Post by richard on Sept 27, 2010 18:59:11 GMT -5
After rebuilding the top end of my 71 XS650, I started riding it around. Everything was working well for the most part, but there was a small intermittent noise in the engine that caught my attention, and the clutch seemed to slip a little in the hills, so it would get hot and kind of grab making shifting sticky. It wasn’t all that bad for the first ten or fifteen miles, so I thought I would put some miles on it and do a clutch inspection again on the next oil change. In the mean time, I bought a spare clutch for parts, a new thrust bearing, new springs and new screws and bushing for the clutch boss. Well, at 140 miles I had enough of the clutch and decided to take it apart to see what’s going on. Here is what I found.
Here is the right Cover Taken off
This is the stock clutch basket with my felt pen marking on the screws from when I looked at it before the rebuild. I marked the scews so that I could see how much they turned when I hit them with the impact driver. I didn't want to strip them so I made them tight plus about a 1/8 of a turn.
Next I cleaned and marked everything so that it would go back together the way it came apart. It helps to keep things balanced since this clutch has no indexing marks.
This is typical grooving on the basket and boss. I have seen a lot worse so I just filed the fingers the first time I looked at it and called it good. This time I was going to be more particular since I was still having problems.
Here are some of the disks removed. You can see the grooving that needs to be smoothed out with a file.
This is the push rod end that releases the clutch
It slides out and there is a ball bearing behind it.
This is the ball with oil holding it in place
I used a magnet to take it out
Here it is with the nut removed
and here is the engine case with the clutch removed.
At this point, I wanted to look at the shift linkage for signs of wear, but it looked ok so I didn't change anything.
This is the thrust bearing and washer as it came off.
This is the bearing and washers. I noticed the washer wasn't bad, but it did have a little wear so I replaced them all.
I thought this was interesting. I never had this part of the clutch off, but the first thing I noticed was the dampener springs looked different. Three of one kind and three of a smaller size that just didn’t seem right to me, and after looking at it I figured out the small springs were pushing out and making contact with the engine case. These springs are known to break, but they are a pain to change because you have to remove and re-rivet the gear onto the basket once the springs have been replaced. I hate to mix and match, but the spare clutch basket I bought had the correct springs and appeared to be in better shape the my original basket so at this point I decided to use it.
Here is what the lose springs did to the case and I picked up the shavings in my oil filter.
This is a closer view.
Once I filed all the basket fingers and smoothed the splines in the boss, I used fine emery cloth to knock down the burs so everything would move freely.
This is the Basket cleaned up and back on the bike. I remarked it using the casting numbers as a reference.
I soaked all the disks in the oil to make sure they would not be dry at first use.
When I inspected the friction disks, I found one broken so I replaced it with one of my spares. The disk was complete except for this crack. I put a towel in the crack otherwise you couldn't see it with the camera. I must have missed this last time I had it apart which could account for some of the drag on the clutch.
Then I installed new Vesrah springs that are plus 14% over stock. I used new bushing type scews from Mike's. The new springs were a half inch longer than the stock springs I took off, but the clutch lever pull seemed fine once they were on. I hate stiff clutches.
This is the clutch back on, new parts and all. I had one spring left to put on. The reference mark is off because I was moving it around to check the spring tension before I put the last spring on.
The rest is basic assembly and to be honest I forgot to takes pictures on some of it. I used one of Mike's improved thrust bearings, but I didn't put it directly on the boss because after 30 years of working on machines, I just couldn’t bring myself to mate a bearing to a surface with two dissimilar metals no matter how smooth the appeared. The thick washer seemed like the most logical surface to roll a bearing on so I thought putting it between two washers would get the best results. I guess time will tell. The test ride went well, but longer rides will be a better indication of any improvements.
Here is the right Cover Taken off
This is the stock clutch basket with my felt pen marking on the screws from when I looked at it before the rebuild. I marked the scews so that I could see how much they turned when I hit them with the impact driver. I didn't want to strip them so I made them tight plus about a 1/8 of a turn.
Next I cleaned and marked everything so that it would go back together the way it came apart. It helps to keep things balanced since this clutch has no indexing marks.
This is typical grooving on the basket and boss. I have seen a lot worse so I just filed the fingers the first time I looked at it and called it good. This time I was going to be more particular since I was still having problems.
Here are some of the disks removed. You can see the grooving that needs to be smoothed out with a file.
This is the push rod end that releases the clutch
It slides out and there is a ball bearing behind it.
This is the ball with oil holding it in place
I used a magnet to take it out
Here it is with the nut removed
and here is the engine case with the clutch removed.
At this point, I wanted to look at the shift linkage for signs of wear, but it looked ok so I didn't change anything.
This is the thrust bearing and washer as it came off.
This is the bearing and washers. I noticed the washer wasn't bad, but it did have a little wear so I replaced them all.
I thought this was interesting. I never had this part of the clutch off, but the first thing I noticed was the dampener springs looked different. Three of one kind and three of a smaller size that just didn’t seem right to me, and after looking at it I figured out the small springs were pushing out and making contact with the engine case. These springs are known to break, but they are a pain to change because you have to remove and re-rivet the gear onto the basket once the springs have been replaced. I hate to mix and match, but the spare clutch basket I bought had the correct springs and appeared to be in better shape the my original basket so at this point I decided to use it.
Here is what the lose springs did to the case and I picked up the shavings in my oil filter.
This is a closer view.
Once I filed all the basket fingers and smoothed the splines in the boss, I used fine emery cloth to knock down the burs so everything would move freely.
This is the Basket cleaned up and back on the bike. I remarked it using the casting numbers as a reference.
I soaked all the disks in the oil to make sure they would not be dry at first use.
When I inspected the friction disks, I found one broken so I replaced it with one of my spares. The disk was complete except for this crack. I put a towel in the crack otherwise you couldn't see it with the camera. I must have missed this last time I had it apart which could account for some of the drag on the clutch.
Then I installed new Vesrah springs that are plus 14% over stock. I used new bushing type scews from Mike's. The new springs were a half inch longer than the stock springs I took off, but the clutch lever pull seemed fine once they were on. I hate stiff clutches.
This is the clutch back on, new parts and all. I had one spring left to put on. The reference mark is off because I was moving it around to check the spring tension before I put the last spring on.
The rest is basic assembly and to be honest I forgot to takes pictures on some of it. I used one of Mike's improved thrust bearings, but I didn't put it directly on the boss because after 30 years of working on machines, I just couldn’t bring myself to mate a bearing to a surface with two dissimilar metals no matter how smooth the appeared. The thick washer seemed like the most logical surface to roll a bearing on so I thought putting it between two washers would get the best results. I guess time will tell. The test ride went well, but longer rides will be a better indication of any improvements.