Originally Posted by
sidcharles
i understand needing the cogs to be parallel with the chainrings and that there is only so much side-to-side latitude the chain can absorb in its travel from low to high cog & chainring combinations.
one of my down the path questions will be if i can change chainring & cog thicknesses to use a barrel link type - maybe "modern" is a better word - chain.
the original chain looks like it could power a mini-bike with a Briggs & Stratton engine.
that must have been when i was in my delirium because i don't remember that. i did measure the existing factory rear dropout inside to inside and came up with 125 mm.
i don't even know what O.L.D. means.
but i can certainly imagine what having the rear wheel off the frame centerline means : Trouble
take some time to look thru this glossary, ok?
https://bike.bikegremlin.com/168/bicycle-glossary/#O
"OLD: Acronym for Over Locknut Distance. Term still used for hub width, although many modern hubs with “industrial” bearings don’t have locknuts. On cup and cone hubs (that used to be the only available in the past), the outer most nuts were used to lock the cones in position by counter-tightening them, so they were called “locknuts”. Explained in this post: Bicycle rear hub."
Locknuts are also known as Jam Nuts, and are typically rather narrow, but can also be a standard nut.
the guy that created the Bike Gremlin site is a member here, btw.
and he needs to complete his Glossary..
PS.. your bike's OLD measurement is actually supposed to be 126mm... 120, 126, 130 and 135 are the most common, STANDARD, rear hub OLDs. Front STANDARD OLD is 100mm, but there are a couple other, very rare, exceptions to that rule.
and THRU AXLE designs are a completely different thing, with their own, still in flux, standards... 110mm front is common... rears are 142, 148, mostly... and no actual locknuts are used.