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Old Man Mountain P-clamp rack mounting hardware
$6.00
These clamps are are used to attach luggage racks to bike frames that don’t have brazed-on or built-in attachment points on the frame’s seatstays. The clamps are shaped like the letter “P”, wrap around each seatstay, and provide solid mounting points to bolt the top of a luggage rack to your bike.
The listed sizes refer to the diameter of the seatstay, measured across the width of the seatstay tube. Tube diameter is a hard thing to measure without proper tools—it is easier to figure out the circumference (distance around) the stay, using a cloth ruler or piece of string, then converting that measurement to the diameter. Here is a table to do the conversion for you:
| If the tube circumference is | use this p-clamp size |
| 2.0” or less | 5/8” |
| 2.4” or less | 3/4” |
| 3.1” or less | 1” |
| 3.9” or less | 1-1/4” |
| 4.7” or less | 1-1/2” |
| 5.1” or less | 1-5/8” |
If your seatstays are on the border between two p-clamp sizes, get the larger clamps and make shims using tape or old inner tubes to build up the diameter of the stays a bit.
These clamps are made by Old Man Mountain, but work with any brand of rack that bolts to the frame seatstays.
| Specifications | |
|---|---|
| Our part numbers | 8176138 5/8" pair
7513644 3/4" pair 7158760 1" pair 5829639 1-1/4" pair 7966956 1-1/2" pair 7934340 1-5/8" pair |