Actually the Pirelli has a pretty stiff carcass, stiff enough to ride on if it's flat, or so they say. That's why it's DOT approved and rated a little less grippy and flexy than other trials tires.

But, I think I may have a solution to the original question as to how to take up that little extra slack. Turns out the pin that the adjuster rests on screws out. I think the thread is 10mm X 1.25. SO an allen head cap bolt with a bigger head diameter than the stock pin ought to thread right in. I'm going to stop by Ace hardware and see what they have.

 

Just flip the adjuster. Personally I hate the motocross style adjusters, the nuts are always striping.

 

Now how would that work? Isn't the distance from the center of the axle to the farthest part on the cam going to be the same whether it's on one way or flipped over? But I tried it and it still didn't move the wheel all the way back.

But this did. That's a 10 X 1.25 bolt with 3 washers under it. What I really need is a 25-30 mm allen head bolt. Could only find 10 X 1.50 at the local hardware store.

 

OMG!...that's a hideous, rube goldberg setup if I've ever seen one!

Pretty creative, actually. It should work fine. My only negative thought that I mentioned before is how that axle is starting to get into the "stepped-down" section of the swingarm. I think that portion of the swingarm is just there to retain the safety pin. The further back you go, the more you get into it. Hey...it will probably not be an issue, but I'd keep an eye out for any stress there.

 

Yeah, I see what you mean - there is a less meat at the tail end of the swingarm. And with the axle all the way back it is lined right up with where it starts to neck down. That could be why the adjusters are the way they are, eh? Oh well, it only cost a few buck to try it out.

Rube Goldberg, huh? Well, I never . . .

 

Well, there she be - a 110 chain on a 13/47 sprocket combination, plus the "Guido Mod" chain adjuster modification. I maybe have a notch or two to take up slack when the chain stretches, maybe.