How to Make the TTR 125 Taller
by William Machin
Yamaha’s stock TTR 125LV and 125L dirt bikes are preset at 30.5 inches high at the seat, providing approximately 10.4 inches of ground clearance. Riders with longer legs or a lower center of gravity might need more ground clearance for negotiating moguls and when riding in deep grooves. You make the bike taller and increase ground clearance by adjusting the front fork extension and the swing arm position at the rear suspension. The job requires basic mechanical skills, metric tools and the help of an assistant.
Forks
Step 1
Elevate the bike on a motorcycle stand. If a stand is not available, elevate the bike with wood blocks under the lower frame tubes.
Step 2
Measure the vertical distance from the triple camp at the base of the steering head to the ground.
Step 3
Turn the notched adjusters at the base of the fork stems counterclockwise two turns with a shock spanner.
Step 4
Measure the distance from the axle to the triple clamp to establish the increase in fork extension. Maximum increase is 1 to 1.5 inches. If desired, repeat the procedure and turn the adjusters fully counterclockwise for maximum extension.
Swing Arms
Step 1
Measure the vertical distance from the rear axle nut to the underside of the rear fender. Note the measurement.
Step 2
Loosen the chain-adjuster lock nut with a metric wrench. Turn the adjuster bolt counterclockwise with the wrench to slacken the chain. This allows the rear swing arms to fully extend during the adjustment.
Step 3
Attach a metric wrench to the pivot-bolt at the right swing-arm hub as a backup. Loosen the nut on the opposite end of the bolt with a metric socket and ratchet.
Step 4
Ask the assistant to push down on the front of the bike as you turn the pivot arm adjuster counterclockwise with a swing-arm tool. Find the swing arms and the rear wheel lower toward the ground.
Step 5
Continue to turn the adjuster as you check the dimension from the axle nut to the underside of the rear fender. Maximum adjustment is between 1.5 and 2 inches. Tighten the swing-arm pivot nut with the socket and ratchet. Readjust the chain tension once the bike is off the stand or wood blocks.
References
Things You'll Need
- Motorcycle stand or wood blocks
- Measuring tape
- Metric wrenches
- Shock spanner
- Metric socket and ratchet
- Swing arm tool
Writer Bio
William Machin began work in construction at the age of 15, while still in high school. In 35 years, he's gained expertise in all phases of residential construction, retrofit and remodeling. His hobbies include horses, motorcycles, road racing and sport fishing. He studied architecture at Taft Junior College.
