Stinger needs to add his, which will change the whole Bell curve I think.

If he doesn't, I think that I can

Add to the chart:

Freeway, synthetic oil and easy does it riding.

Replaced chain at 12,000 miles, tensioner at 18mm. I had used only MC 10/40 or 20/40 to that point. Bought new & broke in mostly by the book. Some highway miles, ridden to MY ability. I didnt baby it. I didnt just try to blow it up, either. The chain has another 5 or 6 thousand miles in it ( IF the amount of stretch can be extrapolated & the wear calculated),


but the whole tensioner system working (Failing?)together allows the spring loaded adjuster to extend to the max allowable long before the chain is used up.. Crappy design..

Filling in the blanks:

Type of Oil?  syn
Rider type? agressive moderate newb etc?  mod
where do you ride the most (freeways, highways, around town, etc.) local

'96, mileage at failure 21,000 miles, frequent oil and filter changes 1500-3000 miles depending on use, various automotive rated synthetic oil since 4000 miles when I bought it used, 1 PO . Spring loaded tensioner tensioner unit was almost apart and aluminmum housing worn out of round at the top to 3 o'clock looking at the open end. Miles from dropping on the main drive gear. Bike is loaded with faring and wide hard bags and heavy rider but tend to ride in the lower RPM ranges rather than the high I don't wind it to the misfire point before shifting and like a thumper sound so will be close to lugging around town under light load. Did not measure chain replaced it and the spring loaded tensioner, assumed the chain had worn the pins and plates that much. Guides appeared to be unworn. I did replace the crank chain gear as I fractured it using an air impact wrench set the wrong direction on disassembly. Noise was the clue and the first posting of concerns on this site prompted opening her up for inspection as the valve adjustment was OK. Performance was OK still. Max

Table updated  

Dr_Jim's observation sounds reasonable.  A single cylinder with just two cam lobes certainly cycles the cam chain between slack and tension more than a multi-cylinder engine where the tension is more even and constant.  My Ducati single had a gear driven OHC with a "hunting" mesh pattern - that way the same teeth don't line up every cycle so the wear is spread more evenly.  My impression is our 'Zooks chain is loaded by valve spring pressure unevenly so the chain has these tight (worn) spots.  One check might be the pin-to-pin measurement in several places around the chain.  Is the wear (stretch) evenly distributed - anyone done this?