Roadmaster bicycles are some of the most affordable bicycles on the market. Their super-low price makes for a great bang-for-your-buck value, but unfortunately means that the parts on the bike that take care of shifting and braking, such as shifters, derailleurs, brakes, and levers go out of adjustment relatively easily. Learn how to fix your Roadmaster bike at home, using household tools, and save money and time instead of taking your bike to the local bike shop.
Spin the cranks of the bike forward and shift both the front and rear derailleurs into the smallest cog possible using the shifters on the downtube.
Loosen the front and rear derailleur cable stop bolts (where the cable is clamped to the derailleur) using a 10mm wrench. Spin the cranks of the bike forward a few revolutions to settle the derailleurs.
Observe the alignment of the small cog, chain, and derailleur pulleys from behind the bicycle. The chain should form a straight, vertical line between the cog and pulley. If the pulley pulls the chain to the right, tighten the high-limit screw using a Phillips screwdriver. If it pulls the cog to the left, loosen the high-limit screw.
Pull the rear derailleur cable taut underneath the rear derailleur cable stop. Tighten the cable stop bolt using a 10mm wrench to hold the cable in place.
Lean over the top of the bike and look straight down at the front derailleur. Take notice of the alignment of the chain inside the derailleur cage. If the chain rubs on the side of the cage closest to the seat tube, loosen the low-limit screw using a Phillips screwdriver until it sits perfectly between the two sides of the cage. If it rubs on the outside of the cage, tighten the low-limit screw until the chain is aligned.
Pull the front derailleur cable taut underneath the cable stop using a pair of needle nose pliers. Tighten the front derailleur cable stop bolt using a 10mm wrench.
Take the bike out for a test ride and shift through all the gears to be sure everything is now working properly.