XJ550 Maxim Gearbox problem

My friend has a gearbox problem with his 1981 XJ550 Maxim. When the engine is cold, it is easy to select gears, however once the engine warms up, it is very difficult to engage the gears. We have put a new clutch cable on the bike & adjusted it. We have had a look at the clutch plates which all look fine, and have just done an oil change. But the problem persists. Just wondered if anyone has had any similar problems. Any suggestuons as to what to try next would be very welcome. thanks

 

It's most likely a dragging clutch.

When you had the clutch apart, did you put the plain plates back with the tabs "staggered" at the same 72-degree intervals as they were?

The clutch throwout lever may not be in the correct "starting" position. With the lever pressed by hand all the way forward, it should line up with the rear of the little "box" cast onto the clutch housing, or even a tad "behind" it.

What oil did you use when you did the oil change?

 

thanks for that info. We will take clutch back off this week & double check the points in your advice. Castrol Power GPS 4t 10w/40 JASO semi-synthetic motorcycle oil was used for the oil change. Is this possibly too "modern" for the old XJ ?
Thanks Jim

 

additives have been known to make our clutches slip, it is best to just use plain ol dinosaur poop, though clutches slipping doesnt seem to be your problem, im stumped