[MENTION=109949]wrk101[/MENTION] I rewrote line 6:

"6. The small chainring should clear the chain stay by about 4 to 5mm, depending on small chainring diameter and any clearance flat on the chainstay.

Every time you remove and replace the crankarm it will seat a little further onto the spindle. Also the crank arm bolts should be re-torqued after 50-100 miles of riding depending on the rider's weight, strength and style of riding. That seats them further onto the spindle too.

If a bike gets used a lot the crank bolts or nuts should be frequently checked to make sure they haven't worked loose. Squeaking or creaking when honking up a hill is a good (bad) sign that the crankarms need to be retightened! Continued riding with that condition will end up trashing the taper in the crankarms. That's why used cranks should be carefully checked for damaged tapers.

The 4-5mm figure is a "WAG" (wild assed guess) but gives wiggle room for future crankarm re-seating on the spindle plus it allows for switching to a larger inner chainring.

Another point, a frame with short chainstays a 130mm rear hub and larger inner chainrings will run out of clearance a lot faster than one with 120mm or 126mm rear dropout spacing and longer chainstays.

If there's not enough clearance or if the crankarm sticks out too far you have to use a different spindle or BB."


[MENTION=109949]wrk101[/MENTION] "At some point, you can get a little flex and the chainring will rub against the chain stay. At that point, you need more clearance."


I'm lazy!

Many years ago I realized the old adage - "Do it right the first time!" was true!

It's a lot easier spending a little extra time and effort than repeatedly redoing a repair!


verktyg

Chas.