The original design of the factory Buell tensioner is a fixed item... And, although, Eric worked out the maths and it works well for about 95% if its travel it did not allow any flexibility for the usual road debris found in the UK and elsewhere.... especially if you like the "odd bit of off roading".
So the Free Spirits idea was to make the tensioner wheel sprung loaded... Now while they did a fair job in making it look nice and sturdy... there's a couple of design flaws that Eric's original did not have....
The worst one of these is that it, unless you set it up very carefully, it fouls the exhaust... The lower inside section rubs against the rear exhaust bracket and exhaust itself... Not good.... and the other problem is that the pivot sucks..... a split bush, just in the center section and a shaft that is 40mm long (unit is 50mm wide) that has a countersunk Allen screw, very lightly tightened, each end does not make for a safe secure pivot..... loctite is the order of the day to stop them unwinding...
Oh yes... its sold as a "maintenance free" item...... moving parts... aluminium rubbing against aluminium.... road crap, water and salt.. I don't think its anywhere near "maintenance free".... if fact it seizes up quite nicely thank you.... frequently....
So my plan was to modify my nice new one (the old one has done way to many miles and is a bit knackered to say the least) it to an idea I had... Now as much as I like the look of the "upgrade" kit you can get from Maz at the "Buell Emporium"... to me it still had one fault.... you cannot, easily, tell if it needs a strip and clean or starting to seize because its needs to be oiled more often..
So my plan was not to have a pin that was "fixed" in the outer plates and only rotates in the inner section bush....
My design was to ream out the outer pieces to take the same bush as the centre..... make a shaft/pivot pin that was wider than the tensioner and knurl it to aid rotation...
Will put some photos of it fitted on here in a few days to show how it looks fitted...... The back end is a bit long only so that there was room for adjustments or alternative ways of retention...
The above photo shows nicely the PTFE washers... the pin and end washer are stainless... What I should have done is taken a photo of it disassembled as the bearing part of the shaft is spiral grooved to aid in lubrication and the side plates have been recessed just enough to allow fitting "O" rings to help keep the grease/oil in and the dirt out....
The whole thing is being kept in place by an "E" clip at the moment.... if it works OK it will stay that way.... but if its not secure enough then I can always switch to another option..
The PTFE washers are also a trial as should give a long life but he also machines various types of Nylon/Nylatron etc
Also have a plan to turn up a cover plate which will push it to cover the grease nipple (Its designed to accept a standard grease gun nozzle into the recess)....
I like the look as is but I'm sure many would want a cover...
So all I have to do is rotate the shaft before riding/ monthly..... and if it does not rotate smoothly.... grease it..... if its stuck.. strip n clean time....
The plan now is to see if anybody else would like one....
As I no longer have access to a decent lathe (after being in engineering for a couple of decades I do miss the access to equipment) the whole thing was made by Probitts Engineering out of Finbows Yard, near Bacton in Suffolk..
His mainstay is in high quality parts for all sizes of model trains, but he makes far more than that.
And the good thing is that if enough people want one he will run off a batch....
Message me If you want any more info.. but the plan plan... is to give him my old unit to have a total rethink on the idea of "how to hold the wheel"... I like the idea of a "gull wing" rear piece to eliminate the rubbing/wear issue as a "just change one piece option"..... Or maybe a totally new design that loses the "travel limiting roll pin" by extending the rose joint thread (female rose joint and correct length Allen bolt?) through the back of the center section, which would also make fitting and removal MUCH easier.
Have fun out there....
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