Yamaha YZ250 2021 User Manual

TROUBLESHOOTING
7-9
EAM30513
TROUBLESHOOTING OF BRAKE
EAM30514
TROUBLESHOOTING OF SUSPENSION
Symptom Possible cause Actions
Poor performance of disc brake
Worn brake pad Replace the brake pads as a set.
Worn or deflected brake disc Replace the brake disc.
Air in hydraulic brake system Bleed the hydraulic brake system.
Brake fluid leakage
Check the hydraulic brake system
and repair or replace faulty parts
as necessary.
Incorrect brake fluid level (low)
Add brake fluid to the specified
level.
Stuck brake caliper piston Replace the caliper piston seal.
Stuck brake caliper and slide pin Lubricate the caliper slide pin.
Loose union bolt
Tighten the union bolt to the speci-
fied torque.
Damaged brake hose and brake
pipe
Replace the brake hose and brake
pipe.
Oil or grease on the brake disc or
brake pad
Clean the brake disc or brake pad.
Insufficient lubrication of brake
lever or brake pedal pivot
Lubricate the brake lever or brake
pedal pivot.
Symptom Possible cause Actions
Front fork is hard
Bent or damaged inner tube Replace the inner tube.
Bent or damaged outer tube Replace the outer tube.
Damaged or worn slide metal Replace the slide metal.
Bent or damaged damper rod Replace the damper rod.
Bent wheel axle Replace the wheel axle.
Incorrect oil viscosity (high) Change to recommended fork oil.
Incorrect oil level (high) Adjust to the specified oil level.
Improperly adjusted spring pre-
load (hard)
Adjust the spring preload.
Improperly adjusted rebound
damping (hard)
Adjust the rebound damping.
Improperly adjusted compression
damping (hard)
Adjust the compression damping.

Yamaha YZ250 2021 Specifications

General

Engine Type	249cc liquid-cooled 2-stroke; reed-valve inducted
Bore x Stroke	66.4mm x 72.0mm
Compression Ratio	8.9~10.6:1
Ignition	CDI
Transmission	5-speed; multiplate wet clutch
Final Drive	Chain
Suspension Rear	KYB® single shock; fully adjustable, 12.4-in travel
Brakes Front	Hydraulic disc, 270mm
Tires Front	80/100-21
Tires Rear	110/90-19
Width	32.5 in
Height	50.8 in
Wheelbase	58.5 in
Ground Clearance	14.2 in
Fuel Capacity	2.1 gal
Wet Weight	227 lb
Fuel Delivery	Keihin PWK38S carburetor
Suspension Front	KYB® Speed-Sensitive System inverted fork; fully adjustable, 11.8-in travel
Brakes Rear	Hydraulic disc, 245mm