How To Install a Clutch Kit on a 1979 Yamaha IT250

Shop parts for a 1979 Yamaha IT250 Dirt Bike.

Why replace the clutch on a 1979 Yamaha IT250

The 1979 Yamaha IT250 is a twostroke trail/enduro machine with a wet, multiplate, cableoperated clutch. Over time the clutch can slip, drag, engage inconsistently, or feel hard to pull. Symptoms include slipping on big launches or in sand, a grabbing or chattery engagement, poor throttle response, and harder-than-normal shifting. Replacing worn friction plates, steel plates and springs restores power transfer, smooth engagement and crisp shifting essential for trail and tight-woods riding where clutch control matters.

Overview of clutch parts and what to inspect

  • Clutch cover access point; check gasket and cover threads or chips.
  • Pressure plate holds plates together; inspect for heat bluing or scoring.
  • Clutch springs provide clamping force; look for collapse or uneven length.
  • Friction plates check for glazing, thinning or burnt odor.
  • Steel drive plates watch for discoloration/warping and rough edges.
  • Clutch hub & basket inspect hub splines and basket fingers for notching.
  • Inner hub splines ensure they are clean & not excessively worn.
  • Thrust washer & pushrod confirm smooth movement and no burrs.

Preparation

Park the 1979 Yamaha IT250 on a flat surface and support it upright with a stand. Clean around the clutch cover to keep grit out. Because this is a wet clutch, you may not need a full oil drain first but if the procedure calls for removing the primary drive or you prefer a cleaner job, drain the engine oil into a pan. Have fresh oil ready if you drain. Gather a clutch kit sized for the 1979 IT250, basic hand tools, a strap wrench or soft mallet, a clean tray, and a container of compatible engine oil for plate soaking.

Removing the clutch cover & accessing the pack

  • Loosen the clutch cable at the lever and free the clutch to remove tension.
  • Remove cover bolts in a crisscross pattern to prevent warping; lift the cover free. Note gasket condition and clean mating surfaces.
  • With the cover off you'll see the pressure plate and spring arrangement. Keep parts in order as you remove them.

Removing springs, pressure plate & old plates

  • Loosen and remove the clutch spring bolts evenly to avoid tilting the pressure plate. Remove springs and lift off the pressure plate.
  • Slide out the clutch pack friction and steel plates alternately. Count the plates and note their orientation as you remove them.
  • Remove the inner hub and inspect the thrust washer and pushrod action for smooth travel.

Detailed inspection what to look for

Lay parts on a clean surface. Hold friction plates up to light to check for thinning or uneven wear; glazed plates will be shiny and may have a glazed odor. Place steel plates on a flat surface and rock them to detect warping; discoloration or blueing indicates overheating. Rotate the clutch basket and inspect each finger for notching where plates catch notched fingers cause drag or chatter. Check hub splines for rounded teeth and the inner hub bore for scoring. Measure spring free length by eye a noticeably shorter spring set means reduced clamp force and should be replaced.

Preparing new plates

Because the 1979 Yamaha IT250 uses a wet clutch, soak new friction plates in clean engine oil for at least 15-30 minutes so they absorb oil and seat correctly. Keep steel plates clean and free of debris. Arrange plates in the original alternation friction, steel, friction finishing with the correct plate type that the original pack used.

Reassembly installing the new clutch kit

  • Install the clutch hub and any required thrust washer or pushrod components. Ensure the pushrod is straight and slides freely.
  • Fit plates into the basket in the correct order and orientation. Confirm each plate fully seats into the splines and basket fingers.
  • Install the pressure plate carefully so it sits flat against the top plate.
  • Insert clutch springs and tighten spring bolts progressively and evenly until snug. Do not rely on feel for exact torque values tighten until the springs compress evenly and are secure.
  • Reconnect the clutch cable to a loose lever setting for final adjustment later.

Final assembly, oil & cable adjustment

Reinstall the clutch cover with a good gasket or properly sealed surface. If you drained oil, refill with the correct grade and amount for the IT250 twostroke engine confirm oil level per your preference for running. With the engine off, pull the clutch lever in and rotate the rear wheel by hand to ensure the clutch disengages cleanly and plates spin freely when released.

Adjust cable free play at the lever so there is a small amount of slack before the clutch begins to pull in. For a cable clutch on the 1979 IT250, check for smooth return and no binding along the cable routing. Too much free play mimics clutch wear; too little can make shifting difficult or drag the clutch.

Breakin and riding notes

After installation, ride gently for the first few miles avoid fullthrottle launches and long clutch slipping. The new friction material bedin quickly on a wet clutch, restoring crisp throttle response and better power transfer. If engagement feels spongy or inconsistent, recheck cable routing, free play, and look for oil contamination on the friction plates from previous failures.

Common clutch wear causes for the IT250

  • Aggressive starts, sand or heavy trail work accelerate plate wear.
  • Highheat riding or prolonged slipping causes blueing and warped steels.
  • Old or wrong oil can accelerate glazing and reduce clutch life.

Quick troubleshooting reminders

  • Slipping that persists after new plates often points to weak springs or not seating the plates fully.
  • Dragging after reassembly usually traces to improper cable free play or a stuck pushrod.
  • Chatter can come from notched basket fingers or uneven plate thickness.

Related Shopping Categories

Shop Clutch Kits for a 1979 Yamaha IT250 Dirt Bike.

Shop Clutch Baskets for a 1979 Yamaha IT250 Dirt Bike.

Shop Clutch Springs for a 1979 Yamaha IT250 Dirt Bike.

Shop Inner Hubs and Pressure Plates for a 1979 Yamaha IT250 Dirt Bike.

Shop Clutch Covers for a 1979 Yamaha IT250 Dirt Bike.

Disclaimer: This guide is provided for general informational purposes only and is not intended to replace your motorcycle's official owner's manual. Always refer to your manufacturer's documentation for model-specific instructions, torque specifications, safety procedures, and maintenance requirements. If you are unsure or inexperienced, consider seeking assistance from a qualified mechanic or technician.