Clutch offset question

[Hammer70]

Having to machine the clutch to get it to the full spec range that Yamaha calls for is an assembly issue if you ask me. Some sleds can achieve this and some can't.

My sled stock when measured was at 60.3 mm no shims from factory. I machined 3.5 mm off the back to the bushing. And set up with custom shims and Hurricane tool now it’s bang on and 0 float

 

[Hammer70]

We all know what it is....Please support Dave and buy a bar, its a great tool to have in your box.

Giving out the measurement on a public forum, which would be easily searchable on google is just not right IMO.

Dan

I totally agree it’s a great tool used on three sleds now I will be doing a fourth. you should buy the tool and support Dave.

 

[1nc 2000]

Just got in from plowing. We got another 6 inches of snow today. Can't wait till hunting season is over and trails open up.

 

[DTR 82-27]

I simply asked what the offset was when comparing the Hurricane method to the Yamaha method out of curiosity. As long as the clutch castings are the same the finished offset should be the same from sled to sled. The only difference will be how much machining or shims to get the correct measurement. If no one wants to say because they think I should buy the tool, just say so. I have absolutely no problem spending the $120 or whatever the hell it is. I have already spent several thousand dollars over the last 12 years supporting vendors on this site and I am sure I will spend a lot more in the future. It a little insulting to suggest otherwise.

 

[cannondale27]

I simply asked what the offset was when comparing the Hurricane method to the Yamaha method out of curiosity. As long as the clutch castings are the same the finished offset should be the same from sled to sled. The only difference will be how much machining or shims to get the correct measurement. If no one wants to say because they think I should buy the tool, just say so. I have absolutely no problem spending the $120 or whatever the hell it is. I have already spent several thousand dollars over the last 12 years supporting vendors on this site and I am sure I will spend a lot more in the future. It a little insulting to suggest otherwise.

They did say. 55-58.5 MM. Is range I see.

 

[1nc 2000]

The Hurricane tool measures at the centerline of the primary clutch.
The Yamaha method measures at the aft end of the inner clutch sheave.
If your parallel is off, the Yamaha way of measuring will be off.
That's a very good reason the numbers vary measuring off the two different methods.

Which one would you think would be more accurate?

It's not about the number that your asking for.

 

[Fast]

My sled stock when measured was at 60.3 mm no shims from factory. I machined 3.5 mm off the back to the bushing. And set up with custom shims and Hurricane tool now it’s bang on and 0 float

 

[cannondale27]

The Hurricane tool measures at the centerline of the primary clutch.
The Yamaha method measures at the aft end of the inner clutch sheave.
If your parallel is off, the Yamaha way of measuring will be off.
That's a very good reason the numbers vary measuring off the two different methods.

Which one would you think would be more accurate?

It's not about the number that your asking for.

Parallel will effect both measurement ways no way around it.

 

[1nc 2000]

Parallel will effect both measurement ways no way around it.

I agree. Just saying that the numbers would be different and which one would give the closer measurement to the 1:1 ratio.
Be like Dan, check your Parallel also.

 

[cannondale27]

I agree. Just saying that the numbers would be different and which one would give the closer measurement to the 1:1 ratio.
Be like Dan, check your Parallel also.

That depends on a lot of factors such as belt used. I do know the further out measurement is taken the more accurate it would be at center.

 

[1nc 2000]

Anyway I was talking about the offfset number that people are asking for.
It appears that number is not the same for everybody.
That's why not all of us are giving out the number.
I just don't want to snap any more belts in half. With a tuned up sled it's gets to be a pretty violent explosion when a belt snaps. Prior to using the Hurricane tool I had my side panel blown off last winter from a snapped belt. I am lucky the panel didn't take me off my sled at 90 mph when it hit me.
That is why I say buy the tool and set up your offset that way.

 

[DTR 82-27]

Parallel will effect both measurement ways no way around it.

You are right Cannondale. To check parallel you need four points of reference, two on each plane (or clutch). Both methods discussed use three points of reference.
The Hurricane method will give offset across the secondary to the center line of the primary. I understand being at 1 to 1 certainly helps a lot to have the correct offset. I would assume this is with the width of a new 8JP belt. The Yamaha method will give offset across the primary to the front edge of the secondary only.
To get both parallel and offset you need a long enough straight edge to go past both clutches. With the straight edge against one of the clutches, say the primary, you can measure both the front and back sides of the secondary. This will show both parallel and offset. It’s the same method used by all the old clutch alignment tools.
The big question is what the correct offset should be. By playing around a little with a straight edge, measuring tape and a belt it would not be hard the figure out.
The correct offset measurement will be the same - it’s just the machining or shims needed to get there changes from sled to sled.
What we need is an old school clutch alignment tool like in the pic below but for a Sidewinder. It could check offset and parallel at the same time.

 

[cannondale27]

You are right Cannondale. To check parallel you need four points of reference, two on each plane (or clutch). Both methods discussed use three points of reference.
The Hurricane method will give offset across the secondary to the center line of the primary. I understand being at 1 to 1 certainly helps a lot to have the correct offset. I would assume this is with the width of a new 8JP belt. The Yamaha method will give offset across the primary to the front edge of the secondary only.
To get both parallel and offset you need a long enough straight edge to go past both clutches. With the straight edge against one of the clutches, say the primary, you can measure both the front and back sides of the secondary. This will show both parallel and offset. It’s the same method used by all the old clutch alignment tools.
The big question is what the correct offset should be. By playing around a little with a straight edge, measuring tape and a belt it would not be hard the figure out.
The correct offset measurement will be the same - it’s just the machining or shims needed to get there changes from sled to sled.
What we need is an old school clutch alignment tool like in the pic below but for a Sidewinder. It could check offset and parallel at the same time.
View attachment 143065

Actually Yamaha method does do both and uses 4 points since straightedge goes across back of both clutches but if everyone says parallel is correct it wouldn't matter. I know mine was last year. Yes would like to see a tool like you show for new clutches. I believe Ulmer sells the current one. Maybe he could get a redesign.

 

[cannondale27]

Never mind. Sidewinder is missing spec 2 and 3. What are they thinking? Easy enough to figure out unless they don't want Winder parallel?

 

[snow_rider]

All,

Finally checked my bone stock, never ridden yet, 18 LTX, and it was .050 out with Hurricane Tool...

Gonna have .150 taken off shaft, more then I need, but want to still use washers as required to bring it back in.

I'd love to be a fly on the wall if Dave and the Yamaha engineer that figured out their spec ever had a discussion!