Chris_in_Miami

Another recent thread in this forum brought up the topic of standardization of the position of mid-fork braze ons as it relates to rack compatibility, and it got me wondering if such a standard existed. I decided to measure the bikes in my garage and found the following measurements (from the center of the mid-fork boss to the center of the rearmost dropout eyelet on the fork) :

1992 Santana Vision 70mm
1987 Schwinn High Sierra 70mm
1989(?) Peugeot Alpin 68mm
1985 Schwinn Voyageur 60mm

I don't believe there is a real standard, but I'm still wondering how broad the range of measurements is. I'd like to hear how other bikes measure up and it may prove useful to have a record of these measurements. Please share your own bike's measurement as described above

seeker333

Check your measurement and/or conversion (25.4mm per inch).

I have 4 forks from 3 manufacturers, 3 measure 165mm, 1 measures 175mm.

I believe 165mm is the accepted standard, and the one used by Tubus, Surly, Civia (QBP brands in general).

rogerstg

1990 Miyata 1000 = 165mm
2009 Windsor Tourst = 160mm (Nashbar low rider rack fits well)
2009? Fantom CX = 165mm

Chris_in_Miami

Yes, I'm off to a great start

1992 Santana Vision - 170mm
1987 Schwinn High Sierra - 170mm
1989(?) Peugeot Alpin - 168mm
1985 Schwinn Voyageur - 160mm

njkayaker

+- 2mm is probably within acceptable tolerances. The 160mm is the only different one.

Keep in mind that the acceptable range in distance numbers would be larger for a horizontal slot than it would be for two holes.

I get 173mm on my Rocky Mountain Sherpa (this might be 1-2mm off).

================

As far as I recall, the Blackburn Lowrider was the first of that kind of rack (it went against convention). It's that rack that motivated putting on the mid-fork eyelets (they didn't exist commonly before the Lowrider). And other manufacturers made their own versions of the Lowrider (presumably, matching the mounting dimentions).

https://www.adventurecycling.org/feat...ack_primer.cfm

Of course, it's possible that some bicycle manufacturers didn't consider the location of the eyelets very carefully.

The end-fork eyelet the Lowrider kinds of racks use (the lower-rear one), is the fender eyelet (the original purpose). The eyelet at the front-top of the fork was the rack eyelet.

Randonneur bikes sometimes have small front racks (for supporting large handle bar bags, etc) and there might be eyelets on the fork for these racks (and the eyelets are higher up on the fork than the lowrider eyelets are located).

Chris_in_Miami

Yes, I was surprised to find that on a well regarded bike from that era. I measured it several times to be sure.

njkayaker

For a rack that has a long-enough horizontal slot for the eyelet, it's the vertical distance that is critical. That is, it's possible that a original Lowrider rack would fit fine on the old Schwinn (1985 is around when the Lowrider was introduced).

Note, too, that increased fork rake or decreased head-tube angle will increase the distance between the two eyelets.

The mid-fork eyelets exist because of the original Lowrider rack.

Jim Kukula

Both my 2010 Thorn Nomad Mk2 and my 1996 Trek 520 measure 165 mm.

thecrunge

My 1998 Cannondale T1000 measures 167mm.