3250 top end is fine but it is in getting a new crank thanks to a broken primary
Fix Kits!
- Thread starter Coleniuk
- Start date
Yes, nice and fast !! LoL !!
First of all there is no piston I have ever seen thats stronger then the OEM Polaris piston in dragon/Pro Motor.
To answer the question of thread title.
If you take 10 - 1000 mile Dragon motors, and 10 - 1000 mile Pro Motor.
Lets just say for the sake of averages all the cylinders measure 3.3475 at the bottom & all are alittle tighter at the top. ( Strange but this is the way they are.
Then measure all the OEM Pistons ( They will be from 3.330 to 3.338 )
Most will be in 3.335 area. ( Thats .0125 thou clearance ) .0045 past service manual spes for rebuild time.
Now that being said - if you buy any fix-it-kit, or drop in kit, or you simply sit down on throne and get out the visa card and open the Dennis Kirk catalog and buy the cheapest lemans parts unlimited brand piston and budget gasket kit
And then buy a POS dingle ball hone and throw them together.....
Then tell all 20 sled owners to go get on them and let them warm up for 10 minutes and hold them wide open for a 1/2 miles then slow down and punch them in the midrange a few times to chk throttle response ( all 20 will say the same thing ? ) WOW !!! This thing runs awesome!
Now repeat the exact same rebuild except strip the cylinder and tighten it up the .0045 thou and now put every piston kit knowen to man kind in these sleds and repeat the 10 minute warm up and full throttle for 1/2 mile.
What will be the results now ??
1) - They will ALL idle better.
2) - They will ALL punch harder.
3) - All the Cast Pistons will make the 1/2 mile
4) - Zero Forged pistons will make it the 1/2 mile @.004 thou clearnace.
then throw a Turbo in the mix and they won't live @ .0055
Moral of the story
1)-Any piston that is new, and has OEM new measurement skirt will run awesome and will not seize As long as you leave the cylinder alone and do NOT replate & size it correctly.
2) -In OEM Form the Small Block 800 is the most forgiving motor to put pistons in because the cylinders are to big when they are new.
3) - The Problem with the above tactic is this ( The Pistons don't last )
with a cylinder that loose no matter whos it is. ( When I say The Pistons won't last I mean it will not hold skirt tollerance and the motor will loose power because the piston is not keeping the ring face square to the bore.
( This is the point where people start chasing their tails with clutching and fuel programmers ) trying to tune a woren out motor.
4) -The Piston goes up & down 137 times per second.
That means the reeds open & close 137 times
In Theroy the pistons, the reeds, the air ( Flow ) has to start and stop 137 times per second.
I really see lots of threads out there that are titled ( Air flow Problems
with IndyDan's Cylinders. )
I build the motors to last and i warranty them for 3 years no matter how many miles you ride.
I do not post a HP Number on my motors and neither does Carls cycle.
( Example ) Ok I dynoed a used never taken apart Dragon 800 it made 122hp, I completely rebuild it ( reinforced the cylinder skirts ) then dynoed it..... It made 152hp.
WOW !! HOLY COW !! INDYDAN'S MOTORS MAKES 30 HP MORE THEN STOCK !!
Is that how i am suppose to market my motors ?
Not in my book......There are plenty shops with buddies that run to SW with HOLY COW stories about their new HOLY COW BIG BORE STUFF !! AND WOW ITS AWESOME !!
Staged !! Alot of staged stuff on here.
Dan's stuff..............Never staged. people buy, they ride, they talk.
People have mentioned they do not want this turned into back & forth bash thread.
Last winter I rebuilt a 2009 800 Dragon with 12,000 miles on it and it had never been apart. OEM cast piston imagin that. the motor doesn't have a piston problem. Its been proven. ( Most have a clearance problem. ) Its been proven...... I measure them everyday.
Has one person ever posted a new cylinder actual size or clearnace other then me ??
95 + % of the dealers accross the country do not have bore guages.
1 made Post - And i hope its the last time on this thread.
Dan
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9
96sherm
Member
New snowest user here...not a new sledder. I recently had to rebuild my motor (top and bottom) after it spit out the cage of the PTO side crank bearing, resulting in "cold seize" on the PTO side piston/cylinder. Sled had 2442 hard miles on it. I rebuild it with RKTek Pistons and 13:1 head. One huge plus I find to the RKTek stuff is that the Wossner pistons were a full 38g lighter than the factory pistons, and 100% equal in weight. Factory pistons were 2g different. I didn't like the idea of the "fix kits" with a 1/4" spacer between the cylinder and base, to me creating another seam is asking for another issue (tho I realize many peeps have used these kits without fail, I don't feel it was the way to go for me). I've put on 3-400 mountain miles since the rebuild and I'm very impressed and happy with the increase in power, quicker throttle response, increase in rpm, and smooth running...
For me, best 800$ spent.
For me, best 800$ spent.
Is that 3000 stock motor miles or drop in kit miles.
But why would you run the forged piston at the non recommended clearance?? Of course its going to seize if its not to spec. Cold start forged vs cast I can see the forged having more blow by but once warmed up Id rather have the forged... Now my opinion really doesnt matter that much because I dont build engines for a living but I do know forged is stronger than cast and in theory should handle more of a beating and last longer...
Now on a different note as stated before none of the fix kits match the pistons to your cylinders. How many fix kits are blowing up? I havent heard of any so one would assume polaris was consistant on the bores but not on the pistons. Now mind you I dont get along with kelsey all that much but I dont think his wossner pistons are the best piston you can buy. If I was keeping my polaris Id throw a set in vs the cylinder shim, cat piston fix..
I believe you do not know.
Simple test - take a factory cast piston and put it in a press ( skirt end ) apply pressure until it crushes .015
Then repeat this proccess with a forged piston and report your findings to this thread.
I can tell you what happens if you continue to press.
The Cast piston will bend and then snap.
The forged piston will just bend until there is nothing left to press.
forged are softer not stronger ( sometimes this is a good thing ) Most forged pistons have really good Japan rings that are not brittle and don't break and trash turbos. ( I had better luck with forged in my Turbo 700 BB AFTER i add .002 clearance ) soft mean less silicon and more expansion.
Cast pistons and stronger and expand less.
I have stuck more forged pistons then 50 average sleds added together.
at above average clearance.
.004 to .0055 is factory spec.
If you put a turbo or nitrous on a SB 800 with .0055 clearance with a forged piston and let it have it @ full trottle for a 1/4 mile they stick 9 out of 10 times.
The stock 800 cylinder at factory clearance is a dream come true for a forged piston.
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Great comments here...
Some good people making good products they believe in... sometimes, different ways to bake a cake.
Please keep it respectful and reasonable.
Kelsey and Dan, You both are talented engine people... And passionate about the engine kits you make and your methods. Same for the others at MTNTK and Nortstar etc...
Please lets make this a constructive thread... no need to "tear down" the other to prove your points.
Nothing wrong with a good debate though..
.
Rock on!
Some good people making good products they believe in... sometimes, different ways to bake a cake.
Please keep it respectful and reasonable.
Kelsey and Dan, You both are talented engine people... And passionate about the engine kits you make and your methods. Same for the others at MTNTK and Nortstar etc...
Please lets make this a constructive thread... no need to "tear down" the other to prove your points.
Nothing wrong with a good debate though..
.
Rock on!
S
scott t
Active member
I have a 2012 switchback assault with 1 season left on warranty. I plan on doing one of these kits also just before warranty ends. I am not an engine guy so i am trying to understand this engine issue. So what i understand is that its not a problem with the piston but a problem with the piston clearance causing fatigue on the skirts. So after another season of riding lets say i go with just a piston kit from whoever. Is there anyway to know how fatigued my cylinder skirts may already be? Even though I throw a piston in that vibrates less and runs smoother, has there already been damage that may show up shortly after that or would you know from looking at the cylinders? Like I said im not an engine guy so these questions may seem weird or dumb, but just looking for info to best decide on what route i want to go.
The only true way is to send them out and have them stripped and re nicacil . You can look for cracks but some are hard to see if you do not know what you are looking for . It will run a little over $300 but when you get them back they are like new or better.
I believe Indy Dan or Kelsey offer this also.
I believe Indy Dan or Kelsey offer this also.
D
dmj1
Well-known member
pistons
I have built and ran lots of motors turbo-ed and non turbo-ed ..
I have tried both cast and forged pistons ...
I now only use factory cast pistons ... last longer and take more abuse..
I believe factory Polaris cast pistons have close to 18% silicone in them .
This is why they take the heat and don't get soft..
Just my opinion ...
I have built and ran lots of motors turbo-ed and non turbo-ed ..
I have tried both cast and forged pistons ...
I now only use factory cast pistons ... last longer and take more abuse..
I believe factory Polaris cast pistons have close to 18% silicone in them .
This is why they take the heat and don't get soft..
Just my opinion ...
Overall I respect Dan's engine experience and surely his work is quite good but Dan your pride is sometimes a little much. To make a blanket statement about Polaris dealers like you did goes abit overboard. The common guy after reading that would not go to a dealer for engine work knowing that they didn't have nor use the proper tools when working on an engine. Of the 6 closest dealers around me I'd say 95% do mic the jugs and also have a torque wrench and use it. Also most of the dealers around me are sledders and raced at some form years back and now have great service shops. It's about the love of the product and not having come backs that builds our pride. We too know a little bit sir.
R
RKT
Well-known member
1/4 mile pulls on the lake in MN, MI, WI NY etc..... What would that be in terms of "time"?? I am figuring between 11-15 seconds WOT..??? Correct??We, in the Mountains, regularly make WOT pulls lasting upwards of 60 seconds and 15 second WOT pulls are on the low side and done dozens of times every outing... Again, the "norm" is closer to 30-60 second WOT pulls FULLY LOADED in frigid temps (usually below zero F)
These common WOT pulls are done with ALL 3 two stroke brands and done with Big Bores AND TURBOS... again... VERY common. Nitrous.. Not so common anymore in the mountains.. But there are still some rockin' the Nitrous..
These WOT pulls are done with our very custom forged pistons...
These pulls do NOT result in piston or engine failure...
So, the idea that a forged piston will NEVER live at tight tolerance on 15 sec loaded WOT pulls is simply not the case around here!!
Ya know, we even have much video footage to show this to be the case..
Feel free to check it out anytime .. https://www.youtube.com/user/torqueline/videos?view=0
Scroll on down to find the Big Bore 858 vids...
On that note: The skirts on the 858 Big Bore are thinner than the stock cylinder skirts (obviously because the cylinder is bore out larger)
YET... There have been ZERO accounts of cylinder or piston skirt breakage/cracking.. etc...
Same with the Drop In or Direct Replacement Pistons that we offer..Yet, the stock cylinder at a thicker skirt thickness and stock piston will suffer failure..
(I get those calls every single day..)If the Piston is NOT the problem, then why does changing out the piston stop the failures?
Why would one need to weld the skirt (effectively reducing air flow..this can NOT be disputed) or increase the rod length to fix a problem that is obviously cured with a better piston?
Thanks !!! But it's all just little basic shop stuff meaning I really shouldn't be going but I am going anyway !! LoL !!!
Rmk727 I must apologize for the way I set up that post , the dealers around here are a lot less supplied in the tool department than where you're from. I do apologize for that and I did not mean it to intend as a slam to polaris dealers more on the line of Polaris does not set their dealers up correctly & instruct them how to measure size, check crank run-out . And the customer does not get a fair shake on their motor. I did not mean it as a slam again I am sorry how I said that.
I think you guys are the 5%...... I have been doing this since i was a kid and have never seen a dealer with a bore gage.
Dan
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Oh boy!!! I just started using Tapatalk and I don't know how that part of the message got into that post but I was sending that to somebody else that wanted to meet out West To go riding.
And then I was using voice talk on top of that and I just got back and read the post OH MY GOD !!!
I Editted the slurrrrrrrrr and Blurrrrrr
Sorry !!! LOL!!
Dan
And then I was using voice talk on top of that and I just got back and read the post OH MY GOD !!!
I Editted the slurrrrrrrrr and Blurrrrrr
Sorry !!! LOL!!
Dan
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We, in the Mountains, regularly make WOT pulls lasting upwards of 60 seconds and 15 second WOT pulls are on the low side and done dozens of times every outing... Again, the "norm" is closer to 30-60 second WOT pulls FULLY LOADED in frigid temps (usually below zero F) I have plenty of customers from Utah.......Many of them know you and sum of them have riden with you and see you and your clan at the same play area you most often go to. But you have a reputation of making 1 or 2 climbs and then sit at the bottom of the him watching other people ride. ( My customers.......RIDE !!! and put thousands of mountain miles on their sleds. ) - Plain and simple that is why I do so much work to the motor to make it last. Your a go fast shop.......I use to be just a go fast shop. Go fast customers sit around talking about how great their stuff is. ( and normaly ride less ) My customers are riding the piss out of their sleds.
3 Year warranty. ( Thats why ) Different crowd. Not bad, just different.
We are also offering a 5 year warranty Guide Motor this summer.
These common WOT pulls are done with ALL 3 two stroke brands and done with Big Bores AND TURBOS... again... VERY common. Nitrous.. Not so common anymore in the mountains.. But there are still some rockin' the Nitrous..
These WOT pulls are done with our very custom forged pistons...
These pulls do NOT result in piston or engine failure...
So, the idea that a forged piston will NEVER live at tight tolerance on 15 sec loaded WOT pulls is simply not the case around here!! As I said I have been down the forged road and I wouldn't build a motor EVER with a forged piston and warranty any part of it.
Ya know, we even have much video footage to show this to be the case..
Feel free to check it out anytime .. https://www.youtube.com/user/torqueline/videos?view=0
Scroll on down to find the Big Bore 858 vids...
On that note: The skirts on the 858 Big Bore are thinner than the stock cylinder skirts (obviously because the cylinder is bore out larger) I have a
858 cylinder here with both rear skirts missing thats getting welded up with 45 degree gussets. ( obviously then can break even with a soft forged piston )
YET... There have been ZERO accounts of cylinder or piston skirt breakage/cracking.. etc...
Yet, the stock cylinder at a thicker skirt thickness and stock piston will suffer failure..
If the Piston is NOT the problem, then why does changing out the piston stop the failures? Because the new piston has not yet been crushed from to much cylinder clearance and to short a rod ( If you stop the slapping soon enough you can make the cylinder last along time. )
( If Polaris didn't just figure out the rod ratio was sub-par ) They would not have moved the 2013 cylinder bore backwards to soften the angle of attack from the rod when it comes off the 6 o'clock position.
Why would one need to weld the skirt (effectively reducing air flow..this can NOT be disputed) or increase the rod length to fix a problem that is obviously cured with a better piston?
The gussets did not effect performance., and because I want MAXIMUM dependability.
If there wasn't a rod ratio problem Polaris would have NEVER re-tooled a complete new cylinder & crankcase for 2013. NEVER !
You can mark my work the 2013 motors will last WAY longer then the 08,09,10,11,12 motors with the exact same piston.
Its plain and simple..... its not a piston problem. ( Pistons are a patch )
To much clearance with a short rod. ( Bad combination. )
Dan does what Dan does.
RKT does what he does.
The end.
Dan
Dan, you and Kelsey are both doing all of us a favor by offering options. Thanks to both of you for this.
But neither of you will win this argument on Snowest, there are just to many backyard whana be mechanics on here that dont appreciate what you guys do.
But neither of you will win this argument on Snowest, there are just to many backyard whana be mechanics on here that dont appreciate what you guys do.
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R
RKT
Well-known member
Originally Posted by RKT
We, in the Mountains, regularly make WOT pulls lasting upwards of 60 seconds and 15 second WOT pulls are on the low side and done dozens of times every outing... Again, the "norm" is closer to 30-60 second WOT pulls FULLY LOADED in frigid temps (usually below zero F) I have plenty of customers from Utah.......Many of them know you and sum of them have riden with you and see you and your clan at the same play area you most often go to. But you have a reputation of making 1 or 2 climbs and then sit at the bottom of the him watching other people ride. ( My customers.......RIDE !!! and put thousands of mountain miles on their sleds. ) - Plain and simple that is why I do so much work to the motor to make it last. Your a go fast shop.......I use to be just a go fast shop. Go fast customers sit around talking about how great their stuff is. ( and normaly ride less ) My customers are riding the piss out of their sleds.
3 Year warranty. ( Thats why ) Different crowd. Not bad, just different.
Hey Dan.. I live and ride in IDAHO.. NOT UTAH!! As for your customers that ride where I do (in UTAH??)
We ride on off days (weekdays mainly) and usually never see another rider the ENTIRE DAY!!
So, Nice try.. but [X] Try harder next time ....
Honestly, you could not be FURTHER from the truth!!!
We are also offering a 5 year warranty Guide Motor this summer.
These common WOT pulls are done with ALL 3 two stroke brands and done with Big Bores AND TURBOS... again... VERY common. Nitrous.. Not so common anymore in the mountains.. But there are still some rockin' the Nitrous..
These WOT pulls are done with our very custom forged pistons...
These pulls do NOT result in piston or engine failure...
So, the idea that a forged piston will NEVER live at tight tolerance on 15 sec loaded WOT pulls is simply not the case around here!! As I said I have been down the forged road and I wouldn't build a motor EVER with a forged piston and warranty any part of it.
Yes, but I do.. and have been doing it for YEARS,,, So, maybe the forged piston you use just simply aint up to the task... We have seen that often.. that is why our pistons are custom made in their process and their geometry.. Your engine is only as good as its piston.. and you are 100% right.. some pistons (like the OEM) are simply not up to the task...Fortunately, we did the R&D to develop a piston that IS up to the task..
Ya know, we even have much video footage to show this to be the case..
Feel free to check it out anytime .. https://www.youtube.com/user/torqueline/videos?view=0
Scroll on down to find the Big Bore 858 vids...
Hey Dan.. Check out the videos... ALL of them.. see if you see ANY other tracks or riders in them??? Maybe your Utah riders that see us are Cloaked or their sleds do not make snow tracks????
On that note: The skirts on the 858 Big Bore are thinner than the stock cylinder skirts (obviously because the cylinder is bore out larger) I have a
858 cylinder here with both rear skirts missing thats getting welded up with 45 degree gussets. ( obviously then can break even with a soft forged piston )
Good for you, got any pics of it(piston and cylinder)?? Probably not one of mine.. But you can always hope...Or maybe I just do not believe you... Nah..
YET... There have been ZERO accounts of cylinder or piston skirt breakage/cracking.. etc...
Yet, the stock cylinder at a thicker skirt thickness and stock piston will suffer failure..
Fix it or get a new one... There is a difference between fixing a BROKEN cylinder and taking a perfectly good cylinder and welding on it... Agreed?
If the Piston is NOT the problem, then why does changing out the piston stop the failures? Because the new piston has not yet been crushed from to much cylinder clearance and to short a rod ( If you stop the slapping soon enough you can make the cylinder last along time. )
So, we are in agreeance.... the piston DOES fix the problem!!! awesome...
( If Polaris didn't just figure out the rod ratio was sub-par ) They would not have moved the 2013 cylinder bore backwards to soften the angle of attack from the rod when it comes off the 6 o'clock position.
AAHH.. Dan.. Polaris, did NOT move the cylinder back AT ALL... The bore is in the SAME place(with respect to the crank and case) as it was in 2011 and 2012...Sorry... but it is the truth... NO DIFFERENCE.. Where did you get this information??
Why would one need to weld the skirt (effectively reducing air flow..this can NOT be disputed) or increase the rod length to fix a problem that is obviously cured with a better piston?
Trying to be civil here.. but you have some really incorrect information... I have tried to clarify above in the Green
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