Just wanna see what others prefer ???? Pipe A makes 152 hp at 7600 rpm and pipe B makes the same clutching run at 8000- 8100 rpm. Anyone have any Idea on how much more hp pipe B makes without me dynoing it. Just don't have time and curious what others might have to say ????about trail riding in differnt rpm ranges.....F7 pipes by the way .....
PIPE TESTING
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If you know that pipe "A" was clutched correctly to begin with, you can assume pipe "B" is the better pipe. Be careful, when working with the track dyno (or even field testing), as a better pipe will not always show more rpm or power, if it is not loaded hard enough with the clutches. Pipes are best tested on the engine dyno first.
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If as you say you are using the same clutching the HP was only moved when changing the dynamics of the pipe and the HP is the same in both. I think for trail use a higher reving pipe making the same HP might not be disirable since you will not be in the peak zone the majoirty of the time. In fact I think in most cases you will experience a loss in performance due to this change. It is amazing how little time you spend at WOT on a sled. My Mach Z when hooked up to the computer will tell you exaclty the time spent invarious rpm zones and I was shocked to see under 5% of the time I was at WOT. I would have bet large dollars I was in the WOT rpm zone considerably more than all others except start up. As I discovered and was told by the mechanics midrange rpm zone is by far the majority of time used on a sled.
ptm
ptm
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[/quote]
Would it be accurate to say that if pipe B overeved the clutching that the motor is making more hp ?
What if pipe B made less than A on the dyno but went faster in the field? What would you do?
I encountered this last fall testing the BMP mod . Made more power on the dyno but could not out perform the stock pipe in the field . :dunno:
2 indentical sleds both making the same hp 1 at 7600 and the other at 8000 I think if both were clutched accordingly the 8000 rpm sled would be faster . :dunno:
I would rather have pipe "A" Since HP is a factor off of torque and RPM pipe "A" should make more power to 7600 rpm meaning more torque in the low numbers for trail riding. If you have a pipe that will carry the rpm you could realy have less torque through out and get the same or slightly higher numbers due to the rpm increase. There are many things that go into the performance of the pipe so it may not be an apples to apples comparison..... In a real world low rpm high torque in a trail sled would be my choice. Higher torque would pull taller gears and you would get your speed back......
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IMO I should add that depending on what you are doing with the sled in question - trail or race - that will make the difference in what pipe you will want. IMO the lower reving pipe will have a more suitable power band - HP/torque - for trail riding namely in the midrange rpm zone the majoirty of trail riding is done. I would have to be of the beleif that the higher reving pipe may bring more mph into the equation therefore being better for racing but only real world testing will prove any of this.
ptm
ptm
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Great topic and good reading! :beerchug:
I've found throughout the years that running a stock motor at higher RPM's than designed for(twin pipes) will take many miles off the life of the motor and of course the CVT becomes less efficeint(sp) but doesn't drop dramatically until 8400RPMS.
Just my 02 :div20:
I've found throughout the years that running a stock motor at higher RPM's than designed for(twin pipes) will take many miles off the life of the motor and of course the CVT becomes less efficeint(sp) but doesn't drop dramatically until 8400RPMS.
Just my 02 :div20:
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I have to agree with a lot and disagree with a lot..
on a bike , car etc, with gears, the power band may make a difference.. But on a sled with CVT tranny, it will not IMO. not saying that revving to 10k is good.. but when you are cruising you really have no power on hand, just the cruise power.. so if its within 10hp or tq who cares.. now if you nail it and it quickly jumps up to its desired torque band, then it shouldn't matter what rpm it actually is.. yes a lower rpm helps motor life, usually more low end torque etc.. But you are only seeing this for a split second.. Once up to that rpm.. then the HP starts to take over as it reaches the desired WOT rpm..
So basically, if clutched and geared correctly, they may run side by. I like rpm if its reliable.
on a bike , car etc, with gears, the power band may make a difference.. But on a sled with CVT tranny, it will not IMO. not saying that revving to 10k is good.. but when you are cruising you really have no power on hand, just the cruise power.. so if its within 10hp or tq who cares.. now if you nail it and it quickly jumps up to its desired torque band, then it shouldn't matter what rpm it actually is.. yes a lower rpm helps motor life, usually more low end torque etc.. But you are only seeing this for a split second.. Once up to that rpm.. then the HP starts to take over as it reaches the desired WOT rpm..
So basically, if clutched and geared correctly, they may run side by. I like rpm if its reliable.
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rpm's rule!
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