Dyno Results BMP Durability kit for Polaris 800 CFI's

[joey@bmp]

All Polaris Pro/Rush 800 riders that notice loss of power as time goes on. We tested the 2012 800 new and about 150hp +or- 2hp and as time and miles go on they slowly loose their grunt. The BMP Durabilty kit is engineered and tested to correct the base design flaws of the 800.


There is 2 Flaws with the 800 that are fixed with this kit. 1st flaw is high skirt load with a short skirt piston. 2nd Under case volume(not enough).


The kit corrects flaw 1 by using a taller piston and a machined shim to give the high skirt load a bigger surface area which combined with a 2 ring Wossner piston (with wide ringland) makes the entire set-up a lot more consistent as time and miles go on.


The kit corrects flaw 2 by using a .250” shim inder the cylinder to help give a more suitable case volume.


The BMP Durabilty kit maintains stock port timing and compression meaning no fuel change need to run this kit


BMP 800 CFI POLARIS DURABILITY KIT $499.95
New Release Promotion price $449.95 use code durability


Pol 800 BMP Durability kit includes:
2 - Wossner piston kits (Piston, Rings, wrist pin, Circlips
8 – Cylinder bolts
2 – Base gaskets
1 – Shim


http://bikemanperformance.com/snowmobile/polaris/rush-800/bmp-800-cfi-polaris-durability-kit.html

Sled : 2012 Polaris Pro 800
Miles : 1826
Modifications : Stock = BLACK
Modifications : Stock with BMP Durability kit = RED
Adjustable Settings : Non-Ethanol Prem
Fuel : 91 octane Non-Ethanol
Dyno : Superflow 902
Dyno Operator : Joey Strub

 

[Old Scud-doo]

Very nice. Will keep you in mind when my 13 needs a refresh after the next season.

 

[Jaynelson]

Thanks for being up front with the details.....parts list, dyno graph, price, hp figures, etc. That's really nice to see....it seems many companies want to play some guessing game on the forums these days and drip feed vague 1/2 assed info.

 

[NDFARMER95]

Looks pretty solid. Glad to see some dyno numbers. Will be something to look into down the road.

 

[d8grandpa]

A few questions on your test.
1) did you put your kit in a new sled and test against a stock sled with both sleds having 1800 miles?
2) if not did you put stock parts into a 1800 mile sled and test it with new parts to compare to a new stock sled.
Just curious if rebuilding a 1800 mile sled with stock parts would give similar results, as your rebuild kit doesn't really give any increase in power over a stock setup with no miles.
Not being critical or bashing at all just asking.

 

[sledneck_03]

I would love to see if some one is willing a stock 13 left over or new 14 to dyno the hp and then put this kit on and dyno the hp.

I heard a guy put the rk fix kit on from day one on his pro.

 

[edavis0202]

I would love to see if some one is willing a stock 13 left over or new 14 to dyno the hp and then put this kit on and dyno the hp.

I heard a guy put the rk fix kit on from day one on his pro.

I did, didn't have it for more than hr before pistons and head were changed...The Drop In Kit I should say

Worth it to me for the power and reliability

 

[joey@bmp]

A few questions on your test.
1) did you put your kit in a new sled and test against a stock sled with both sleds having 1800 miles?
2) if not did you put stock parts into a 1800 mile sled and test it with new parts to compare to a new stock sled.
Just curious if rebuilding a 1800 mile sled with stock parts would give similar results, as your rebuild kit doesn't really give any increase in power over a stock setup with no miles.
Not being critical or bashing at all just asking.

Good Question, a new motor would typically make around 150-152 HP so there is a slight increase in power due to corrected case volume.

 

[AndrettiDog]

My understanding of the timing is vague, but doesn't the shim effect the timing and thus require a timing key?

 

[Leftys]

Ignition timing is not affected by shimming the cylinder. It is port timing that will be affected, but they install a taller piston to keep the port timing the same as stock.

 

[joey@bmp]

My understanding of the timing is vague, but doesn't the shim effect the timing and thus require a timing key?

There is absolutely no change in port timing or ignition timing due to the installation of this kit. So no adjustment is needed.

 

[Teth-Air]

Doesn't raising the piston and increasing the case volume also lower the charge pressure from the case to the top of the cylinder? I would have expected this then to negatively impact performance? My basic thinking is if you squish the air in the case to half it's original size the pressure would double but if you only squish it 75% of its original size, the pressure would only increase 1.5 times. Obviously I am missing something here as the dyno sheet suggests but I would like to understand the gains in HP.

 

[joey@bmp]

Doesn't raising the piston and increasing the case volume also lower the charge pressure from the case to the top of the cylinder? I would have expected this then to negatively impact performance? My basic thinking is if you squish the air in the case to half it's original size the pressure would double but if you only squish it 75% of its original size, the pressure would only increase 1.5 times. Obviously I am missing something here as the dyno sheet suggests but I would like to understand the gains in HP.

You understand how the case pressure works better than the average person, If you were pumping a liquid less case volume would pump more to top of piston hands down. Now to add to your knowledge less case volume will not always push more air to the top of the piston. Since air has mass it therefore has inertia. Since the inertia can help trap more air past the reeds it is possible to trap more air than the case would hold at atmospheric pressure. This makes the engine have a fine balance between under and over case volume. The 800 CFI is from the Factory has insufficient case volume.

 

[beamslayer]

So in reality this is the same as the mtntek kit other than the pistons are not wiescos ? I run the Mtntek kit and am very pleased with the response of the engine . I believe North Star kit is also along similar lines except they use a timing key .
I am glad to see more options for the 800 poo engine . Eventually we will end up with a reliably engine that produce equal hp to the other brands .

 

[milo303]

Sent you a pm joey

 

[milo303]

So in reality this is the same as the mtntek kit other than the pistons are not wiescos ? I run the Mtntek kit and am very pleased with the response of the engine . I believe North Star kit is also along similar lines except they use a timing key .
I am glad to see more options for the 800 poo engine . Eventually we will end up with a reliably engine that produce equal hp to the other brands .

You watch, the pro will have a totally new motor next year ( =

 

[beamslayer]

Are they going the same route as cat and running Yamaha engines ?

 

[TheBCSledder]

Are they going the same route as cat and running Yamaha engines ?

I sure hope not

 

[nulty_23]

Will this kit still work with your bolt on performer kit

 

[m1kflyingtiger]

Any chance you have dyno numbers of a sled with your durability kit after 1800 miles of use? It just seems to me that if the top end needs freshening up you would have similar results regardless of if it was a dragon saver, fix kit, drop in kit, new aftermarket pistons and rings, or even new stock pistons and rings.