits to have are cylinders striped and renikisil to check for cracks? Also do you provide that service?

 

[RKT]

Thanks to both of you for coming up with alternatives.
Now back to the topic at hand. Would you suggest for those of us that are considering the drop in kits to have are cylinders striped and renikisil to check for cracks? Also do you provide that service?

Good question

Here are my thoughts.. When the cylinder is stripped and visually inspected for problems/cracks, this is justa visual inspection..

There could still be cracks and the only way to really tell if the cylinder is developing a crack is to have it magna-fluxed.

We do not offer the magna-flux service..Really not sure who does..

So, I guess what I am trying to say is that without a magna-flux test, there is no way to be certain that there are not cracks..

Kelsey

 

[Norway]

Good question

Here are my thoughts.. When the cylinder is stripped and visually inspected for problems/cracks, this is justa visual inspection..

There could still be cracks and the only way to really tell if the cylinder is developing a crack is to have it magna-fluxed.

We do not offer the magna-flux service..Really not sure who does..

So, I guess what I am tryingt to say is that without a magna-flux test, there is no way to be certain that there are not cracks..

Kelsey

Tip: A serious mechanical shop should be able to magnaflux-test your cylinder. At least those that do welding.

Engine-overhaul shops, doing oversized bearings for 4-stroke cranks, should also use something to show possible cracks before they machine it.

RS

 

[beamslayer]

I checked on magnafluxing process for the cylinders. Aluminum is not magnetic so they can not be magnafluxed. They said they would have to be pressure tested either by vacuum or pressure. Next step would be a plating company I guess?

 

[rocket]

Correct, no "magnaflux" or similar test possible for aluminum. Only a dye-penetrant test is useable. The problem there is that the castings themselves have porosity (which is normal), which will make results more "murky" to interpret. Vacuum/pressure testing isn't going to be useful either because the problem is the cylinder skirts, not leaky water jackets. Figuring out whether used cylinders are damaged or not will be a tough thing to do.

 

[indydan]

Dragon/Pro Cylinder Sleeves

Yes its impossible to accurately check a cylinder for cracks.

Thats why I do this to every cylinder that goes on the 3 & 5 year warranty motors.

Attached is 1 photo of a Stock Polaris Cylinder.

The next 5 photos are what the completed cylinder looks like after they are completed.

Dan

 

[TRS]

Are you offering 3 piston sizes?
Polaris has A, AB, and B cylinders.

 

[GREICO1]

That would be new. There are 2 different cranks, but the parts fiche only indicates 1 piston kit for the 800 motors.

 

[indydan]

Are you offering 3 piston sizes?
Polaris has A, AB, and B cylinders.

I use the same Piston in all the Small Block 800 Motors. All cylinders are replated and then they are custom fit to a fresh set of pistons.


Polaris has worked on piston change but they superseed to the last piston built.

 

[TRS]

Dan, I understand your process. I was wondering about Kelsey's kit????

Greico1, each cylinder is marked with the letter A,AB,or B. But you are correct Polaris only offers an AB piston kit. If you look on the piston kit box you will notice it has an AB marking.

A rod ratio of 1.8857142 is unacceptable.

 

[Super Dave3]

A couple of questions for Dan and Kelsey. Dan will you offer the cyl skirt mod repair, and at what cost? Kelsey will your lightweight piston work well in boosted engines?

 

[RKT]

A couple of questions for Dan and Kelsey. Dan will you offer the cyl skirt mod repair, and at what cost? Kelsey will your lightweight piston work well in boosted engines?

Yes, the plate houses weld the skirts quite often and do a great job with it.. So, a broken skirt is not a junk cylinder (usually)

As for a turbo... yes,I see no reason why thepiston would not work great. We have one guy in Canada running the drop in kit with a turbo.

TRS.. curious... what is an acceptable rod ratio? Again, Polaris has the best 800 rod ratio on the market... Honestly, curious as to what you would like to see for a rod/ratio?


Kelsey

 

[TurboMatt]

A couple of questions for Dan and Kelsey. Dan will you offer the cyl skirt mod repair, and at what cost?

Dan, I'm wondering this same thing? Could a person just get the beefed up cyl skirts done from you and would they work with the stock configuration

 

[beamslayer]

Being this is RKT post I doubt Dan will answer. I pm Dan this morning with the same ?? since I am thinking about going with the 858 kit a little extra support should not hurt anything.
My other ? is will it change case fill or change the way the air flows under compression and what Kelsey thinks about adding this to his kit?

 

[indydan]

A couple of questions for Dan and Kelsey. Dan will you offer the cyl skirt mod repair, and at what cost? Kelsey will your lightweight piston work well in boosted engines?

Yes I will answer, I will do the cylinder work to anyones cylinder to run anyones piston I do not care what piston you run as long as I do not have to warranty it.

Broken sleeves do not matter and I do not need the busted piece.

I just need finish bore size, And the Finsihed Price is $795.00 ready to install. Pistons Not included. No warranty.

If I supply the Pistons its $995.00 complete with a matched set of Piston & Top-end Gasket set.

Dan

 

[indydan]

Being this is RKT post I doubt Dan will answer. I pm Dan this morning with the same ?? since I am thinking about going with the 858 kit a little extra support should not hurt anything.
My other ? is will it change case fill or change the way the air flows under compression and what Kelsey thinks about adding this to his kit?

I have been doing this cylinder mod for awhile & and I have a good amount of them out there and most people donot know they have this cylinder Mod because at first i didn't charge for it because I wanted unbiased feed back. No one has mentioned any change in performance other then they say they run awesome and that is simply because the motors are now in tolerance, no other reason.

Dan

 

[indydan]

Dan, I'm wondering this same thing? Could a person just get the beefed up cyl skirts done from you and would they work with the stock configuration

OPPS!! Sorry i missed you.

Most of the cylinders I have done are on all stock configuration motors.

It works flawlessly & longevity is greatly increased.

 

[TRS]

Kelsey, with a 70mm stroke and a 85mm bore it should be north of 1.92. A smaller bore can use a lower rod ratio.
We all have opinions on this issue. I base my findings on, in the field, engine failures.
Remember, we are not talking max HP here, we are talking a compromise between HP/longevity. The 800 needs major help in the longevity department.

 

[jsandgren10]

Yes I will answer, I will do the cylinder work to anyones cylinder to run anyones piston I do not care what piston you run as long as I do not have to warranty it.

Broken sleeves do not matter and I do not need the busted piece.

I just need finish bore size, And the Finsihed Price is $795.00 ready to install. Pistons Not included. No warranty.

If I supply the Pistons its $995.00 complete with a matched set of Piston & Top-end Gasket set.

Dan

So does this mod really help with breaking skirts? If you supply pistons and all as a matched set is there any warranty? If so is it only stock motors or Turbos also? Thanks.