You mean "Whore Snow" right ? 
.....And you correct for you $$$$ you will get just that "a LITTLE more"
OT
.....And you correct for you $$$$ you will get just that "a LITTLE more" OT
XP big bores - lets compare
- Thread starter deaner
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Been riding BB 880 for two years, the BB /stock 800 is same relationship as a 800/600 sled ,Yes even at 10,000 feet.The Torque is incredable as well !What does a Dyno measure? And the formula for HP derived from this measurement is ???
You know that you don't get more HP with more torque...HP is mathematically calculated from measuring torque.
By the way, we have chest deep snow here too...but not that light fluffy girly stuff....we have "MAN SNOW"....LOL
I'm just hoping the 860 gives me "a little more" that's alll that is claimed and all I expect.
Who's kit?
I feel a poem appropriate.
Nailing Jello To The Tree
Nailing Jello to the Tree
With Great Effort,
I call upon my Buddha Ancestors
To rescue me from Foolishness
And Confusion.
I hear them laughing in the bleachers.
One passes popcorn to the others.
Dhyan
Nailing Jello To The Tree
Nailing Jello to the Tree
With Great Effort,
I call upon my Buddha Ancestors
To rescue me from Foolishness
And Confusion.
I hear them laughing in the bleachers.
One passes popcorn to the others.
Dhyan
R
RKT
Well-known member
I feel a poem appropriate.
Nailing Jello To The Tree
Nailing Jello to the Tree
With Great Effort,
I call upon my Buddha Ancestors
To rescue me from Foolishness
And Confusion.
I hear them laughing in the bleachers.
One passes popcorn to the others.
Dhyan
ALL RIGHT.. THAT'S IT!!
Poems on SnowWest..
Brew.. I have to have some of those painkillers you are on..
Poet Brew, are you sure it's pain killers you need ? From the sound of things im thinking some Preperation H might be the best thing for your Hemeroids.
OT
OT
What Kelsey said! Brew....you are bent! LOL!
On the plus side, my SHR/RKT 880 is back together and ready to go!
On the plus side, my SHR/RKT 880 is back together and ready to go!
F
frog
Well-known member
What can't show the math.........
151 HP Stocker
@1000' = 146 HP
@2000' = 142 HP
@3000' = 137 HP
@4000' = 133 HP
@5000' = 129 HP
@6000' = 125 HP
@7000' = 122 HP
@8000' = 118 HP
@9000' = 114 HP
173 HP Big Bore
@1000' = 167 HP
@2000' = 162 HP
@3000' = 157 HP
@4000' = 153 HP
@5000' = 148 HP
@6000' = 144 HP
@7000' = 139 HP
@8000' = 135 HP
@9000' = 131 HP
At 9000' the BB has approx. 12.5% more power in optimun conditions " Hard Pack or Trail conditions..... IMHO, a 12.5 HP gain in chest deep snow isn't anything to be proud of
This was calculated at @3% and rounded off... Depending on the atmosphere/temps/conditions @ 9000' you can easily expect even less HP than posted.
OT
What about torque? Torque gets you there and HP keeps you there. The torque is what is getting you through the "chest deep snow" more than the HP is. Torque is widely overlooked and mostly unrealized by many riders. A 15% + increase in torque is going to be felt more than a 15% increase in HP in my opinion especially with the 800R being a little peaky compared to the old 800. When the engine is pulled hard and r's drop the torquer engine is going to recover quicker and allow the engine to run at peak rpm and HP quicker than the stocker.
Not flaming anyone just pointing out something that is rarely mentioned. I get a uncle stiffy when I have to increase my clutch weight to hold rpm's back to run at optimum HP instead of decreasing weight in order to get engine to run at proper RPM in order to achieve "advertised" HP.
At the hill drags this past april I ran against a XP with BJ's 860 kit and my XRS got the holeshot cause he was sleeping badly on the line and He drove by my easily and beat me by at least three lengths in a 500 ft drag goin up hill. Temps were in the 50 degree range and both sleds were running cold weather jetting. I spoke with the owner of the XP and he has done nothing to the sled since the 860 kit and was running everything that BJ recommended for clutching and jetting. Bottom line is that the sled was pull the rope and go and ran excellent with no issues.
Sucked to get beat but I was able to beat my buddies Assault everytime we raced so I was happy no matter what.
Tq=HPx5252/RPM.... any 2 engines with the same HP at the same RPM will always have the same torque at that RPM.....you cannot have more of 1 without more of both at a given RPM. HP is just a number derived from actually measuring torque.
R
RKT
Well-known member
Frog, with all due respect.. this is simply not true..
don't feel singled out... this is a HUGE misconception among most people..
I will try and explain, and I will generalize and keep it very simple..
1) Given 2 engines running at the same rpm.. if one engine has more HP, it automatically has more torque.. ALWAYS!! Torque is measured and HP is calculated via mathematical formula using TORQUE as one factor.
2)HP and torque can NOT be separated in terms of what is doing what with respect to how your engine runs (see #1).. They are connected ALWAYS and can not be separated..
3)Stating that torque is what is accelerating you down the track is simply incorrect.. Why? See #1 and #2 above..
Now, here is where the "FUN" begins...and hopefully, I can related to this Big Bore topic..
1st.. a few basics... Engines need to be clutched ALWAYS at peak HP rpms..
ANY good engine will have a peak torque output rpm 2-500 rpm LOWER than the peak HP output rpm. WHY.. Because you clutch for peak HP.. NOT peak Torque..
So, when your engine is heavily loaded and it begins to drop a few hundred rpms.. It will fall into its PEAK Torque realm and have a much easier time at recovering and returning back to peak HP rpms... Hence, the reason for having the engine' speak torque rpms lower than its peak HP rpms.. Without this relationship.. the engine would be VERY hard to clutch in a full load situation. Make sense?
When people talk about engines, they like to quote and cite peak HP numbers..For example.. RK Tek 860R makes 180HP at 8300 rpms. Peak torque is closer to 7900/8000 rpms.. OK, so, those are the peak numbers.. What MANY fail to realize is that the area under the torque curve is what really makes one engine stand out over another.
Different engines builds build TORQUE at different rates.. Some build torque rather rapidly and then hold the torque across a very wide rpm band.. This is a good engine and one that will accelerate very hard and will be very easy to clutch.. The area under this torque curve would look like a bumpy straight line with very little upward slope.
Some engine builds do not build torque quite as fast but can get to the same torque numbers as another engine.. This engine's torque curve will look like a side of a mountain.. So, while the 2 engines can make roughly the same torque and HP, their torque curve can look completely different. So, the area under the curve really tells you how the engine will "perform" under real-world operation.
In flat land racing, this curve is not so important (note: I did NOT say NOT important. just not as
).. because you come out of the gate and immediately hit the desired rpms and stay there for the duration of the race. so, what the curve looks like BELOW the rpms you are running are inconsequential.Now, boon docking and mountain riding.. Different story.. It is very common to have your engine quickly lose rpms because you are on and off the throttle. So, the flatness of the torque curve becomes a big player..
This is where the Big Bores really shine... I will speak to my BB, because it is , obviously, the one I know the most about...
The 860R builds torque at a very rapid rate when compared to the stock engine. It builds it faster and builds much more of it.. So, you have a very broad and very flat torque curve.. So, when on and off the throttle OR when your sled hits a super "Deep" spot and drops some rpms.. The BB is MUCH less effected and can recover much faster than the stock engine.. WHY?? Much more TORQUE AND HP at ALL rpms.... Simple as that.. Where the stock engine will get overloaded.. the Big Bore will be much less effected by it and continue to pull...
The RKT 860R has massive torque and HP increases in the 6500-8000 rpm band. So, it has a much easier time handling anything "HIGH LOAD" situation it encounters. This becomes very apparent when banging a steep hill with 3ft of fresh and deep powder.. There is no comparison between the Big Bore and the stock engine.
Kelsey
@ 4000 rpm what do you feel Torque or HP ? I agree with Poet Brew HP is just a #.
OT
OT
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Kelsey, run a 12:1 head on the big bore and what do you have ? Not Much....Run a 14:1 head on the same big bore and than you have increased Torque/HP....At the end of the day good clutching brings out the Torque/HP
OT
OT
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Neither.....it hasn't engaged the clutch yet. Can't fool a poet!
Not true Poet Brew, Your choice if primary spring determines engagement, 4000 rpm is what i engage at.
OT
Read your own post OT. The way you stated it you asked him the question. So therefore Brew is correct in that he feels nothing at 4000 rpm's and your clutch engagement rpm is of no relevance in the question to him. Poet still not fooled and undefeated
Read your own post OT. The way you stated it you asked him the question. So therefore Brew is correct in that he feels nothing at 4000 rpm's and your clutch engagement rpm is of no relevance in the question to him. Poet still not fooled and undefeated
It'a pretty clear that you don't understand the relevance.....A well tuned & clutched 800R from the moment you stab the throttle "ENGAGEMENT" should have alot of "TORQUE"....If you don't feel the "TORQUE" every time you stab the throttle at 'ENGAGEMENT" you might want to have you 800R looked at because it's very likely your 800R has a few issues.
OT
It'a pretty clear that you don't understand the relevance.....A well tuned & clutched 800R from the moment you stab the throttle "ENGAGEMENT" should have alot of "TORQUE"....If you don't feel the "TORQUE" every time you stab the throttle at 'ENGAGEMENT" you might want to have you 800R looked at because it's very likely your 800R has a few issues.
OT
I totally agree!!
the gains of the torque in a BB compared to a stocker is essential... @ engagement....
Boost @ idle for the turbojunkies also.I totally agree!!
the gains of the torque in a BB compared to a stocker is essential... @ engagement....
So is this why you have a BB for this year? lol
What can't show the math.........
151 HP Stocker
@1000' = 146 HP
@2000' = 142 HP
@3000' = 137 HP
@4000' = 133 HP
@5000' = 129 HP
@6000' = 125 HP
@7000' = 122 HP
@8000' = 118 HP
@9000' = 114 HP
173 HP Big Bore
@1000' = 167 HP
@2000' = 162 HP
@3000' = 157 HP
@4000' = 153 HP
@5000' = 148 HP
@6000' = 144 HP
@7000' = 139 HP
@8000' = 135 HP
@9000' = 131 HP
At 9000' the BB has approx. 12.5% more power in optimun conditions " Hard Pack or Trail conditions..... IMHO, a 12.5 HP gain in chest deep snow isn't anything to be proud of
This was calculated at @3% and rounded off... Depending on the atmosphere/temps/conditions @ 9000' you can easily expect even MORE HP than posted with an SHR860R.
OT
This is like shooting fish in a barrel...
To make it fair...since the new 800's make 150 hp...lets go back a couple years...2006 to be exact, 800HO REV Summit (140 hp) vs a 2006 600HO SDI Summit (125 hp)...theres your 15 hp difference...do YOU really want people to believe what your saying or just stop while your miles behind??-BJ
BTW- when I DOO my 860R for a mountain guy he gets an altitude specific head...and a stock motor has a low elevation pump gas head...so my 860R power is HIGHER at 9000' than your math shows...but what do I know....LOL
Great statement Kelsey - this is hitting the nail on the head. Cumulative torque #'s are what we are after.
It'a pretty clear that you don't understand the relevance.....A well tuned & clutched 800R from the moment you stab the throttle "ENGAGEMENT" should have alot of "TORQUE"....If you don't feel the "TORQUE" every time you stab the throttle at 'ENGAGEMENT" you might want to have you 800R looked at because it's very likely your 800R has a few issues.
OT
I think you are confusing "torque" and "torque multiplication". Torque is what the engine generates, torque multiplication is what your clutching and chaincase do. I can make a 500 feel like it has more "torque" than your 800, just by gearing it really low (granted it will hit top speed at 25 mph..
).HP is just a combination of two factors - torque and RPM (as already stated), so don't get too hung up on HP #'s. When you alter the RPM that torque is made at, you alter the HP. For rotating object the HP calc is: (Torque X Speed in rpm)/5252
So....an 800 with 110 ft/lbs at 7500 rpm = 157 HP. Now bump that 110 ft/lbs up to 8500 rpm and you get 178 HP. 21 "HP" gain just by moving the torque curve (which is why HP is just a math game). This is why having a broad torque curve is so essential in a sled, this ensures the most efficient clutching possible. Typically a BB with more torque is going to stay above the stock torque curve longer, which means your cumulative torque is far greater than stock (and therefore the theoretical math does not work). More efficient clutching means less heat and more efficient power transfer, another advantage to the BB. BB's and larger torque curves are also more forgiving on clutch set ups, so you could be off by a gram or two and may not even know it, whereas you might notice it more with the stock power curve.
While you may think that 12.5% at 9000 ft in waist deep snow isn't worth it, the reality of the situation is that the gains are likely far greater than our SW mathematics.
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