Originally Posted by
Leisesturm
Abused is really the right word for this drivetrain. I'm not sure it has enough miles to significantly wear chainrings. On many bikes chainrings are a lifetime installment. But these chainrings show evidence of numerous shifts under load. If that's you doing that ... you should stop. If you bought it like that from a previous owner ... eef, I wouldn't have. Not sure why the new triple needs so much longer a BB spindle. Can you double check that? But, as another poster noted, as long as the new crank isn't a unit triple with bolted together rings, then you can just move them over to your existing crank-arms. As for chain wear. Before you write off the LBS's BS, is it possible that they may be onto something? TBH I've never used a chainwear indicator in anger. When things start skipping is usually what I wait for. How many miles are on the drivetrain? No wear at all is just as suspect as so much wear that the odometer is coming around to zero again ...
He bought it new and rode the hell out of it every season for 20+ years.
He only replaced what broke and I don't know when if it ever saw the shop.
The new (to me) triple/cranks that are on the way are used but in very good condition.
It's the same model that's on it now so they use the same BB.
My original BB was a UN52, I installed a NOS UN55 that's regarded as a mild upgrade but same 73/110mm configuration.
Different spindle lengths are to line up different cranks/rings with the bike's frame geometry to keep a straight chainline right?
The set on Jungle website in my OP was just an idea.
I was considering swapping the rings but after a good look I'm in for replacing with better condition cranks as well.
I don't know where you got the idea that I checked the chain in anger lol.
The shop checked it and I checked it when I got my own indicator tool. None of us were angry
Can a chain stretch so much that a chainlength indicator tries to fit between the next set of links?
That's what LBS suspected. That the chain was worn a half inch over it's length. Doesn't seem possible.
All conjecture's moot at this point. New and near new complete drivetrain is on the way.
I know that everything I don't have to replace makes for better value but I like the bike and if it's 75% new by the time it's reliable that's OK. When I rode back in the 90's I replaced/upgraded everything on my Rockadile over time. The only thing original on it was the frame. At least if that happens again it's a helluva good frame.