Belt Deflection, Floating Secondary

[BlueByYou2000]

Can't help ya there...maybe someone with the Maxximum adjuster will chime in. Or just try to put it on and see how it fits? I would have to assume that their spacer would replace the stock spacer. Can't really hurt anything by seeing how it fits

Just for fun and on the same topic, there's further info about fixed secondarys in here. . http://www.totallyamaha.com/ if you go to the Tech pages/Snowmobile tech/Clutches and jetting/RX1 clutch alignment fixed or floating.

It covers how to do it and why. I don't necessarily agree with all of the statements in there...like the engine doesn't torque because it's rigidly mounted, that's a bunch of bull and I promise you there's some twisting and clutch alignment changes going on under there when you hit it. I also disagree with the usual need to add a couple shims behind the secondary when you lock it...because my alignment bar was spot on with NO shims behind the secondary. But I am in favor of fixing it, because I primarily believe that the "floating secondary" thing is sort of a myth. Sure you can slide it back and forth on the shaft when there's no tension on it, but when 150 horses grab onto that sucker I am very certain that the clutch locks itself onto the shaft in whatever position it happens to be in at the moment, and it is NOT going to slide around until you get completely off the throttle and probably not until you totally stop moving. If it was sliding back and forth on that shaft at high tension, we'd all be occasionally replacing our wearing jackshafts and the holes in the spacers of the secondary would slowly oblongate. But that's not happening, so the clutch basically IS already fixed from the every moment they've engaged and started pulling. The problem lies in the question of whether the clutch just happened to be in the right "floating" position at that particular moment of launch and lockdown. Maybe it was, maybe it wasn't. If it's floating around maybe while coasting or immediately when they disengage, you will never know. But if you manually lock your secondary into the correct position based on proper alignment, it is ALWAYS in the correct position when the torque grabs it at moment of engagement.

So that's my train of thought, and why I've been locking my secondaries on all floating setups since about the mid-80's. It just gives more consistent clutch alignment/performance and belt wear. But this is my first Yami in that entire timeframe, so I can't say yet with total confidence that locking is best for THIS sled. But it appears a few others here seem to think so...

Over and out.

I wrote that article when the RX-1s came out. The part you say BS to the motor being solid mount, it is more solidly mounted than any 2 stroke before its time. No traditional rubber motor mounts. Its as rigid as you are going to get besides welding the motor to the chassis. Will it flex, yes, but nothing like a 2 stroke. You can also add an engine tensioner to help with any motor flex you may encounter...BBY

 

[BlueByYou2000]

The reason you may or may not have to add shims behind the secondary is because if your not locked at 15mm offset, then your not in allignment. Ive done many many Yamahas, and have added as little as .20 and as much as .80 behind the secondary to achieve a 15mm offset...BBY

 

[craze1cars]

Thanks Blue. No offense taken I hope, as it is an excellent article. I just REALLY nitpicked that twisting engine thing. I fully agree and understand what you mean about these sleds not having rubber mounts and they'll flex MUCH less than the old-school rubber mounted 2 strokes. But as you said, our rigid mounted motors still flex some (mostly due to chassis flex, and not engine mount flex) unless you add a tensioner to control it.

As for the 15mm offset, about all I can tell you is that I did my 2007 with a proper Yamaha alignment bar that's designed to set it at a 15 mm offset, and I had to add zero shims to get it dead on.

Here's my other reasoning on that adding shims deal: Yamaha recommends when measuring offset on their floating clutches, the secondary should be pushed tight to the inside before you take your measurement, right? This would represent the locked clutch position if you were to simply lock the clutch down via your written procedure without even bothering to add any shims behind. So.....assuming the clutch was properly at 15 mm offset prior to locking the secondary, it will STILL be at 15 mm offset after you lock it down without adding shims behind.

So it stands to reason that on all those Yamahas you locked, every single one of them must have been around 12 to 14 mm offset before you did your procedure. Because if they were correctly at 15 mm to start with, there would be no need to change the backside shims. Maybe Yamaha's newer sleds are coming out of the factory with better clutch alignment than the old RX-1's did? Just a guess...but since you wrote the article, I'm assuming you've also done this to the new Apex in your avitar. So I dunno.

I'm honestly not trying to second guess your experiences at all, as obviously you know what you had to do on those sleds to get them set up, but is my logic missing something here? Thanks!

 

[BADSLED]

"BBY" Do you still recommend running a torque arm to keep the engine in alignment or is the flexing to minimal?

 

[black john]

moter mount,s

these moter,s are still rubber mounted. and there are many differnt side,s to clutching. the reson,s for the floating are when the moter is under load it torqe,s the moter over slitly then when you go to a cruse this back,s the torqe off and moves,s thing,s around a little then there,s the back shift under power wich moves the center again and finely the back shift to the stop postion. it,s my humble opion that locking down the secoundary should not be locked down based on this . and if you have your primary and secoundary modded for o/d there even more movement in the off set . so locking down the secoundery would work fine for drag raceing but i dont think it work,s that good for the avarge rider when you are on and off the gas countless time,s during a ride. 15 mm - or + 1 mm . plus this sould make up for small amount,s of paralizum being out as there are two justment,s for this as well (right reat-left front)

 

[Black 1000]

I completely agree with the above statement.

 

[iasledder]

Why did Ski Doo and Polaris drop the "Free-Float?
Just a question, I don't know the reason. I doubt that it was a cost issue.

 

[craze1cars]

It seems that for this, like for all tuning tricks, there are many opinions...so everyone just has to decide for themselves. That's what makes experimenting/tuning so much fun IMO. Everyone has the right answer. And yet every answer is different.

What most intrigues me is that there is now disagreement here between two very reputable and experienced members on this site about a simple fact. The article written by BBY says thes sleds have a "solid mounted engine". But Blackjohn states this is a "rubber mounted" engine. There is no grey area here...so which is it guys?

This first Yamaha of mine hasn't been apart far enough for me to know the answer for myself, and I have no desire to disassmble it again just for fun, but I am very interested in knowing. Thanks!

 

[Soldier'spapa]

yep.....when i "fixed" my secondary with Oring...I had to remove all shims from BEHIND secondary,and lock it in there...which yielded the proper 15mm OFFSET from BACK of rear sheave on primary to BACK of rear sheave on secondary....using straight 3/8 barstock...simple,easy to do procedure...the yamaha spec is 15mm + or - 1.5mm,so it does give you some leeway to put a thin shim behind if yours isnt at 15 aleady

dan

Just so I get this correct the first time .... Is the 15mm measurement made with both halves of the secondary fully closed (Both halves touching each other, prior to making changes to achieve proper deflection ) or after deflection is set (Halves slightly apart from each other)

With 1 thin washer in place behing the secondary (Fully closed) I am at 15.17mm. after setting the deflection by opening up the secondary a bit, the offset reduces to 13.9mm. Soud about right??

 

[BlueByYou2000]

Re: moter mount,s

these moter,s are still rubber mounted. and there are many differnt side,s to clutching. the reson,s for the floating are when the moter is under load it torqe,s the moter over slitly then when you go to a cruse this back,s the torqe off and moves,s thing,s around a little then there,s the back shift under power wich moves the center again and finely the back shift to the stop postion. it,s my humble opion that locking down the secoundary should not be locked down based on this . and if you have your primary and secoundary modded for o/d there even more movement in the off set . so locking down the secoundery would work fine for drag raceing but i dont think it work,s that good for the avarge rider when you are on and off the gas countless time,s during a ride. 15 mm - or + 1 mm . plus this sould make up for small amount,s of paralizum being out as there are two justment,s for this as well (right reat-left front)

Black John

Here is how the motors are mounted. http://www.ronniesmailorder.com/fiche/m ... &year=2006

click on frame, then motor bracket.

 

[BlueByYou2000]

Thanks Blue. No offense taken I hope, as it is an excellent article. I just REALLY nitpicked that twisting engine thing. I fully agree and understand what you mean about these sleds not having rubber mounts and they'll flex MUCH less than the old-school rubber mounted 2 strokes. But as you said, our rigid mounted motors still flex some (mostly due to chassis flex, and not engine mount flex) unless you add a tensioner to control it.

As for the 15mm offset, about all I can tell you is that I did my 2007 with a proper Yamaha alignment bar that's designed to set it at a 15 mm offset, and I had to add zero shims to get it dead on.

Here's my other reasoning on that adding shims deal: Yamaha recommends when measuring offset on their floating clutches, the secondary should be pushed tight to the inside before you take your measurement, right? This would represent the locked clutch position if you were to simply lock the clutch down via your written procedure without even bothering to add any shims behind. So.....assuming the clutch was properly at 15 mm offset prior to locking the secondary, it will STILL be at 15 mm offset after you lock it down without adding shims behind.

So it stands to reason that on all those Yamahas you locked, every single one of them must have been around 12 to 14 mm offset before you did your procedure. Because if they were correctly at 15 mm to start with, there would be no need to change the backside shims. Maybe Yamaha's newer sleds are coming out of the factory with better clutch alignment than the old RX-1's did? Just a guess...but since you wrote the article, I'm assuming you've also done this to the new Apex in your avitar. So I dunno.

I'm honestly not trying to second guess your experiences at all, as obviously you know what you had to do on those sleds to get them set up, but is my logic missing something here? Thanks!

The RX-1s I locked were all different...BBY

 

[BlueByYou2000]

"BBY" Do you still recommend running a torque arm to keep the engine in alignment or is the flexing to minimal?

Not necessarily. My RTX is not locked down, my belt life and performance has been just great leaving the factory float. My RX-1 on the other hand was a different story...BBY

 

[Srxspec]

Matt, they are all rubber mounted, they just don't allow as much movement as some of the previous 2-strokes. Click on Engine, then on Crankcase and you will see Item # 3 is the rubber mount.

 

[BlueByYou2000]

Why did Ski Doo and Polaris drop the "Free-Float?
Just a question, I don't know the reason. I doubt that it was a cost issue.

And dont forget Cat. I brought this up in a letter to "Dear Ralph" at Snowtech which got published. He agreed that locking it down and doing it correctly will result in better results.

Bottom line here, everyone has there opinions on this. This is a very health converstaion and guys like Black John has prooven it is not necessary to lock your secondary and still produce good results. We go round and round every year on this site on this subject matter. If you want to lock it, then do so, if you dont then dont. End of story. My RX-1 liked it, my RTX likes it floating...BBY

 

[BlueByYou2000]

Matt, they are all rubber mounted, they just don't allow as much movement as some of the previous 2-strokes. Click on Engine, then on Crankcase and you will see Item # 3 is the rubber mount.

Allen, Yamaha told us in Minocqua that the mount system was considered a rigid mount. Ive had item #3 out and its nothing like a traditional rubber motor mount on a 2 stroke. The thickness of the compressed rubber is mininal in comparison to most 2 stroke mounts. So I guess technically, the thin rubber makes it a flexible system, but no where near a 2 stroke. Thanks for finding that pic. I appreciate it...BBY