Secondary Clutch/8DN made easy

Not a recent purchase, but I would imagine you can buy it from Bender still, BDS1 is the part number
 
TD Max said:
I think what he's saying is that the drawing is elementary belt deflection setup or belt deflection for dummies. It is only a quick visual part of the proper and thorough way to set it up and assumes that the belt length and c to c are perfect. Good enough to get it out the door and down the trail and to satisfy 99% of the people, but a true racer or HP junkie seldom stops there.


I seem to recall Kerrdog setting his up like this (bolts out and visibly correct) but having more actual deflection than he wanted.
Click to expand...
I added the washers as stingray719 post tells you too and it was better but not what I wanted to see,so I had Allen machine the secondary and now it's good to go,not everyone will need to do this,I just wanted to kill 2 birds with one stone,coil bind and belt deflection,and as a side note I'm just doing the belt deflection by feel and how it rides in the clutch and if the sled wants to creep or the track wants to roll while it's off the ground,might not be proper for some but has always worked for me
 
I just machined mine to be able to use the 8dn belt and made the spring pocket a bit deeper. This way I'll still be able to adjust it for belt wear and the spring binding should be eliminated.
 
nherbst454 said:
I just machined mine to be able to use the 8dn belt and made the spring pocket a bit deeper. This way I'll still be able to adjust it for belt wear and the spring binding should be eliminated.
Click to expand...

Agreed, I now have a helix with the spring pocket machined out to eliminate coil bind.
 
Sorry, not intending to hijack anything here, but I am amazed at the shop manuals (both SkiDoo and Yamaha) that ignore the belt deflection - or slack if you prefer - on the clutch setup. I recently bought a '15 Vector and was shocked when I had the engine running and lifted the rear of the sled and the track started rolling. Did the deflection test and had about 3/4 in. Pulled the secondary, removed one of the two washers on each of the three bolts (I think it was SRXspec a bunch of posts ago) and now it is fine (1.5 inch-ish). The track shouldn't move until the primary engages (low 3000's). If it moves before clutch engagement there is something wrong.

I am amazed that doing a belt evaluation more manufacturers should have a) check width. b) check deflection c) check height in secondary. Keeping in mind that the height in the secondary is in part a measure of belt width. My old SkiDoo SDI (REV platform) had a really easy adjustment built into the secondary, but they also ignored the deflection (I think - I'll have to check my book). They focused on the height in the secondary. Frankly, I am thinking it should almost be a warning that if the track rolls when the sled is at idle and the track in the air that this is dangerous.

Anyway, when I looked closer at the belt (8DN - 34.1mm) the innermost part of the belt cogs has been riding on the central post of the primary sheave. That's where the pull comes from.

I also noticed it didn't like shifting in/out of reverse. I am thing that the constant tension has something to do with it.

belt2.jpg


You can see how the inner cord has been worn off. Probably going to shorten my belt life.

Sorry to any maintenance purist that might be out there, I'm still going to use it. 8^)

Rob
 
Wobbie said:
Sorry, not intending to hijack anything here, but I am amazed at the shop manuals (both SkiDoo and Yamaha) that ignore the belt deflection - or slack if you prefer - on the clutch setup. I recently bought a '15 Vector and was shocked when I had the engine running and lifted the rear of the sled and the track started rolling. Did the deflection test and had about 3/4 in. Pulled the secondary, removed one of the two washers on each of the three bolts (I think it was SRXspec a bunch of posts ago) and now it is fine (1.5 inch-ish). The track shouldn't move until the primary engages (low 3000's). If it moves before clutch engagement there is something wrong.

I am amazed that doing a belt evaluation more manufacturers should have a) check width. b) check deflection c) check height in secondary. Keeping in mind that the height in the secondary is in part a measure of belt width. My old SkiDoo SDI (REV platform) had a really easy adjustment built into the secondary, but they also ignored the deflection (I think - I'll have to check my book). They focused on the height in the secondary. Frankly, I am thinking it should almost be a warning that if the track rolls when the sled is at idle and the track in the air that this is dangerous.

Anyway, when I looked closer at the belt (8DN - 34.1mm) the innermost part of the belt cogs has been riding on the central post of the primary sheave. That's where the pull comes from.

I also noticed it didn't like shifting in/out of reverse. I am thing that the constant tension has something to do with it.

View attachment 150995

You can see how the inner cord has been worn off. Probably going to shorten my belt life.

Sorry to any maintenance purist that might be out there, I'm still going to use it. 8^)

Rob
Click to expand...


My friend had the same issue with the track rotation when lifted on a jack at idle. He was also having vibration at 40mph. Changed belt and issue went away. Stock belt. Old belt looked fine. Only 4k miles on sled, all trail 137" 2016 LE.
 
Wobbie said:
Sorry, not intending to hijack anything here, but I am amazed at the shop manuals (both SkiDoo and Yamaha) that ignore the belt deflection - or slack if you prefer - on the clutch setup. I recently bought a '15 Vector and was shocked when I had the engine running and lifted the rear of the sled and the track started rolling. Did the deflection test and had about 3/4 in. Pulled the secondary, removed one of the two washers on each of the three bolts (I think it was SRXspec a bunch of posts ago) and now it is fine (1.5 inch-ish). The track shouldn't move until the primary engages (low 3000's). If it moves before clutch engagement there is something wrong.

I am amazed that doing a belt evaluation more manufacturers should have a) check width. b) check deflection c) check height in secondary. Keeping in mind that the height in the secondary is in part a measure of belt width. My old SkiDoo SDI (REV platform) had a really easy adjustment built into the secondary, but they also ignored the deflection (I think - I'll have to check my book). They focused on the height in the secondary. Frankly, I am thinking it should almost be a warning that if the track rolls when the sled is at idle and the track in the air that this is dangerous.

Anyway, when I looked closer at the belt (8DN - 34.1mm) the innermost part of the belt cogs has been riding on the central post of the primary sheave. That's where the pull comes from.

I also noticed it didn't like shifting in/out of reverse. I am thing that the constant tension has something to do with it.

View attachment 150995

You can see how the inner cord has been worn off. Probably going to shorten my belt life.

Sorry to any maintenance purist that might be out there, I'm still going to use it. 8^)

Rob
Click to expand...


This is what happens when someone tells someone else that the belt should be above the secondary sheave. Clearly shows the inside wear from the belt being way too tight of belt deflection.

**** Don not believe everything that is posted on social media unless you know the background of that person and what they have tested and proven**** Always go by manufacturer's spec. and if the track turns or tries to creep at idle....the belt is too tight....period.
 
Should also be noted that the tips wear down on the belt adjusting bolts. Either buy new bolts or adjust with washers accordingly.
For example, if the tip of the bolt was worn 1mm, then simply remove the stock 1mm washer. I usually zip tie them on the sled somewhere noticeable.
 
Thought for sure bender racing closed fellas
 
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