Hayden chain tensioner
Seasoned HDF Member
Joined: Nov 2010
Posts: 17,548
Likes: 7,199
From: Oxford, Nc
If they slapped the cover, you'd hear it. That sound is unmistakable. And if they slapped the cover, Hayden wouldn't be selling them now for going on 15 years.
Mine has been in there for 12 years now, and I've been in the primary a couple of times to replace stators. When the tensioner is installed, you get about 5/8" play, that's it. The primary chain is taut, (not tight,) and the double springs hold it there. There's no evidence of my chain ever touching the case.
When I hit 100,000 miles on it, I contacted Hayden before a road trip and asked them what needed replaced. They said the springs probably never, ( the shoe goes 300,000,) but if I did replace them, I had to get them from Hayden because they're not the kind of spring available at a hardware store. I believe them.
IMO, the M-6 is undoubtedly one of the best additions I've made to my last 3 bikes.
Novice
Joined: Jul 2011
Posts: 22
Likes: 0
From: Iraq for 5 yrs, now Afghanistan
Looks like I'll be jumping on the bandwagon as well. I've been looking at these for the last couple of months and it sounds like a good way to go. I need to stop reading forums...even though these make good sense...all the good sense items take a chunk outta the money tree. 
I should add a little more detail to my experience. I was being a bit harsh in my evaluation of any reduction in "clunk" when going from neutral to 1st. I never really expected a "click" into gear from neutral since that has everything to do with the clutch plates sticking or dragging when the bike is first started up from an overnight rest. There is no getting away from that. However, the whirring noise from the primary chain (not the noise related to a failed/failing IPB) is completely gone! Or at least cannot be heard over my pipes! And I would have to say that shifting gears is a bit softer and less "clunky" feeling and sounding. All in all. I got exactly what I wanted from the install. Peace of mind that the primary chain cannot overtighten and a quieter primary! Well worth the price of admission!
Seasoned HDF Member
Joined: Nov 2010
Posts: 17,548
Likes: 7,199
From: Oxford, Nc
I don't know. I've got about 85 hp but I don't use it much...just a gentle touring rider. (That's why everything's lasted 120,000 miles so far. 
)
Give Hayden a call, I think her name was Cathy ( easy tp talk to,) and ask before you commmit.
)Give Hayden a call, I think her name was Cathy ( easy tp talk to,) and ask before you commmit.
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Supporter
Joined: Aug 2008
Posts: 5,189
Likes: 16
From: N.E. Wisconsin
According to the parts manual, the double row angular bearing #37906-60 (equivalent to industry #5207) located inside the clutch basket 37813-06A is built as a lateral positioning device more than a radial load bearing. It is designed to accommodate a slight misalignment with the hub assembly when all clutch disks are set free. I would worry more about it's limited operating temperature (250-300°F) than the tension of the chain itself.
If you use an online oil viscosity calculator for bearings (typ. SKF) you will obtain the required viscosity at a given temperature under normal load of the IPB.
At 150 Deg Celsius the 5207 calls for a viscosity ~8 [mm^2/sec] (HTHS)
At 100C it's ~15
At 40C it's ~150*
*edit= (150 is the equivalent viscosity at 40C meaning a grade 40-50 oil will still be efficient when reaching 150C)
From these values you can evaluate your driving habits and see where you stand. Formula+ is perfect for people "in the middle" of a sample, like you and me [today]
At 150 Deg Celsius the 5207 calls for a viscosity ~8 [mm^2/sec] (HTHS)
At 100C it's ~15
At 40C it's ~150*
*edit= (150 is the equivalent viscosity at 40C meaning a grade 40-50 oil will still be efficient when reaching 150C)
From these values you can evaluate your driving habits and see where you stand. Formula+ is perfect for people "in the middle" of a sample, like you and me [today]
Road Master
Joined: Jun 2010
Posts: 1,221
Likes: 4
From: Annemasse (border of Geneva-Switzerland) facing Mt-Blanc.
Once in position, the tensioner can no longer retract nor release the chain, so angular play between crankshaft and gearbox becomes restricted like in a gear drive.
The topic (argument) concerning elimination of the primary chain wear/elongation is a bit 'on the edge' because by design the compensator ramps will over-stretch/whiplash the chain as soon as the Belleville spring washers weaken. The chain must give-in (absorb all the energy) when it is instantly solicited and cannot use its own reserve of elasticity provided by its sag.
Chain wear means the pitch of several links increased/elongated under excessive tension; at this stage its preferable to hear the chain slide against the aluminum housing rather than being left stranded in silence.
For peace of mind I will change my tensioner because I hate to stress mechanical elements; I don't care about performance, I just want to reach destination in the most pleasant conditions and see young children drag their parents close to the bike 'just to see it'
Last edited by Expat1; Nov 28, 2012 at 02:06 AM.