This might help:Still not sure that I understand what black john was talking about
Radial distance to the center of mass (COM)
http://www.sledgear.com/images/figure4.jpg
If you shim the movable sheave away from the spider in the primary clutch (or adjust it with an external adjuster) it increases the contact angle between the roller and the weight. Un-tucking the weight applies additional force on the belt at the lower shift ratios, however, doing so reduces force at the end of the shift curve, which, in most cases, is fine because the weights are generating more than enough centrifugal force at the end of the shift curve.
http://www.sledgear.com/images/figure6.jpg
From articles:
http://www.sledgear.com/TRAtech.htm
http://www.sledgear.com/driventech.htm
craze1cars
VIP Member
Thanks Hammer....that does help. I sort of figured he might be talking about the primary which is what threw me off, since I was inquiring about the secondary adjuster. It appears he was referring to the fact that he doesn't care for the 911 adjuster on the primary then...but his comments should have no bearing on the simple secondary Goodwin deflection adjuster I'm thinking of running with the otherwise stock clutching, right?
I may get deeper into clutching my Attak later, but since I haven't even ridden this sled yet, I have no baseline to gauge any clutching changes against yet. But with belt deflection and clutch alignment being clutching 101, I want to make sure I know how to do both as easily as possible on this Yami. Other changes will come after break-in and some riding, when I see what RPMS I'm turning in different riding circumstances and how flat this thing shifts....once I experience those things for a baseline to tune against, I'll likely be back with more questions on specific clutching issues maybe mid-winter.
Thanks again to everyone, my mind is all caught up now...
On a very related note, especially from those of you who may have dyno'd these sleds, what is the max RPM HP on the stock Genesis 150 FI motor (Apex/Attak)? What does Yamaha publish, and what have others of you found in testing/tuning? If these motors are like most, there will be two different answers....and are the stock tachs pretty accurate? That will help me decide where clutching might need to be after I get a chance to ride. I saw one link here where Supertuner did a stock dyno run and found the peak to be at 10,400. Is this about right or have others seen different numbers?
I may get deeper into clutching my Attak later, but since I haven't even ridden this sled yet, I have no baseline to gauge any clutching changes against yet. But with belt deflection and clutch alignment being clutching 101, I want to make sure I know how to do both as easily as possible on this Yami. Other changes will come after break-in and some riding, when I see what RPMS I'm turning in different riding circumstances and how flat this thing shifts....once I experience those things for a baseline to tune against, I'll likely be back with more questions on specific clutching issues maybe mid-winter.
Thanks again to everyone, my mind is all caught up now...
On a very related note, especially from those of you who may have dyno'd these sleds, what is the max RPM HP on the stock Genesis 150 FI motor (Apex/Attak)? What does Yamaha publish, and what have others of you found in testing/tuning? If these motors are like most, there will be two different answers....and are the stock tachs pretty accurate? That will help me decide where clutching might need to be after I get a chance to ride. I saw one link here where Supertuner did a stock dyno run and found the peak to be at 10,400. Is this about right or have others seen different numbers?
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Test 1: 150.7 hp @ 10,500
Test 2: 148.4 hp @ 10,700
Test 3: 149.8 hp @ 10,600
Clutching most sleds from 10,500 to 10,800 has shown good results. I have seen some tachs off as much as 300 rpm on top end.
Test 2: 148.4 hp @ 10,700
Test 3: 149.8 hp @ 10,600
Clutching most sleds from 10,500 to 10,800 has shown good results. I have seen some tachs off as much as 300 rpm on top end.
craze1cars
VIP Member
Exactly what I was looking for SRX. Thanks a bunch.
apex yooper
Expert
Sorry I couldn't answer sooner. You have been given correct info, but I disagree with one point. It doesn't have to be spot on. Close is good enough. If it had to be spot on, Floating secondarys would not be used. When you nail it, the offset will change, with free float, until you get off the throttle.
Then it will realign.
Then it will realign.
craze1cars
VIP Member
Funny this topic popped back to the top on it's own today. I actually installed this Goodwin adjuster today. This is one SLICK little product! Now I have INFINITE belt deflection adjustments that take about 30 seconds to do without any disassembly, and I'm not tied into washers and bolts. Very cool, easy to install, and by the time you add up all the OEM shims, spacers, washers, and bolts that are REMOVED and NOT replaced to install this piece, the rotating mass of all the leftovers is more than the Goodwin adjuster itself! So it even reduces total rotating mass (I actually weighed it...weight loss is all of about 15 grams...so that oughta gain me about 10 mph top speed right?! ).
And any of you Doo fans who love the little belt-changing tool that every Doo since the mid 80s has had in the toolbox, now my Yami has one too! Instead of busting knuckles and getting all dirty with belt dust to manually shove the secondary sheave open, I can just turn the little knob with the tool and the sheave is held partially open while belts are changed. Of course that throws your deflection adjustment out the window, but a little scratch mark on the adjuster can solve that if you have a bit of forethought. Besides, if you're changing belts, it's time for a deflection adjustment anyway, right? Another 10 seconds trailside and you're good to go...
Yamaha should make this thing standard, IMO. All for only $29.95 plus shipping. You'd think I work for Goodwin, eh? I don't.
But I have to add one thing which has brought me a little confusion. Goodwin disagrees with this link with regards to shimming out the secondary:
http://www.totallyamaha.com/snowmobiles ... hAlign.htm
According to that link, I should be adding 4 to 8 thous worth of shims behind the secondary to get proper fixed clutch alignment. Goodwin disagrees and says I should NOT add these shims. They say Yamaha aligns their clutches for proper offset with the fixed half of the floating clutch pressed tight against the inner shims. Their adjuster holds it in the same position. This means I still have proper clutch alignment even though my secondary is now fixed in position. They say adding the 4 to 8 thous worth of shims will bring the clutch OUT of alignment, and their adjuster does NOTHING that would effect clutch alignment, so no such adjustment or shimming is necessary.
So do I believe the info from the link, or do I believe Goodwin? Both are reputable. Seeing as how I don't have an alignment tool yet I can't really effectively check clucth alignment myself. Curious what others of you might think on that topic.
And if admins want to move this whole topic over to the new "Engine and Clutching" section, feel free.
Thanks!
And any of you Doo fans who love the little belt-changing tool that every Doo since the mid 80s has had in the toolbox, now my Yami has one too! Instead of busting knuckles and getting all dirty with belt dust to manually shove the secondary sheave open, I can just turn the little knob with the tool and the sheave is held partially open while belts are changed. Of course that throws your deflection adjustment out the window, but a little scratch mark on the adjuster can solve that if you have a bit of forethought. Besides, if you're changing belts, it's time for a deflection adjustment anyway, right? Another 10 seconds trailside and you're good to go...
Yamaha should make this thing standard, IMO. All for only $29.95 plus shipping. You'd think I work for Goodwin, eh? I don't.
But I have to add one thing which has brought me a little confusion. Goodwin disagrees with this link with regards to shimming out the secondary:
http://www.totallyamaha.com/snowmobiles ... hAlign.htm
According to that link, I should be adding 4 to 8 thous worth of shims behind the secondary to get proper fixed clutch alignment. Goodwin disagrees and says I should NOT add these shims. They say Yamaha aligns their clutches for proper offset with the fixed half of the floating clutch pressed tight against the inner shims. Their adjuster holds it in the same position. This means I still have proper clutch alignment even though my secondary is now fixed in position. They say adding the 4 to 8 thous worth of shims will bring the clutch OUT of alignment, and their adjuster does NOTHING that would effect clutch alignment, so no such adjustment or shimming is necessary.
So do I believe the info from the link, or do I believe Goodwin? Both are reputable. Seeing as how I don't have an alignment tool yet I can't really effectively check clucth alignment myself. Curious what others of you might think on that topic.
And if admins want to move this whole topic over to the new "Engine and Clutching" section, feel free.
Thanks!