Maintenance and Repair Tips

Instructions For Adjusting Sturmey Archer 3 Speed Gear Transmission

Symptons: If gears are skipping a gear adjustment will in most cases cure the problem. Sturmey Archer and the German SRAM gear systems used by Brompton are very durable and generally trouble free when used over many years of normal riding. However, ALL TYPES OF GEARING MUST NOT BE RIDDEN OUT OF ADJUSTMENT. Doing so may cause damage to gear components and cause the hub to malfunction.

Adjusting STURMEY ARCHER 3 speed gears:

With Brompton UNFOLDED follow gear shifting cable to point of entry into rear wheel. Here you will find a small chain and rod assembly attached to the cable end where it is attached with a screw in barrel fitting secured by small knurled lock nut. Loosen lock nut (gently use two pairs of pliers if necessary) and disassemble cable from indicator chain assembly.

Now ensure that chain and rod assembly is screwed into hub completely. Turn back maximum of half a turn if necessary to ensure sure chain runs freely through round shouldered indicator nut on wheel axle and reattach indicator chain to cable assembly.

Select second gear on the handle bar gear control. Looking through the “window” in the right had axle nut turn the barrel nut cable adjuster until the end of the indicator rod as attached to indicator chain is exactly even with the end of the axle. Note: The indicator rod is attached to end of shifting chain. Now spin rear wheel with pedal crank and reexamine to assure proper adjustment. Finally tighten lock nut against barrel nut.

If attention to the above does not enable all 3 gears to be obtained, please contact your bicycle shop for assistance.

Instructions for Adjusting Sturmey Archer 5 Speed Gear Transmission

Symptons: If gears are skipping a gear adjustment will in most cases cures the problem. Sturmey Archer and the German SRAM gear systems used by Brompton are very durable and generally trouble free over many years of normal use. However, ALL TYPES OF GEARING MUST NOT BE RIDDEN OUT OF ADJUSTMENT. Doing so may cause damage to gear components and cause the hub to malfunction.

Adjusting STURMEY ARCHER 5 speed gears.

  1. With Brompton UNFOLDED follow gear shifting cable to point of entry into rear wheel. Here you will find a small chain and shifting rod assembly attached to the cable end with a screw-in barrel fitting secured by small knurled lock nut. Loosen lock nut (gently use two pairs of pliers if necessary) and disassemble cable from indicator chain assembly.
  2. Ensure all components are properly fitted to the right side of axle and that when the axle nut is properly tightened the axle protrudes no more than 2.5mmfron the nut. Ensure that the support washer is at 90 degrees (correct to 90 degrees if necessary) and that the selector guide is correctly located on the support washer.
  3. Ensure that the gear selector chain and shifting rod is fully screwed into the axle Gear Selector Key inside the rear hub. Turn back a maximum of half a turn to line up with the selector guide system.
  4. Select 5th gear on the handle bar gear control and connect the cable connector until half way down the indicator coupling and tighten lock nut.
  5. Select SECOND GEAR on the gear control and rotate the pedal crank forward to ensure the proper gear is engaged. Turn the adjuster at end of cable at rear wheel until the center of red (or blue) mark at the end of indicator rod is level with end of axle.
  6. Retighten lock nut to lock the adjuster.
  7. Select 5th gear, rotate the pedal crank, change back to SECOND GEAR and check adjustment.

Instructions For Adjusting SRAM 3 Speed Gear Transmission

Symptons: If gears are skipping a gear adjustment will in most cases cures the problem. Sturmey Archer and the German SRAM gear systems used by Brompton are very durable and generally trouble free over many years of normal use. However, ALL TYPES OF GEARING MUST NOT BE RIDDEN OUT OF ADJUSTMENT. Doing so may cause damage to gear components and cause the hub to malfunction.

  1. Place the handlebar shifter in gear position “3”. Move the crank to check that the gear is engaged.
  2. To make the adjustment, the cable must be taut in third gear to be able to transfer a shift movement directly to the hub.
  3. Push the plastic locating sleeve onto the small pull rod until the cable is taut. Make sure you do not pull the indicator chain out of hub. Cable should be taut but not so taut as to cause any part of shifting chain to move out of hub.
  4. To CHECK: Place shifter in gear position “ 1” while moving the crank.
  5. Setting too loose: In gear position “1” the tension chain can be pulled out of the deflection nut on hub by hand.
  6. Setting too tight: It is difficult to place the shift lever in gear position “1”.
  7. If required, readjust the shift mechanism (in third gear).

The Definitive Brompton Tire Change Manual

by Charles Shapiro

OPEN MANUAL

This guide is intended for people who have never fixed a flat on the rear tire of a bicycle, or who are intimidated by the complicated-looking fixtures on the rear wheel of a Brompton folding bicycle. With the help of this text and the pictures beneath the links in it, you should be able to remove the rear wheel from your Brompton, disassemble the tire and inner-tube, patch or replace the tube, and put the whole thing back together to make the bike 'good as new'. Expect to take an hour or so the first time; I do this about once a month, and it typically takes me close to 30 minutes.