Apex clutch on Sidewinder

[sideshowBob]

I am going to install a new Apex clutch with no overdrive on my new Sidewinder for a few reasons:

1] The Apex clutch has set screws on roller pins to help keep it a little quieter.

2] The Sidewinder 10% overdrive clutch creates a belt speed of 9700 RPM at full shift and engine RPM of 8800,
as a comparison, an Apex with stock clutching and engine RPM of 10800 only has a belt speed of 8800 RPM.
A belt speed of 9700 for any length of time destroys belts, even 8DNs, lower belt speed is one reason you can run an Apex wide open for miles with no belt issues. The 850 Ski Doos have a 15-17% overdrive and also are very hard on belts, even with their lower engine rpm.

3] Higher belt speeds create excessive heat and rob horsepower

4] Apex primary clutches have been proven to be very durable and reliable in boosted sleds well in excess of 300hp, so they are the perfect clutch for our Sidewinders

5] Lastly...I have 20+ years of collecting springs, weights, tools, spare clutches and parts for these Yamaha primaries so I have motivation to keep using them

I will be installing the Apex primary with NO overdrive, floating the secondary, and just gearing my sled up to regain my top speed while maintaining no more then a 1:1 shift ratio just like I have been doing on all my Yamaha sleds for decades.

JM.02c

 

[02ViperMody44]

Been contemplating getting into a SW myself, and had been hearing about doing this mod, with a 911 cover for some belt "durability". But you would NOT overdrive the primary for the reasons stated above? Did have it done on my Apex, but that is a completely different animal. Never really though about the belt speeds going up from the O/D

 

[sideshowBob]

I have always used the 911 cover on my Yamaha primaries since they first came out with them and will use one on the SW...in fact I already bought it.
I have tried Over Drive on my previous Yamaha's 2 strokes and the Apex with varying results. because the 998 doesn't have a gear reduction to reduce clutch speeds, like a VMAX4 or Apex, I will stay away from an overdrive mod on my Winder. [even a stock Apex primary will over drive slightly]

JM.02c

 

[DMCTurbo]

I am going to install a new Apex clutch with no overdrive on my new Sidewinder for a few reasons:

1] The Apex clutch has set screws on roller pins to help keep it a little quieter.

2] The Sidewinder 10% overdrive clutch creates a belt speed of 9700 RPM at full shift and engine RPM of 8800,
as a comparison, an Apex with stock clutching and engine RPM of 10800 only has a belt speed of 8800 RPM.
A belt speed of 9700 for any length of time destroys belts, even 8DNs, lower belt speed is one reason you can run an Apex wide open for miles with no belt issues. The 850 Ski Doos have a 15-17% overdrive and also are very hard on belts, even with their lower engine rpm.

3] Higher belt speeds create excessive heat and rob horsepower

4] Apex primary clutches have been proven to be very durable and reliable in boosted sleds well in excess of 300hp, so they are the perfect clutch for our Sidewinders

5] Lastly...I have 20+ years of collecting springs, weights, tools, spare clutches and parts for these Yamaha primaries so I have motivation to keep using them

I will be installing the Apex primary with NO overdrive, floating the secondary, and just gearing my sled up to regain my top speed while maintaining no more then a 1:1 shift ratio just like I have been doing on all my Yamaha sleds for decades.

JM.02c

I’m a big believer in maintaining 1:1 as well.

 

[sideshowBob]

I’m a big believer in maintaining 1:1 as well.

Are you really Olav Aaen ?

 

[PowderFalcon]

I’m a big believer in maintaining 1:1 as well.

When you say 1:1 do you mean clutch alignment?

 

[sideshowBob]

1:1 shift ratio means that when the clutches are shifting out that they stop when both clutches are running the belt at the same diameter so the primary clutch and the secondary clutches are turning at exactly the same RPM.
Overdrive is when the primary clutch reaches a diameter larger then the secondary clutch so now the secondary clutch and jackshaft are spinning faster then the primary clutch, this increases belt speed and also loses efficiency.

 

[PowderFalcon]

1:1 shift ratio means that when the clutches are shifting out that they stop when both clutches are running the belt at the same diameter so the primary clutch and the secondary clutches are turning at exactly the same RPM.
Overdrive is when the primary clutch reaches a diameter larger then the secondary clutch so now the secondary clutch and jackshaft are spinning faster then the primary clutch, this increases belt speed and also loses efficiency.

Thanks Bob!! Makes sense

 

[DMCTurbo]

Are you really Olav Aaen ?

Not sure what your trying to say...

 

[DMCTurbo]

When you say 1:1 do you mean clutch alignment?

What he said lol

 

[sideshowBob]

Not sure what your trying to say...

Just kidding you...Olav Aaen clutching book is the Bible on clutching. One of the big messages from his book is 1:1 is the best formula for speed.

 

[DMCTurbo]

Just kidding you...Olav Aaen clutching book is the Bible on clutching. One of the big messages from his book is 1:1 is the best formula for speed.

Ok... yes I know I’ve read his clutching book 100 times lol.

 

[KnappAttack]

When I measure where the belt runs on a stock RX-1 clutch vs. a stock Sidewinder clutch, they are equal, so both will have the same amount of overdrive. Not sure why the rumor is floating around that the Winder clutch has more O.D.

I take that back, I remember now early on Yamaha claimed in their marketing that the Sidewinder belt was going to have a different angle on it along with different angles on the primary for more O.D. but its easy to see that never panned out to be true.

 

[Mototown]

From the 2017 update book with all the new sidewinder changes

 

[sideshowBob]

When I measure where the belt runs on a stock RX-1 clutch vs. a stock Sidewinder clutch, they are equal, so both will have the same amount of overdrive. Not sure why the rumor is floating around that the Winder clutch has more O.D.

I take that back, I remember now early on Yamaha claimed in their marketing that the Sidewinder belt was going to have a different angle on it along with different angles on the primary for more O.D. but its easy to see that never panned out to be true.

Interesting

Yes I was going on the info that the Sidewinder has more overdrive...I still am going to install an Apex primary though as I know exactly what I am dealing with.