How To Install a Clutch Kit on a 1980 Yamaha IT250 Dirt Bike

How To Install a Clutch Kit on a 1980 Yamaha IT250

Why replace the clutch on a 1980 Yamaha IT250?

The 1980 Yamaha IT250 is a two-stroke enduro bike built for trail and light offroad competition. It uses a cableoperated, wet multiplate clutch, so wear shows up as slipping under power, dragging or delayed engagement, inconsistent lever feel, or hard shifting. Aggressive starts, heavy trail work in mud or sand, and high heat accelerate clutch wear. Replacing the clutch restores direct power transfer, crisper throttle response and predictable shifts.

Tools & prep

• Basic hand tools: socket set, metric wrenches, screwdriver set, clutch holding tool or improvised holder.
• Needlenose pliers, a drain pan, clean rags, and fresh engine oil suited for twostroke wet clutches.
• New clutch kit (friction plates, steels, springs, and any supplied washers), possibly a new clutch cable if stretched.
• Shop the bike on a level surface, use a stand to keep the rear wheel off the ground, and let the engine cool.

Initial checks and preparation

Before opening the clutch, check cable free play and lever feel. On the 1980 IT250 the cable acts on a cable arm excessive free play or binding can mimic worn plates. If the cable is tight but the clutch slips, proceed to inspect internally. For a wet multiplate clutch plan to drain the crankcase oil unless you prefer to catch and reuse it with a filter change. Clean the exterior of the clutch cover and surrounding area to prevent contamination.

Removing the clutch cover

• Drain oil into a pan if you want to replace or check oil condition. Remove plug and allow most oil to drain.
• Loosen and remove clutch cover bolts, keeping track of bolt lengths and any shims or dowels.
• Gently pry the cover away, watching for gasket material or Orings. Drain any residual oil into the pan.

Clutch disassembly

• Loosen the clutch spring bolts evenly in a crisscross pattern to prevent misalignment. Remove pressure plate and springs.
• Remove the pressure plate and the stack of friction and steel plates. Note the order and orientation of plates many IT250 kits start and end with a friction plate but confirm by observing the stack.
• Inspect thrust washers and pushrod (where present) for flatness and wear. Remove the inner hub nut if needed to access the hub and basket, using a clutch holding tool to prevent rotation.

Inspection what to look for

• Friction plates – look for glazing, excessive wear, or thinning. Slight burn discoloration is common; deep glazing or missing friction material means replacement.
• Steel drive plates – check for blueing, heat spots, or warpage. Warped steels will cause chatter and poor engagement.
• Clutch basket – inspect basket fingers for notching where plates engage. Notches cause the plates to hang up and mimic slipping.
• Inner hub splines – check for rounding or heavy wear. If splines are damaged, the hub may need replacement rather than only plates.
• Springs – confirm free length and that springs are not collapsed or uneven. Replace springs included in the kit if they show signs of fatigue.
• Thrust washer & pushrod – ensure the thrust surface is smooth and the pushrod moves freely; any burrs or deformation reduce engagement quality.
• Oil condition – thick, dark or contaminated oil accelerates clutch wear. Plan to refill with correct twostroke oil or premix requirements for this model.

Preparing new plates

Soak new friction plates in engine oil for at least 20-30 minutes so they fully absorb oil. This minimizes initial slippage and accelerates proper breakin. Have the new steels at hand and check they are flat and free of burrs.

Reassembly building the clutch pack

• Arrange plates in the proper order as removed. For the IT250 this typically alternates friction then steel, finishing with a friction plate; mirror the original stack orientation you removed.
• Slide plates onto the hub ensuring they seat correctly in the basket fingers and hub splines. If a plate binds, rotate and re-seat rather than force it.
• Install the pressure plate and evenly tighten the clutch spring bolts in a crisscross sequence to compress the springs uniformly. Tighten to snug without overpreloading the springs; avoid using impact tools.
• Reinstall any thrust washer and pushrod components, confirming free movement and correct seating.

Final assembly and adjustments

• Carefully refit the clutch cover with a clean gasket or fresh sealant surfaces. Reinstall bolts in their original positions.
• Refill the crankcase with fresh, correct oil for a twostroke wet clutch setup or follow the bike's fueling/oiling practice if premix is used.
• Adjust clutch cable free play at the lever and at the actuator arm. On the cableoperated IT250 you want light free play so the clutch fully engages at rest but isn't dragging.
• If you replaced the cable, route and lubricate it to reduce binding and ensure smooth travel.

Breakin and testing

Start the engine and check for unusual noises or leaking at the cover. With the bike on a stand, test clutch engagement through the gears; listen for chatter and confirm smooth release. On the trail, ride gently for the first few miles to allow plates to bed in, then recheck cable free play and inspect for oil leaks.

Practical riding context for the IT250

The 249cc twostroke IT250 is forgiving but builds clutch heat quickly during tight technical riding or frequent launches. If you ride woods, sand or aggressive hill climbs, expect increased clutch wear and prioritize spring replacement and fresh oil. Proper installation eliminates throttle lag, reduces clutch slip on hard acceleration, and restores crisp shifts in trail and enduro conditions.

Final tips

• Keep parts clean and organized during disassembly so the reassembly order is clear.
• Replace clutch springs with the new set from the kit if they show any sign of fatigue.
• Address any basket or hub damageplates alone won't cure notched baskets or rounded splines.
• After a few rides, recheck cable free play and cover bolts for proper seating.

Related Shopping Categories

Shop Clutch Kits for a 1980 YAMAHA IT250 Dirt Bike.

Shop Clutch Baskets for a 1980 YAMAHA IT250 Dirt Bike.

Shop Clutch Springs for a 1980 YAMAHA IT250 Dirt Bike.

Shop Inner Hubs and Pressure Plates for a 1980 YAMAHA IT250 Dirt Bike.

Shop Clutch Covers for a 1980 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.