How to Change to 7 inch arm on a Schwinn Phantom

[Harvie]

I got a Phantom and wanted to lower the gear ratio and increase the leverage of the crank. Wald has aftermarket stuff but it DOES NOT FIT CORRECTLY. You must use all Schwinn Stuff and follow this or you will end up with no hair, anywhere......

Get Dog Leg Schwinn crank 7 inch long made pre war and until 48
Get or have pristine Schwinn cups races and bearings (whole BB set) USE SCHWINN BEARINGS ONLY
Choose wether you want 1/2 or 1 inch pitch.

IF using a 1 inch skip tooth sproket measure and compare to new 1/2 sproket, if .180-.190 thicker assemble and good to go no spacing needed. If one of the newer 1 inch thin repos see below.

IF using 1/2 inch pitch, the sproket is going to be .175 too thin to tighten up on the crank. so get or make a 3/16 spacer (valve spring shims work well and come in a zillion sizes) put the sproket on the crank put the spacer on and install the inner race. assemble the rest as usual.

Trying to use Wald cups /BB kits the crank will not space out enough, trying to use thicker spacer to make Wald stuf to work you will not get the lock ring on the other side.

Try asking the clowns selling you the stuff and they say o heck yea my stuff will do the job.....but try returning it when it does not work and you hear :lol: :lol: just before your phone line goes dead... :mrgreen:

 

[Anonymous]

Is 6 1/2" long enough?

I just checked my '70's Schwinn Varsity crank for ya.

On the cheap and easy...

 

[Harvie]

Is 6 1/2" long enough?

I just checked my '70's Schwinn Varsity crank for ya.

On the cheap and easy...

Ok, I give up. What does this have to do with changing to a 7 inch crank?

 

[Anonymous]

SORRY,I was only trying to help ya for crank length reference.

NEXT

 

[GTV]

Good info! I've been thinking about going to a 7" crank on my Typhoon when I swap the kickback and 52t chainwheel in. So it's fairly straightforward? The only thing I'm concerned with is dragging pedals when I'm really "on it"

 

[Bendix]

Good info! I've been thinking about going to a 7" crank on my Typhoon when I swap the kickback and 52t chainwheel in. So it's fairly straightforward? The only thing I'm concerned with is dragging pedals when I'm really "on it"

if original, your typhoon has 28tpi threading on the bb parts. the vast majority of generic, wald, etc, bb sets will be 24tpi.

if it was mine, i'd pick up a used old school cromo sugino 175 or 180mm crank (old school cromo cranks are 28tpi, 175mm is the most common length on modern mountain bikes so most folks are used to it) on ebay and reuse the rest of the original schwinn parts. you can also buy new 28tpi cranks but they're kinda chunky looking on an old bike.

 

[Harvie]

AS to above post: 180mm would be the 7 inch arm AND make sure the pedals are 1/2 and not 9/16.