850 big bores? No talk all season about them?

FEZ · Apr 18, 2018

Bacon said:
Is there a reason your jumping between kits or are you selling all of them?

Supporting as many customers as we can one must test/tune/run what is out there and what customers want. Clutching is a major issue with the Gen4 and SHR has developed its' own adjustable weights to again, help as many customers get the most out of their Doo for whatever application they may have

sledsrock · Apr 18, 2018

N2O

christopher said:
I see three issues that are at play in the Turbo vs. Big Bore situation.

#1.
Turbos have come a LOOOONG ways in technology and reliability in the last several years. They are FAR more accessable to the normal rider now than at any other time in the past.

#2.
Pretty much any rider can install a turbo kit over the weekend.
Converting your 850 over to a Big Bore means your engine is coming out of the sled.

#3.
The ONLY way to compensate for lost power at higher elevation is FORCED INDUCTION. There is simply no other mechanical solution to lowered ambient pressure as we climb the mountain.
Only a Turbo/Supercharger can overcome that loss.

NITROUS.

turbo800 · Apr 18, 2018

sledsrock said:
NITROUS.

***GASP*** WHAT!!

All joking aside, many people probably forget that Boondocker made it roots early on in the N2O market. Do they even offer it anymore?

jim · Apr 18, 2018

Up to 6000 feet a big bore might make sense. Above that is turbo territory.

Nailed it.

Yeah, big bores can and do work at elevation as well...but you can only do so much to make up for the elevation. Forced induction is the only way to get around it.

mtncat · Apr 18, 2018

2 Seasons? Mine had a power commander the first season, not one single ride without setting check engine lights and limp mode!! have also been around the new and improved dobeck box on the 927, have heard that the silber reflash is
better than your new box but have not been around one yet, A/F gauges are available to the consumer and actually work to get fuel correct!! How about a guy out of Canada, Steve Roy had a 927 the beginning of this season and has since moved on as it would never out perform a well setup stock sled after the 330ft mark, any one can contact Steve VIA facebook and he would be glad to fill you in on all of there test results, it also had the supplied TMS fuel box and map for it to perform at its peak as stated above.

sledsrock · Apr 18, 2018

turbo800 said:
***GASP*** WHAT!!

All joking aside, many people probably forget that Boondocker made it roots early on in the N2O market. Do they even offer it anymore?

I’m not sure if “kits” are still made today. Been a few years since I have ran it. Used to make my own kits using NX Express parts. A true wet kit is quite fun really. Hard to clutch for on a mountain sled, if your ok with the over rev it’s a hoot. If my 880 didn’t spin at 8500 already I’d have a bottle on it too.

sledhead_24_7 · Apr 18, 2018

Nitrous worked great on all the older stuff due to the REV limiter being 9000 RPM.

The new stuff is all very limited on the “allowable” over REV. So pretty much pointless in a Mountain situation. Just can’t “click” down enough to make it worth it.

Though it sure was fun on the old bombers.

BIG JOHN · Apr 19, 2018

Bacon said:
Is there a reason your jumping between kits or are you selling all of them?

we are a multi line aftermarket dealer for skidoo/polaris sleds...

exhaust, clutching, tracks, suspension and turbos...

we "test n tune" and then sell with confidence in the product...BJ

BIG JOHN · Apr 19, 2018

fynnigan said:
Yup Tms seems to be not so good at standing behind some of their product ,we did 2 872s a couple of years ago , professionally installed ,proper fuel etc. . 1 has run very well the other has been a pos . Lots of base gasket issues ,2 burn downs , keeps,blaming it on the install .bs , skidoo certified tec did all the work .wont give a straight answer on torque spec for the jug ,instructions say 26 lbs. factory is 35 . When we did the first 1 the squish was different from 1 hole to the other ,a lot different .any ways he won’t be getting any more of our money . Oh yeah we heard the hillbilly thing to

NOT sure what you guys (??) are reading or from where but...

800R (all) 38 lb ft on cylinder, 21 head, 18 knock

600HO/800HO (all) 28 cylinder, 21 head, 18 knock

never lost a BG..........ever*

*there was 1 guy in AK, but after a phone call or 2 I found out he did not own a torque wrench.............BJ

Bacon · Apr 19, 2018

BIG JOHN said:
we are a multi line aftermarket dealer for skidoo/polaris sleds...

exhaust, clutching, tracks, suspension and turbos...

we "test n tune" and then sell with confidence in the product...BJ

Gotcha. Just seems most places concentrate on one brand turbo kit. Thought maybe there were issues with some of the manufacturers. Sure is nice to have options.

fynnigan · Apr 19, 2018

BIG JOHN said:
NOT sure what you guys (??) are reading or from where but...

800R (all) 38 lb ft on cylinder, 21 head, 18 knock

600HO/800HO (all) 28 cylinder, 21 head, 18 knock

never lost a BG..........ever*

*there was 1 guy in AK, but after a phone call or 2 I found out he did not own a torque wrench.............BJ

Get a hold of a set of install instructions from tms ,I know you are best of friends,lol , and have a look . Like I said one of them has been perfect the other has been very troublesome, could never get the squish right .and this was done at the dealer . The tight one burnt down twice even with a thicker base gasket

christopher · Apr 19, 2018

sledsrock said:
NITROUS.

Okay
No argument
But man, VERY SHORT term use and VERY HIGH COST.

Is that really a practical solution for long term power?

JJ_0909 · Apr 19, 2018

christopher said:
Okay
No argument
But man, VERY SHORT term use and VERY HIGH COST.

Is that really a practical solution for long term power?

Take a look at what the snow bikes are doing. 100% can be a long term solution depending on fuel management and how much access you have to the gas.

BIG JOHN · Apr 20, 2018

fynnigan said:
Get a hold of a set of install instructions from tms ,I know you are best of friends,lol , and have a look . Like I said one of them has been perfect the other has been very troublesome, could never get the squish right .and this was done at the dealer . The tight one burnt down twice even with a thicker base gasket

if it doesnt say 38+ lb ft its wrong...period

SHR recommends 38-40 lb ft...

as for squish? .040" is a safe number if the head was cut right (verify bore diameter of head:face-icon-small-win)...

.040" is deck height + step in head + dome drop (.002")

use base gasket to get the deck height desired to equal .040" total...BJ

sledsrock · Apr 20, 2018

christopher said:
Okay
No argument
But man, VERY SHORT term use and VERY HIGH COST.

Is that really a practical solution for long term power?

If set up correctly and don’t get too greedy it sure can be 100% usable long term. You’re not on boost 100% are you?

mtncat · Apr 26, 2018

Hard to believe the dyno sheet posted as I have a new OEM top end and 927 top end sitting side by side on the bench, run through and compare all ports from OEM to the 927, all port height is the same as a stock 850 with the exception of the rear port in front of reed valves is 1.5mm lower, so where does this magical 192+ HP and 132+ Trq come from? so here is what I found for fueling on the 927 and what finally made it run. Y pipe light coat of oil and dark brown, main pipe light coat of oil for about 10 inches turning to a light dry brown through the rest of the pipe, fueling I used for the last 950 miles----- Stock!!!---AFR#s at WOT 13:1, wash on pistons now that it is apart about 5/16-3/8 of an inch, this is the only way my 927 would run down the stock 850's if they got the jump on me. there were more side by side comparisons with this sled than any other I have owned trying to get it to pull like it should, add fuel and there is no catching the 850"s

kiliki · Apr 26, 2018

The fuel map and the primary clutch weight do not lie

sledsrock · Apr 27, 2018

mtncat said:
Hard to believe the dyno sheet posted as I have a new OEM top end and 927 top end sitting side by side on the bench, run through and compare all ports from OEM to the 927, all port height is the same as a stock 850 with the exception of the rear port in front of reed valves is 1.5mm lower, so where does this magical 192+ HP and 132+ Trq come from? so here is what I found for fueling on the 927 and what finally made it run. Y pipe light coat of oil and dark brown, main pipe light coat of oil for about 10 inches turning to a light dry brown through the rest of the pipe, fueling I used for the last 950 miles----- Stock!!!---AFR#s at WOT 13:1, wash on pistons now that it is apart about 5/16-3/8 of an inch, this is the only way my 927 would run down the stock 850's if they got the jump on me. there were more side by side comparisons with this sled than any other I have owned trying to get it to pull like it should, add fuel and there is no catching the 850"s

And here I thought more power always = more fuel. Dumb me.

Matte Murder · May 4, 2018

Chadly said:
I've been saying this ever since I first rode a BB. The money and hassle of still having to run race gas is not worth the measly power increase. Turbos smoke BB's on the mountain.

You’ve had 2-3 turbo sleds over the last few years. How many good rides have you had in total??? I think you told me about 1 this year. Most people don’t have near as much issues as you but turbos have a LOT OF ISSUES. Of the 4 Trygstad Big bores I’ve done I NEVER had ANY issue. Not a single one. I still have one(2015 174), and two of my buddies have the first two I built. Those where 2013 XMs. One got new pistons at 2200 miles and still rips. Dave recommended 1800 miles and that is spot on. Owner went about 200 miles too far. He was burning oil and losing power. It never broke tho and the owner of that sled is rediculously hard on sleds. The fourth one went to Alaska a couple years ago and I’ve lost track of it.
My 174 872 XM with about 1300 miles has at least as much power as my 2018 175 850 with 500 miles.
Chadly the fuel mixing comment cracks me up. I buy 20 gallons of race gas at the pump. I put approximately 1 gallon per 5. Either put a gallon in a fuel jug, just pour it in the tank while fueling from the pump or put 10 gallons in my 60 gallon tank on board the trailer. Couldn’t be easier. 20 gal of race gives me 100 or more gallons of fuel for the sleds. That’s a ton of riding.

Chadly · May 4, 2018

Matte Murder said:
You’ve had 2-3 turbo sleds over the last few years. How many good rides have you had in total??? I think you told me about 1 this year. Most people don’t have near as much issues as you but turbos have a LOT OF ISSUES. Of the 4 Trygstad Big bores I’ve done I NEVER had ANY issue. Not a single one. I still have one(2015 174), and two of my buddies have the first two I built. Those where 2013 XMs. One got new pistons at 2200 miles and still rips. Dave recommended 1800 miles and that is spot on. Owner went about 200 miles too far. He was burning oil and losing power. It never broke tho and the owner of that sled is rediculously hard on sleds. The fourth one went to Alaska a couple years ago and I’ve lost track of it.
My 174 872 XM with about 1300 miles has at least as much power as my 2018 175 850 with 500 miles.
Chadly the fuel mixing comment cracks me up. I buy 20 gallons of race gas at the pump. I put approximately 1 gallon per 5. Either put a gallon in a fuel jug, just pour it in the tank while fueling from the pump or put 10 gallons in my 60 gallon tank on board the trailer. Couldn’t be easier. 20 gal of race gives me 100 or more gallons of fuel for the sleds. That’s a ton of riding.

And the big bores of yours I rode are like a half horse power more than my stocker. I've never been so unimpressed in my life. They are a huge waste of money.

850 big bores? No talk all season about them?

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