I was thinkin a while back that if I put stiffer oil in the front diff, it would make the visco lock stiffer. So, I put 20w50 in it. It worked, but the steering was hard - even stinking hard in the cold. I think even I posted complaints about it.

But, I changed the front diff oil again due to the brass looking flecks that were in the oil the first time, but this time I put Mobil 20w50 V-twin in it (the front diff takes the same stuff as the motor). Wow, did it make a difference, the steering is easy. I feel that it is easier than when it was new. I am sure the visco lock is not as effective, but grabbing that little yellow lever above the left handle grip fixes that.

Anyone wondering why the steering is so much easier with synthetic in the diff needs to realize that synthetic is much less viscous than dino oil when cold, and not as thin when hot. The limited slip clutches in the front diff resist the front wheels turning independently, therefore they try to make your handlebars straighten (try locking the diff when turning, you will really feel it, :-) but be careful)

Just thought someone here might like to know what different oil in the front diff does to the steering. I am not sure if that was the right thing to put in, since the diff and engine run at different temperatures, mobil v-twin is right for the engine, but may not be right for the front diff. I dunno.

 

Mine also had the flakes in the front diff. oil. Does anyone know what material the clutch pack disks in the front differential are made of and if some wearing is normal for the limited slip type diff., or is this a real problem? -I found them in the service manual, copper and steel........