How to Change a KTM 65 SX Clutch | Back End | Features | Tricks of the Trade
The KTM 65 SX and Husky TC 65 clutch is a little different compared to most others.
Being that the KTM 65 SX can have hard-charging groms on their backs who are tough on clutches and cause them to wear out much more frequently than they do on full-size bikes. For this reason I have decided to give you guys [parents, of course] the run down
on how to change a clutch on one of these little weapons.
3 OUT SLAVE
Once you have drained the oil, remove the brake pedal and clutch slave cylinder from the clutch cover by removing the three Allen-head bolts holding it in place. You do not need to remove the hydraulic line; leave it connected and just hang the slave cylinder to one side.
9 HAVE A SOAK
Soak the new clutch plates in oil for at least 15 minutes before installing and then reassemble the centre clutch assembly with the new plates and springs by alternating between fibre plates and steel ones, starting and finishing with a fibre plate. Make sure to leave the pressure plate bolts finger tight until installed.
10 INSTALL THE PACK
Re-install the centre clutch assembly. You will need to rotate each plate so they interlock with the outer clutch basket while you line up the spline on the inside of the clutch hub. Be patient, this will be fiddly and may take a moment or two.
11 TIGHTEN NUT
Now tighten the inner clutch nut, but be sure to put Loctite on the thread before installing. Then, once again, hold the inner clutch nut with a socket while you tighten the pressure plate bolts.
13 FRESH OIL
Refit the sump plug and fill the gearbox with fresh oil. Make sure to use the 8mm oil-level check bolt on the left-hand side of the engine to get the level correct. Clean up any excess oil and then give the new clutch a work out. Technical Editor Mat Boyd
WHAT’S SO DIFFERENT?
The KTM 65 SX and TC65 clutch is unique because it works in reverse to a conventional multiplate design. The KTM 65 outer clutch hub is fixed to the gearbox input shaft and the pressure plate is on the inside, between the inner hub and the clutch basket. When the clutch is activated, the outer hub stays still but the pressure plate moves to release the force on the clutch stack so the plates can slip.
In a conventional design, the clutch hub is also fixed directly to the gearbox input shaft but the pressure plate is located on the outside, closest to the clutch cover, instead of in the centre of the clutch assembly as on the KTM 65 SX. When the clutch is actuated on a conventional clutch, the pressure plate is either pushed or pulled outwards towards the cover, not pushed inwards like the 65cc Austrian’s system.
This all means that to replace the clutch plates and springs on the KTM 65 clutch the centre hub needs to be removed while on a conventional clutch you only need to remove the pressure plate on the outside of the clutch pack, making it a much quicker and easier job.
1 Use a new gasket on the clutch cover.
2 Use a new gasket on the
clutch slave cylinder.
3 Use Loctite on the centre clutch bolt.
1 Over-tighten the clutch bolts.
2 Reuse any worn or damaged parts.
3 Force any parts into place, everything should slip together easily.
Make sure you test the clutch yourself for correct operation before you put your kid on the bike and send them straight out onto the track.