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[cannondale27]

So part of the old premise behind that wobble bearing design must have been some sort of self alignment gone bad.

Yes they (Cat) originally had motor and jackshaft rigidly mounted together. Still do on some.

 

[ROCKERDAN]

With the old magic bearings on those models, there needed to be more play in chain tension back then. At least that is how my 12 was. So there was more "back off" on adjuster. That was after they realized the "auto tensioner" was a bad idea in conjunction with the axial bearing which would tighten too much,then not be able to loosen once auto tensioned to the next spot.

I would think that with new design, there is no axial bearing anymore I assume, since engine is mounted more solidly now and no more TCL ect....So why not just a normal 1/4 turn back off now? Are they still using old instructions in manual maybe?

Also, wont a 22 tooth top gear help too? Stock is 21.

Dan

 

[Motorhead]

Yes larger diameter top g

With the old magic bearings on those models, there needed to be more play in chain tension back then. At least that is how my 12 was. So there was more "back off" on adjuster. That was after they realized the "auto tensioner" was a bad idea in conjunction with the axial bearing which would tighten too much,then not be able to loosen once auto tensioned to the next spot.

I would think that with new design, there is no axial bearing anymore I assume, since engine is mounted more solidly now and no more TCL ect....So why not just a normal 1/4 turn back off now? Are they still using old instructions in manual maybe?

Also, wont a 22 tooth top gear help too? Stock is 21.

Dan[/QUO

The 22 top should keep the chain away from that casting nub a bit more then the 21.

 

[cannondale27]

With the old magic bearings on those models, there needed to be more play in chain tension back then. At least that is how my 12 was. So there was more "back off" on adjuster. That was after they realized the "auto tensioner" was a bad idea in conjunction with the axial bearing which would tighten too much,then not be able to loosen once auto tensioned to the next spot.

I would think that with new design, there is no axial bearing anymore I assume, since engine is mounted more solidly now and no more TCL ect....So why not just a normal 1/4 turn back off now? Are they still using old instructions in manual maybe?

Also, wont a 22 tooth top gear help too? Stock is 21.

Dan

I have run a 25t top gear in mine for most of its life and it still hit but less than the others. Maybe they never noticed the wear either so kept the same 1.5 turns out even after wobble bearing was ditched. It wouldn't be first time the manual was wrong. Even 2018 Manuals still have a wiring diagram that is unreadable. We have awesome sleds but this aspect of Yamaha has been seriously lacking since this joint Venture. Cat has been much faster responding to issues,publishing legible info and assisting with some issues. Makes me puke a little.

 

[STAIN]

I may just grind this area down before reassembly. Hopefully my track arrives soon.
I ran my Viper chain finger tight for a long time, 5000 miles, before upper bearing failure. In fact I think the failure was linked to a belt explosion under high load, high speed situation. I could tell right away after the belt change that something was different in the drivetrain. My theory is that when the belt blew the chain unloaded and cracked the upper bearing. The bearing failed 50 miles after the belt blew and I could feel it getting progressively worse with each mile after the belt change. And I was 7 hours from home, 4 day trip ruined.

 

[cannondale27]

I may just grind this area down before reassembly. Hopefully my track arrives soon.
I ran my Viper chain finger tight for a long time, 5000 miles, before upper bearing failure. In fact I think the failure was linked to a belt explosion under high load, high speed situation. I could tell right away after the belt change that something was different in the drivetrain. My theory is that when the belt blew the chain unloaded and cracked the upper bearing. The bearing failed 50 miles after the belt blew and I could feel it getting progressively worse with each mile after the belt change. And I was 7 hours from home, 4 day trip ruined.

That makes sense about belt. They can be very violent explosions sometimes! Grindings a option but like I said one of the case mounting screws is in that protrusion. So I think its better to just leave it alone and hope they come out with another new spec for chain tension. Watch oil for sparklies.

 

[ROCKERDAN]

Is there any reason the adjuster should be backed off more then 1/4 turn, like I have done on every sled ever?

I was wondering this when I was reading manual, and thought that was odd and might be old news from magic bearings days..lol

Maybe half a turn, Hard to imagine the chain hitting there if its not too darn loose and slapping.

Dan

 

[cannondale27]

Is there any reason the adjuster should be backed off more then 1/4 turn, like I have done on every sled ever?

I was wondering this when I was reading manual, and thought that was odd and might be old news from magic bearings days..lol

Maybe half a turn, Hard to imagine the chain hitting there if its not too darn loose and slapping.

Dan

Your guess is good as mine other than its kind of a judgment call when someone tells you finger tight. I know some farmers that could unscrew Lug Nuts with their fingers! Oldtensioners did not have the spring. Top of list that's what Yamaha says. Now back in 13 the manuals said finger tight and 1/4 turn out so that's what we all did since we did it all along. Many including me found it was to tight and would whine when decelerating just like if you got a old one tight. Believe I backed it off another 1/4 turn so 1/2 total and rode on. No noise.Was failures of chaincase etc first year. They then put out a bulletin a year later saying 1.5 turns out and its been that way ever since.

 

[Jafo1970]

The grinding on that post is pretty normal. My 2012 with almost 10,000 miles was ground about a 1/3 of the way in and seem to stop then. I've seen it on most machines. I don't like any gear smaller than 22 on top.

 

[jetpilot785]

I ran my chain at 1/4 out from finger tight the first year before the revised specs. They called for the 1.5 turns out. I had the case apart the second year to inspect everything after running it tight the first year and wanted to see the difference in chain flex from the original 1/4 turn to the updated 1.5 and I didn't like what I saw as the chain made contact with the case in a couple of spots just pushing on it with my finger so I ended up after tinkering a little that 3/4 turn out from finger tight was a good sweet spot on the viper and ran it for 8200 miles with no chain, gear or wear issues. I did replace all bearings in the case at around 5500 miles for preventative maintenance and I will tinker again on the sidewinder to see what it will like for tension but you guys are right, when the chain loads and unloads, it has a wave type effect similar to the track and the more slack, the bigger the waves and the more contact the chain makes with the case components.

 

[jetpilot785]

Is there any reason the adjuster should be backed off more then 1/4 turn, like I have done on every sled ever?

I was wondering this when I was reading manual, and thought that was odd and might be old news from magic bearings days..lol

Maybe half a turn, Hard to imagine the chain hitting there if its not too darn loose and slapping.

Dan

I'm going to guess and say that with the way the self aligning bearing works allowing the jackshaft to move a little under loads, the chain tension changes a little and they set them up a little looser to account for that internal movement but with the newer engine mounts being stiffer and them going back to a standard deep groove bearing on top, i wouldn't be surprised if the chain tension goes back closer to the old specs of years past at 1/4 turn out from seated.

 

[sxr70001]

I thought I heard that the extra chain slack was so you would have enough slack for reverse to work properly. I could be wrong though, it's been awhile since we were talking about this back when we had all just gotten our Vipers. I do remember we had a number of chain case failures because the manual was wrong and people were running their chains too tight.

 

[cannondale27]

I ran my chain at 1/4 out from finger tight the first year before the revised specs. They called for the 1.5 turns out. I had the case apart the second year to inspect everything after running it tight the first year and wanted to see the difference in chain flex from the original 1/4 turn to the updated 1.5 and I didn't like what I saw as the chain made contact with the case in a couple of spots just pushing on it with my finger so I ended up after tinkering a little that 3/4 turn out from finger tight was a good sweet spot on the viper and ran it for 8200 miles with no chain, gear or wear issues. I did replace all bearings in the case at around 5500 miles for preventative maintenance and I will tinker again on the sidewinder to see what it will like for tension but you guys are right, when the chain loads and unloads, it has a wave type effect similar to the track and the more slack, the bigger the waves and the more contact the chain makes with the case components.

Thats good info Jet Pilot. Thanks for that.

 

[ROCKERDAN]

Great info here....It very well could be a reverse thing too, so its not to taught.

I think a round "ONE TURN OUT" sounds like a good number.

 

[Dieselxtx]

Great info here....It very well could be a reverse thing too, so its not to taught.

I think a round "ONE TURN OUT" sounds like a good number.

That’s what I’m going to do 1 turn and the key to reverse is not have belt set to high in the secondary so the primary is pulling all the time. I’m pulling my asphalt setup out this week I’ll get pics of mine with 2200miles on it and see how bad it’s worn mines been at 1.5 turns out since new