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Bore or boosted 850

N

NWaxys

Well-known member
Feb 28, 2016
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Eastern WA back country
Since the hay days news is out what do you think? Bored 850 or a boosted one? Let's hear your experiences w this?
I've only had boost. I will mod my 850 to match my boosted axys. ridecascade.com
 

DUKHTR3

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I have never had a big bore either. Only boosted and I don't think I could ever ride anything other then a turbo. They are just so much fun!!

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sledhead_24_7

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Jul 30, 2008
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Jackson Wy
That will be the question. Should be several good options.

Myself I thinking I'm going their way.
Pay close attention to bottom of the shop manual...

Had awesome results over the past 3 years.

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turboless terry

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Jan 15, 2008
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Big Timber, MT
Boost hands down. I had a tryg that blew up. Doesn't matter who's fault you think it was. I could have bought a turbo and a half for what I had into it. A turbo you are dealing with stock parts if you have trouble. It was over a month on big bore.
 

duncan76

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Aug 16, 2013
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central 509
Boost hands down. I had a tryg that blew up. Doesn't matter who's fault you think it was. I could have bought a turbo and a half for what I had into it. A turbo you are dealing with stock parts if you have trouble. It was over a month on big bore.

Boy you must run one cheap turbo system. My race gas 872 set me back $2300 and now has 2600 miles on it zero issues. I guess some people think there good with a wrench.
 
M

mtn mike on boost

Well-known member
Nov 26, 2007
1,498
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Woodinville,WA
I have had poor luck with both ( turbo was before the sport had them dialed)

I think ill stay mostly stock. I think the best $ spent would
be on a coil over skid, light weight can and hood
 
N

NWaxys

Well-known member
Feb 28, 2016
467
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Eastern WA back country
I plan on doing full exit shocks springs bm fab boards lower bars and tki belt drive. I just wanna know what option is better power wise. If my sleds don't make 200 hp or close they don't go where I need to
 

Reeb

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For the price difference.......hard to say no to a turbo. A Boondocker X on a stock motor and you're done. Turn the boost up or down depending on elevation and quality of fuel. No waiting around for pistons, jugs or heads if something does happen.

I don't care what any motor builder tells you, anything less than 1 liter isn't making within 10hp of 200hp. Not only that but for a true 200hp(corrected) motor to have any longevity is asking a lot. My Cutler 1 Liter BB NEEDS new pistons every 1000 miles otherwise the skirts break.(Ya it's a piston design issue, but those are mighty big pistons rocking back and forth on a small ringland. You can't ask for your cake and eat it too with this particular motor.(Not a Doo btw) And I'm not easy on it, it's constantly wicked) I've spent too many late nights drinking beers with guys that have been building BB's to know. My next sled is going boosted. I have a 4 stroke turbo and 3 BB 2s sleds....my next build will be a 2 stroke turbo. They have them down to a science now. Something these big bore engine builders have been trying to figure out for 30 years.

BTW a race gas 872 with 2600 miles and not even a new top end is just asking for catastrophic failure. We can barely get stock 800 Rotax's to live 2500miles before a complete teardown and rebuild is in order.(2500miles is roughly close to 4000km right?) I know the PNW doesn't get much powder so you might not be as 'hard' as we are on motors but you're flirting with the devil(and a tow rope) pushing that Rotax that far. The old Ptecs wouldn't last past 3000KM for us, the Etecs are barely making 4000KM unless they get trail ridden or spring snow ridden lots. I've only seen a handful last past 5000KM without any maintenance that have lived 50/50 easy/hard lives. Maybe we got shatty fuel up here in BC and AB? Either way, a whistle will be on my next sled.

Edit: Oh the majority of this post was a response to old Duncan in the 509 btw. Not looking to get into an argument, just an observation of what our dealer network sees up here.
(Then of course there's those "brand Ambassadors" that are on here once in a while that claim 10,000km without even changing a belt......so hard to tell what's real and what's smoke unless you see what multiple dealers are faced with year in and year out.)
 
Last edited:

duncan76

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For the price difference.......hard to say no to a turbo. A Boondocker X on a stock motor and you're done. Turn the boost up or down depending on elevation and quality of fuel. No waiting around for pistons, jugs or heads if something does happen.

I don't care what any motor builder tells you, anything less than 1 liter isn't making within 10hp of 200hp. Not only that but for a true 200hp(corrected) motor to have any longevity is asking a lot. My Cutler 1 Liter BB NEEDS new pistons every 1000 miles otherwise the skirts break.(Ya it's a piston design issue, but those are mighty big pistons rocking back and forth on a small ringland. You can't ask for your cake and eat it too with this particular motor.(Not a Doo btw) And I'm not easy on it, it's constantly wicked) I've spent too many late nights drinking beers with guys that have been building BB's to know. My next sled is going boosted. I have a 4 stroke turbo and 3 BB 2s sleds....my next build will be a 2 stroke turbo. They have them down to a science now. Something these big bore engine builders have been trying to figure out for 30 years.

BTW a race gas 872 with 2600 miles and not even a new top end is just asking for catastrophic failure. We can barely get stock 800 Rotax's to live 2500miles before a complete teardown and rebuild is in order.(2500miles is roughly close to 4000km right?) I know the PNW doesn't get much powder so you might not be as 'hard' as we are on motors but you're flirting with the devil(and a tow rope) pushing that Rotax that far. The old Ptecs wouldn't last past 3000KM for us, the Etecs are barely making 4000KM unless they get trail ridden or spring snow ridden lots. I've only seen a handful last past 5000KM without any maintenance that have lived 50/50 easy/hard lives. Maybe we got shatty fuel up here in BC and AB? Either way, a whistle will be on my next sled.

Edit: Oh the majority of this post was a response to old Duncan in the 509 btw. Not looking to get into an argument, just an observation of what our dealer network sees up here.
(Then of course there's those "brand Ambassadors" that are on here once in a while that claim 10,000km without even changing a belt......so hard to tell what's real and what's smoke unless you see what multiple dealers are faced with year in and year out.)

Yip it must be your gas. The original 2008 r motor had 5500 miles on it before I got a short block and big bored it put 2000 miles on it before I did tms piston update and never an issue. Maybe I'm just lucky IDK but I will not hesitate to put a bb in my 18 when I check it this spring. BTW I've been up in your neck of the woods and Idaho Montana so the sled is rode hard since day one. Like I said maybe I am just lucky. Please snow.
 

rulonjj

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capitol town, WY
For the price difference.......hard to say no to a turbo. A Boondocker X on a stock motor and you're done. Turn the boost up or down depending on elevation and quality of fuel. No waiting around for pistons, jugs or heads if something does happen.

I don't care what any motor builder tells you, anything less than 1 liter isn't making within 10hp of 200hp. Not only that but for a true 200hp(corrected) motor to have any longevity is asking a lot. My Cutler 1 Liter BB NEEDS new pistons every 1000 miles otherwise the skirts break.(Ya it's a piston design issue, but those are mighty big pistons rocking back and forth on a small ringland. You can't ask for your cake and eat it too with this particular motor.(Not a Doo btw) And I'm not easy on it, it's constantly wicked) I've spent too many late nights drinking beers with guys that have been building BB's to know. My next sled is going boosted. I have a 4 stroke turbo and 3 BB 2s sleds....my next build will be a 2 stroke turbo. They have them down to a science now. Something these big bore engine builders have been trying to figure out for 30 years.

BTW a race gas 872 with 2600 miles and not even a new top end is just asking for catastrophic failure. We can barely get stock 800 Rotax's to live 2500miles before a complete teardown and rebuild is in order.(2500miles is roughly close to 4000km right?) I know the PNW doesn't get much powder so you might not be as 'hard' as we are on motors but you're flirting with the devil(and a tow rope) pushing that Rotax that far. The old Ptecs wouldn't last past 3000KM for us, the Etecs are barely making 4000KM unless they get trail ridden or spring snow ridden lots. I've only seen a handful last past 5000KM without any maintenance that have lived 50/50 easy/hard lives. Maybe we got shatty fuel up here in BC and AB? Either way, a whistle will be on my next sled.

Edit: Oh the majority of this post was a response to old Duncan in the 509 btw. Not looking to get into an argument, just an observation of what our dealer network sees up here.
(Then of course there's those "brand Ambassadors" that are on here once in a while that claim 10,000km without even changing a belt......so hard to tell what's real and what's smoke unless you see what multiple dealers are faced with year in and year out.)

I know of several etecs n/a and turboed with over 3000 miles on a completely stock engine with no rebuilds. Maybe it's your fuel. Felker has told me he has a few with over 5,000 miles on factory engines. I've actually never seen an etec go down and I ride with 15 different etecs throughout the season.
 

Reeb

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I know of several etecs n/a and turboed with over 3000 miles on a completely stock engine with no rebuilds. Maybe it's your fuel. Felker has told me he has a few with over 5,000 miles on factory engines. I've actually never seen an etec go down and I ride with 15 different etecs throughout the season.



We wish. Our area dealers sell probably 500 Summits combined yearly and unless they are ridden easier and/or the guys are inflating numbers they never see 5000miles. Don't get me wrong, there are those few that have 10k KM on them but they aren't ridden hard at all. I've seen and even been on a couple that have had catastrophic failures. I've actually been on both ends of the tow rope with an Etec on the other end.

I doubt my next sled will be anything other than a Doo. We'll see how my first Polaris since my 2001 Pro-X 440 holds up this year. I'm very skeptical but willing to give it a try simply because I wanted to give the 850 a year to iron things out.


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Goinboardin

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Nov 15, 2009
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Laramie, WY
I'm at 3250 on a stock engine Etec 800 (2013). Runs well now but I'm right at 295 hours of run time. I'm not a trail rider but certainly not the hardest rider on equipment out there (well, my sleds appearance may make me a contender! ha). Warranty is up November 15th so I'll be scrutinizing this motor before I let that lapse. Compression, crank run-out, and pull head. I don't like blowing things up, rather do preventative work, but I also don't like throwing money down the drain needlessly.
 

cubby

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Nov 26, 2007
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Yip it must be your gas. The original 2008 r motor had 5500 miles on it before I got a short block and big bored it put 2000 miles on it before I did tms piston update and never an issue. Maybe I'm just lucky IDK but I will not hesitate to put a bb in my 18 when I check it this spring. BTW I've been up in your neck of the woods and Idaho Montana so the sled is rode hard since day one. Like I said maybe I am just lucky. Please snow.

So with 5500,miles plus 2000 miles before pistons and 2600 miles after the rebuild you have close to 10000 miles on that sled and it's still holding togather? That's a lot of miles on a chassis
 

duncan76

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So with 5500,miles plus 2000 miles before pistons and 2600 miles after the rebuild you have close to 10000 miles on that sled and it's still holding togather? That's a lot of miles on a chassis

Your close 5500 then new motor with bb. 2000 miles new top end. Then over 600 last year. That is why I will more than likely snow check for 18. Then yes I will bb again being that my current one runs every bit as good as it did when it was stock just with alot more power.:face-icon-small-hap
 
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