Bike Forums - View Single Post - Longer stem and reach

11-23-16 | 09:53 PM

#4

FBinNY

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Joined: Apr 2009

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From: New Rochelle, NY

Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter

It depends on the stem's rise angle* (if any) Extending a horizontal stem extends the reach by the same amount. But if the stem rises or drops, you have to multiply the added length by the cosine of the rise angle to get the change in reach.

For those who prefer to let the magic of computers handle the math, there are various calculators on line. Here's one.

* rise angle is the net angle from the horizontal based on how the stem and head tube angle add/subtract. Ie. a 73° head tube and 17° (90-73) stem will produce a rise angle of 0 or 34° depending on whether the stem is angled up or down.

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Last edited by FBinNY; 11-23-16 at 10:07 PM.

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