My RKT 858 experience
- Thread starter IQRIDR
- Start date
This has been some of the most interesting reading I have seen lately.
There is a fellow 11 pro owner close to me and we are disscussing which drop in kit to go with he is going with RKT kit and I am looking at the fix only because I already have the PA head and Hps can.
We ride in the same area so it should be a good test and I have never met him only talked to him on the phone.
Is there any one with a dyno in N Idaho or N E washington ??
I truly wanted a BB but $$$ talks and I have other plans for my Assault like a 163 track and of course I need to address the folding tunnel issue
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I hope to start removing the engine this week and checking on the wear of the p/c hopefully Tom will share his info also on his build.
There is a fellow 11 pro owner close to me and we are disscussing which drop in kit to go with he is going with RKT kit and I am looking at the fix only because I already have the PA head and Hps can.
We ride in the same area so it should be a good test and I have never met him only talked to him on the phone.
Is there any one with a dyno in N Idaho or N E washington ??
I truly wanted a BB but $$$ talks and I have other plans for my Assault like a 163 track and of course I need to address the folding tunnel issue
.I hope to start removing the engine this week and checking on the wear of the p/c hopefully Tom will share his info also on his build.
I'd pay for the Cliff Notes version of this thread (and maybe the Long Rod Pro Motor one too)!
Cliffnotes:
IQ posted his experience with the 858 kit. He made sure to point out he liked the sled, but he had issues with the sled-mainly scoring on the cylinders and the rods and scoring.
AKsnow has been asking a bazillion questions about the kits and the engine dynamics and such- seems to be looking for information about kits in general.
RKT came on here at first mentioning how its the internet and how things blow up fast and for no reason and got defensive(which I would too if my reputation and livelihood were being bashed no blame there) He mentioned how without seeing the parts he cannot conclude what went wrong and that the kits he has put out thus far have been successful and have a good track record thus far. Then proceeded to answer a bazillion questions from AKsnow.
IQ posted his experience with the 858 kit. He made sure to point out he liked the sled, but he had issues with the sled-mainly scoring on the cylinders and the rods and scoring.
AKsnow has been asking a bazillion questions about the kits and the engine dynamics and such- seems to be looking for information about kits in general.
RKT came on here at first mentioning how its the internet and how things blow up fast and for no reason and got defensive(which I would too if my reputation and livelihood were being bashed no blame there) He mentioned how without seeing the parts he cannot conclude what went wrong and that the kits he has put out thus far have been successful and have a good track record thus far. Then proceeded to answer a bazillion questions from AKsnow.
Honest question here.
Was the kit in question a proto, test, or otherwise not part of production kit?
If so, why does this thread exist?
My understanding is that it was a test setup, but perhaps that was incorrect.
I've tested products in the past & usually very specifically part of that deal is that you can NOT disclose info & that you don't talk to anyone other than the builder/ product producer about it until after he/ she gives the OK. One such conversation I had was with Kelsey, where I was a dufus & mentioned a good thing about his head that he had done, and he simply asked me to pull it... easy fix. Maybe I'm misunderstanding the nature of the relationship?
Was the kit in question a proto, test, or otherwise not part of production kit?
If so, why does this thread exist?
My understanding is that it was a test setup, but perhaps that was incorrect.
I've tested products in the past & usually very specifically part of that deal is that you can NOT disclose info & that you don't talk to anyone other than the builder/ product producer about it until after he/ she gives the OK. One such conversation I had was with Kelsey, where I was a dufus & mentioned a good thing about his head that he had done, and he simply asked me to pull it... easy fix. Maybe I'm misunderstanding the nature of the relationship?
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X2Freeride
Well-known member
Lets look at this from a manufacturing stand point.
If something can be improved upon to any degree then they current system in placed is flawed. Until you get to a "Poka-Yoke" condition the current condition is NEVER ideal. Since we have facts that prove that these engines have a side loading issue to a degree, and their are documented failures, we can surmise that even if only half of the failures are directly related to a side loading issue then there is still a substantial problem. Even before getting any real data to back up these claims.
The basic principle of manufacturing when your making a new product is to take the current product already in place study it, document its weak points address them (at least the worst ones) and try improve upon or eliminate them if at all possible.
When your going to a big bore version of an engine that already has known side loading issues it becomes even more critical to the longevity of your product that you address all of the known issues to ensure the longevity of your product.
Its very hard to address every single issue with a given product especially when your also changing the condition of the product in addition to making these improvements. IE larger bore size, however as I stated earlier from a longevity and reliability standpoint this is CRITICAL to the success of your product that address as many of these issues as possible.
Cost is always a factor in the quality of a product, just as you stated and their is a fine line between failure rate and the cost of improvements to lower that failure rate. In business though your only as good as your weakest product. In order to differentiate your product from theirs and get ahead of the curve is to do the things they wont do and a build a product that is more reliable then theirs.
BCIL, my understanding(going off the thread kelsey anounced the 858 kit in) is this was a ready to go consumer kit that he wanted to give to someone at reduced price that lived at low elevation for low elevation testing..but maybe chad(IQRDR) or kelsey can expound on the agreement...
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pura vida
Well-known member
that was my understanding of the situation also. just some low elevation map refinement before released to the public. and if you look back, chad had posted his initial impression which were very positive. i'm guessing he felt it was necessary to follow up and post what the latest was. it wasn't presented as a bash thread. as i see it, the only "mistake" chad may have made was to post his initial impressions too quickly. if that wouldn't have been done then this thread wouldn't have been necessary. but i, along with the vast majority of others, would have done the exact same thing in a similar situation. so take it for what it is.
pv
pv
K
knifedge
Well-known member
--Quote--
When your going to a big bore version of an engine that already has known side loading issues it becomes even more critical to the longevity of your product that you address all of the known issues to ensure the longevity of your product.
-- Cat 800 has same bore x stroke as Polaris CFI2. Cat BB is substantially larger at 925cc compared to Polaris BB 858. So, what side loading issues are you talking about?
--It is not about "side loading" as much as it is about actual piston design and engine lubrication. RKT seems to address the piston design issue and the CFI2 owner/rider needs to address the lubrication issue.
When your going to a big bore version of an engine that already has known side loading issues it becomes even more critical to the longevity of your product that you address all of the known issues to ensure the longevity of your product.
-- Cat 800 has same bore x stroke as Polaris CFI2. Cat BB is substantially larger at 925cc compared to Polaris BB 858. So, what side loading issues are you talking about?
--It is not about "side loading" as much as it is about actual piston design and engine lubrication. RKT seems to address the piston design issue and the CFI2 owner/rider needs to address the lubrication issue.
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X2Freeride
Well-known member
Cat addresses the side loading issue through piston and cylinder design. There is a reason why Cat's piston skirts are 37% thicker than Polaris's are. Their cylinders are also of a much better design. They also address the issue with dissipating heat from around the bore that Polaris does not.
K
knifedge
Well-known member
-- Cat places wrist pin location at optimum position. I believe that is what RKT does with their custom design pistons as well. I believe the wrist pin location and piston clearance are the main key factors that are addressed in RKT piston kits.
--BTW, Doo 800 skirts are thinner than CFI2 skirts
--Cat skirts are not 37% thicker after bored out to 925cc
--CFI2 skirts are even thinner after bored out to 858cc
--Probably right about the CFI2 cylinder cooling issues
---Maybe---
--Turboed and modified CFI2 engines with stock pistons seem to be holding up longer because they make more power/heat thereby tightening up loose OEM clearances. If this is true, more OEM engines will blow operated by less aggressive riders and that are run in good snow for plenty of cooling. The cooler this engine operates-- the looser the piston clearance is -- the sooner the loose pistons are going to hammer the skirts off, aided by an improperly leveraged wrist pin location.
--So to fix top end of CFI2--
--Redesign cylinders/cooling system for better, more even cooling
--Redesign piston for proper clearance and wrist pin location
--or else just keep selling extended warranties
--BTW, Doo 800 skirts are thinner than CFI2 skirts
--Cat skirts are not 37% thicker after bored out to 925cc
--CFI2 skirts are even thinner after bored out to 858cc
--Probably right about the CFI2 cylinder cooling issues
---Maybe---
--Turboed and modified CFI2 engines with stock pistons seem to be holding up longer because they make more power/heat thereby tightening up loose OEM clearances. If this is true, more OEM engines will blow operated by less aggressive riders and that are run in good snow for plenty of cooling. The cooler this engine operates-- the looser the piston clearance is -- the sooner the loose pistons are going to hammer the skirts off, aided by an improperly leveraged wrist pin location.
--So to fix top end of CFI2--
--Redesign cylinders/cooling system for better, more even cooling
--Redesign piston for proper clearance and wrist pin location
--or else just keep selling extended warranties
P
pura vida
Well-known member
if that is the case and actually true why doesn't kelsey state that and point that out ending the conversation? instead he snipes at anyone that might in any way criticize him.
pv
simply tightening cylinder bore clearence with a bigger piston doesnt fix it either...not on the cfi motors..polaris already tried that...piston swells and squeaks... and here is what kelsey posted when he wanted a low alt tester for his 858....
Looking for a low alt 858 tester
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Preferrably Alaska sled.. Must be a 2011 Pro.
Would like to offer a smokin' deal (NOT FREE) to have somebody test the 858 kit at the low elevation.
I have a 2011 cylinder ready to go.
Let me know if any of you AK riders have any interest in this. Minimal down time, just in back and forth shipping time... Will need you stock cylinder and your exhaust valves.. You will need a boondocker box (not supplied at this time)
Let me know
Thanks
Kelsey
Im I the only one that sees silicone sealer on the inner head o-ring?
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X2Freeride
Well-known member
With the turbo your forcing so much air/fuel through the engine that it negates any cooling issues you may have. Which makes up for the lack of cooling you have on a NA sled.
that hurts..lol..a see my bank account sinking reading that if i ever got a turbo...lol..
Quote:
Originally Posted by rkm
Im I the only one that sees silicone sealer on the inner head o-ring?
This is never a good idea, it is more likely to cause a long term leak path than not. If you need something to hold the O-ring in place because you want to re-use it and stretched it when you cleaned it, use a light film of grease to hold it long enough to bolt the head on. You should never use silicone or RTV with O-rings.
It is also a better idea to use a very light film of grease on gaskets so that you can re-use them. I never use RTV and a gasket as it negates the need for a gasket at all and in most case cases the gasket to slip and leak, as it is now floating on the RTV that regardless of the torque applied the mating parts can not get a bite or crush on the gasket that provides the sealing.
Originally Posted by rkm
Im I the only one that sees silicone sealer on the inner head o-ring?
This is never a good idea, it is more likely to cause a long term leak path than not. If you need something to hold the O-ring in place because you want to re-use it and stretched it when you cleaned it, use a light film of grease to hold it long enough to bolt the head on. You should never use silicone or RTV with O-rings.
It is also a better idea to use a very light film of grease on gaskets so that you can re-use them. I never use RTV and a gasket as it negates the need for a gasket at all and in most case cases the gasket to slip and leak, as it is now floating on the RTV that regardless of the torque applied the mating parts can not get a bite or crush on the gasket that provides the sealing.
