Mechanical Stuff Here are a couple of pics from under the hood of the
worlds fastest snowmobile… I was thinking what a great ad it would make to get
Hondo and his
world record mileage sled togther with
G-force and their world speed record sled. I see a simple caption, something to the effect of:
What does the worlds fastest snowmobile have in common with the worlds most reliable snowmobile? Yamaha engines! 
This
supercharged G-Force Apex has a potential of over
500 hp, the view from the cockpit is somewhat
intimidating. The large central tank contains ice water for engine
cooling, the tank on the right side is water used specifically for the liquid-cooled,
inter-cooler, then flows over the exhaust system, exiting via a water jacketed exhaust pipe (makes for a cool looking vapor cloud out the back). Some long travel MTB shocks up front for a comfy inch or two of
suspension, The steering is achieved using cables like an old style
F-I boat… The tank on the left running board hold the fuel (
100% alcohol) and the one you can barely see up front holds the oil. They lost an engine to this at one point due to the extreme acceleration duration which forced the oil into the back of the tank causing the front mount oil pick-up to suck air… doh!
I have seen this fluid
primary clutch before that Gilles is helping bring to the next level. There are
pistons in each of the cylindrical chambers which are oil filled. Under
centrifugal force the pistons force the oil into another chamber through tunable passageways causing the shieve to close. Note the schrader valve: the top of the main chamber uses
air pressure to replace the primary spring to return the shieve, forcing the oil back into the the piston cylinders. It is
infinitely adjustable by varying the amounts of air and oil. It also is not limited (durability) by RPM like a conventional clutch, which in our case, could
negate the need for a
reduction gear. They have developed a very cool feature with a hydraulic, remote control which allows the driver to hold the clutch shift on the line regardless of RPM, can you spell
‘holeshot’… boggles the mind!
I had mentioned that
Gilles has developed a
clutch spec for the
Nytro which in his words is clutched ’similar to a 2-stroke’. Our OE clutch spec is intentional delivering a very hard hit for the purpose of bump
timing and lofting the front end over
obstacles . He has discovered-
for the guys running around on the groomed trails- that lowering the shift RPM, keeping the engine in the
fat part of the torque curve allows for
superior trail manners with increased fuel
economy. He has machined his own fly weights which shift out sooner than stock and keeps the engine working, they have re calibrated the secondary and applied a little
magic, the end result has more than a few Quebec trail burners
smiling.
When Gilles was explaining his tuning
theory for the Nytro, I was reminded of the old ‘wind-shield wiper’
analogy. This is where the tach and speedo
needles advance at the same rate, kinda like a couple of
windshield wipers, as opposed to a narrow power band engine (2-stroke) that ideally should tach out to the optimum max RPM then drag the speedo needle up to speed. I wagged my index fingers to demonstrate and Gilles gave me a big grin…’nough said.
Looking to tame the
beast, putting more power to the trail with no loss to top
performance? Give
Gagne Lessard a call, don’t be shy they have English speaking staff… what I’m hearing is all good! cheers cr
New Stuff My friends over on
Totallyamaha have probably seen the latest
‘teaser’ but in case you don’t know…
Johnny is back (and thank the powers that be… so is
Bunny). I would have posted this sooner but I just stumbled out from the
mushroom patch
The embargo date for the 2010 sleds is
Feb 10 at 12:00 noon EST. We will have all the
specs up on our web-sites and after the dust settles, I’ll add my .25 to the c
ontroversy.Yes you read that correct. I anticipate that we will have controversy after reading all the
conjecture on what we are about to unveil… I do hope the
300hp turbo Apex rumor won’t disappoint too many if it doesn’t happen… ;-) cheers cr
Accueil 
Mer 04 Fév 2009, 17:05