PD: Primary Drive Alton sprocket

[Oldhaven]

Has anyone used a standard metal sprocket long term on a twin Alton? I just returned from a nice end of season ride with my ammeter showing -2, so checked the Alton drive sprocket and found this:

I have heard that the standard PD15 can damage the middle row of the primary chain, which would certainly cause more damage than a few nylon shavings, but this failure was after less than a thousand miles. I thought I had checked the tooth engagement carefully, but perhaps I had it too tight. the Alton still turns, though with its characteristic notchiness, so I don't believe it is at fault.

Ron

 

[bmetcalf]

The standard steel sprocket is all I have used since at least 1999. Do use a good locking method for the screws that hold it on the Alton hub, if it falls off, the chain will suffer. DAMHIK

 

[Michael Vane-Hunt]

I have used the steel sprocket on my twin with a McDougalator which is probably harder on the primary chain rollers than an Alton. I did shed all the center rollers but John McDougal showed me I was running the primary much too loose. Since this episode, which fortunately caused no damage besides the chain and dyno sprocket, I keep my primary much tighter and check the tension every 1000 mlies or so, every second or third day when riding to Minnesota this year. I have put about 8000 miles on this year and several thousand last year with no damage to the chain rollers and upon inspection this week the dyno sprocket shows no wear at all. I intend on removing the primary this winter and check for stretch. Will change if needed, a new chain is cheaper than a catastrophic failure some where in the middle of nowhere.

 

[roy the mechanic]

I have had the steel sprocket for around 4 years, it has had no issues.

 

[Oldhaven]

Well, that's good news. Thanks all. Saves me a bit of change too since I have a good steel sprocket. I will pay attention to mesh depth and primary chain tension. Reliable power generation is necessary since I have coil ignition.

 

[vincenttwin]

I trashed two of the white plastic gears , one because primary was a little loose and the other who knows , now running steel

 

[Albervin]

When I pulled my newly acquired Shadow to pieces last month the plastic Alton sprocket was fit for the tip. Why is it fitted in the first place?

 

[Vincent Brake]

Here is what i do, as the magnets are extreeeeemly strong killing all things "fixed"
Set it axially with about 1 mm play (stnrd plastic is a tad to wide) and set the alton a bit to right side (check when lifting the clutch as your PD20 big sprocket moves right axially ). at least i tought so, or was it left
Radial: i see to it that it has 0,3-0,5mm (measure with a round pin beaten to 0,5 mm)

oh and i locktite the inner hub screw

 

[Little Honda]

View attachment 17872 Here is what i do, as the magnets are extreeeeemly strong killing all things "fixed"
Set it axially with about 1 mm play (stnrd plastic is a tad to wide) and set the alton a bit to right side (check when lifting the clutch as your PD20 big sprocket moves right axially ). at least i tought so, or was it left
Radial: i see to it that it has 0,3-0,5mm (measure with a round pin beaten to 0,5 mm)

oh and i locktite the inner hub screw

Use the Hegeler dyno/ignition unit in place of magneto and you will have forgotten the name of its builder after 5 years. Your triplex chain will
have a better life.

 

[vibrac]

Its a pity Mr Hegeler hasn't got as good a website as a product
Hegeler dyno/ignition unit http://www.vinsparesgermany.com/ is not working