Clutch Parts for Big Twin 1990-1997

1340 Evo clutches from the nineties (1990-1997)

More friction plates, a new diaphragm spring and a completely modified tensioning mechanism, the clutch hub is an aluminum casting and a double-row ball bearing for the clutch basket, which guides even better than its predecessor. This is how you could describe the main innovations in the clutch of the big Twins from 1990 onwards. The clutch plates, the spring and parts of the release mechanism are identical parts to the Sportster models. With the 5-speed transmission of the Sportster models, the clutch production and stock-keeping of the Motor Company is also standardized and simplified.

What to consider for the clutch on Big Twins 1990-1997?

There are two different versions of the clutch basket. The basket is not a cast aluminum part as it was until 1989, but a combination of manufactured and riveted or pressed individual parts. Between two of the friction plates there is a spring washer instead of a steel washer, which makes disengaging and engaging the clutch a smooth operation. By the way: if you throw out this spring washer, you can fit two steel washers and an additional friction washer instead. The Barnett Extra Plate Kit is a proven solution for transmitting increased power.

Avoiding the "predetermined breaking point"

The weak point of the whole design is the tensioning of the diaphragm spring. The clutch pressure plate and the spring must be threaded onto eight lugs that protrude from the clutch hub. The spring is then tensioned with the spring seat, a steel ring, inside the lugs and the spring seat is secured with a retaining ring, which must sit precisely in grooves on the inside of the clutch hub lugs. When removing or inserting this retaining ring, the nervous or inexperienced mechanic regularly breaks off the aforementioned lugs and then a new clutch hub is due. Without special tools to tighten the diaphragm spring properly, nothing works here.