Is the procedure for rear sprocket change documented in the genuine manual?

[Steve Little]

Hi. Has anyone seen pictures or text of the factory method of the riveting procedure of the rear sprocket and dust cover. I looked but it might be posted under "A prick of a job"

[Chris Haynes]

A prick of a job brings up 379 threads.

[Steve Little]

��thanks Chris.
I browsed through the purple workshop manual but couldn’t see a reference to this job. Was thinking/hoping there might be a shop dope or something. I would like to try and re use the dust ring if possible so didn’t want to grind the heads off. I set it up on the mill to use a centre drill but the mushed rivet heads don’t give a true location. Hope everyone is well.
Regards Steve

[T. Cotten]

The "heads" of the rivets should be on the other side, Steve!

First I put a protective ring of sheet metal around the outside of the drum, so I could then take a 4" grinder to the heads of the rivets. It didn't matter if I scarred the old sprocket, and the dust ring could be saved after punching the rivets out on a suitable anvil (attached).

Installing the new sprocket is the hard part.

....Cotten

[Rubone]

A sharp cold chisel shears the heads right off with no grinding, punch them out and save the dust ring. The aftermarket has never supplied new rings with sprockets, but factory H-D came as a set. The factory method was to install the 4 dowel rivets first equidistant in the larger holes, then work back and forth with the remainder, like installing lug nuts on a wheel or trueing a wheel. Final setting is the last task.

[Steve Little]

Thanks for the laugh Chris. I put a laughing face emoji at the start of my comment but now it looks like two question marks?

Thanks for the instruction and tool picture Cotton. I think the pictures you have put on this forum over the years have launched a 1000 more.

Thanks Robbie. Excellent instructions and interesting bit of knowledge on factory spares. I’m guessing the self isolation isn’t hard in NM.
Hope everyone stays healthy and happy during this weird time

[Steve Little]

P4050006.jpg

First part of the job went well. Out of curiosity I tried 3 methods of removing the rivet heads.
First method was the mill.
The machine was free of jobs and still had a ¾” 4 tooth end mill in it. At 110 rpm, it cut them off with no problem but as the head came free from the body the tooth grabbed it with an unsettling chunk sound. Maybe I was running the mill too slow.

P4050008.jpg

Second method was grinding. This worked well but the sparks were heading near jobs that I didn’t want them in.
Third method was cold chisel. I started with a ¼” wide chisel but it was a bit hard to hang onto so moved to a 1” wide chisel with a 2LB hammer. Hulk smash!!
This method left the best visual for the remaining part of the rivet to hit in the hole. If I was doing a few drums in this manner I would make a fixture inside the brake area to hold it. I held it between my feet and even though that method worked well, I could see a bruised shin in the near future.

All three methods in the picture.

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I have had a new sprocket hanging up on the wall for many years. After stripping the old sprocket from the drum I got new one down and set it in place on the drum. Bugger!! It’s for the later cast drum.

P4050017.jpg

The drum and ring came up pretty nice with the wire wheel.

Thanks for the ideas

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[Steve Little]

P4050012.jpg

Wrong pic in previous post. This is all 3 methods.

[jim d]

To remove rivets I would use a round post 3/4 in. in diameter turned down to fit in a 1/2 hole in the drill press table. It should be above the table by about 1 - 1 1/2 inches. You set the under side or the rivet on the post to drill the head using a drill somewhat smaller than the diameter. Like a 5/32 drill for a 3/16 rivet shank. The reason to have it elevated above the table is so if the drill is goes off center that you can then tilt the piece that you are holding in your hand and lighten up on your drill feed pressure to guide it back to the center of the rivet head and then continue drilling. I would always drill it below the outer surface maybe 1/2 way but never the whole way. The smaller drill bit gives you a margin for error so that you don't make the hole oversize. Then support the underside over a piece of pipe or tubing held in a vise or anvil pritchel hole to remove the rivet. Always use a punch that is a little smaller than the hole that you have drilled so that when you drive it out whatever is left of the rivet head when the walls of the rivet shear that they don't tighten around the punch and jam it in the hole. Drilling the hole to a blind depth gives you something solid to drive the rivet out and shear the thin wall left. Drilling the rivet part way out will also relieve some of the internal pressure from the original riveting process. I prefer to drill the side that was peened because it was easier to remove what was left sometimes it would nearly fall out. I used to routinely remove 1/8 to 3/16 stainless steel rivets from plastic material without damage. I can't begin to tell you how many broken punches and other issues I had until I came up with a method that works. I have probably removed 10s of thousands of rivets. Maybe this will save someone some frustration and a blotched part. Riveting it together is another whole process.

[dane]

Any tips on installing?

[jim d]

On a sprocket installation I would make sure that you can fit all of the dowels and rivets into there holes at the same time. And leave a number or all of them in to hold good alignment when you start the riveting process. You may have to flip some upside down if they are loose and falling out and switch them when it is time to rivet them. I would support the factory head on the edge of a anvil face, or on a piece of 1 1/2 in. steel held vertical in a good vise with the steel stock setting on the slide and extending above the vise jaws couple of inches. You can have the support much taller for getting into a deep recess. It is important to have the head support very solid to eliminate any bounce otherwise you are always trying to hit a moving target. To maintain a nice undamaged head support it in a rivet set that fits the head and is held in the vise with support under it that is setting on the slide. On the anvil you can use a piece of copper or aluminum under the rivet to maintain the factory looking head and not have a flat spot on it. All of my ball peen hammers have polished faces so that they don't mark the rivet that I am setting. For the sprocket riveting you will need to use a punch around 1/4 - 5/16 diameter on the end with a larger diameter shank to hold on to. For any other more open unrestricted riveting I only use the ball peen hammer. Use a hammer that is appropriate for the size of rivet and type of material that you are working with. When you are ready to start riveting first slide a piece of tubing or 1/2 round stock with a hole drilled into the end bigger than the rivets over the rivet. Hit it a couple of times to draw the head down tight and pull the two pieces together. It is quite easy to forget this and start riveting without everything pulled tight. Then the rivet shank is expanded and you will need to remove it and start over. That is why you want to have all of the rivets fitting well before you start. If you have to pound them hard to get them in the hole they may not seat up tight. After you have peened the rivet with a punch or a hammer the preferred way to obtain a nice rounded finished head I use a rivet set that is the right size for the rivet and formed head. The correct size set will fit over the head and be deep enough to pull the edge of the formed head down and make the bond between the pieces tighter. I have a large amount of rivet sets and special tools that I have made for riveting but I am not sure that I can get them on here. But I could text or email them to someone if they can post them.

[doc54]

Bruce Palmer has a nice rundown on the process in his book. Back in the 70's,I had to replace the sprocket on my knuckle; I took it over to my Uncle, who was an aircraft mechanic as a hobby. He used an air rivet press to do the job. It probably doesn't look factory(I'll have to look) but it's still on there. Karl.

[pisten-bully]

Just going to supplement this helpful thread with a couple of pictures since I just got done doing this and found the information here very helpful!

The old rivet heads were flattened:
old rivets.jpg

I made up some tools to hand peen my new rivets. I have a 1" steel plate with some divets that I put in it to support the factory head. Then because the rivets are below the level of the drum and you can't peen them over with just the hammer I made up two drifts, a short one made from an old pin and a longer one made from an old head bolt, I added shallow dimples to the end of each. I added some rubber hose to the head bolt after a while to cushion my delicate hands!

tools.jpg
I was happy with the end result but not happy with how many blows I need to fully seat the rivets.... I counted one rivet taking 600+ taps with the 8oz hammer, x twelve rivets = over 7200 hammer hits! Bottom line, if I had had access to a shop with a press I would have gone there, less time and work ...plus I would have also had the original flat head style!

finsihed.jpg

[T. Cotten]

I don't like beating on things if I don't have to, Folks!

Here is my anvil where the drum is shimmed and secured so it doesn't tip when pressing the rivets.

SPKTRIVT.jpg

On the ram of the sixty-ton screw press is a motorvalve held by a fork boot. The stem of the valve was cut, and ground concave to give the proper "upset" upon the rivet, and the anvil has a similar depression to avoid flattening the head of the rivet,

....Cotten
PS: Chief drum pictured. I have an OEM H-D 45" riveting anvil if anyone is interested..

[jim d]

I normally would use a 16 oz. ball peen hammer for putting in those rivets. I have full selection of hammers and would only use a 8 oz. on much smaller rivets. As you found out it just takes too many blows because the lighter hammer just dose not have the weight and driving force needed to form the desired riveted head. Instead it is just bouncing back at you. Just think about trying to drive nails with a 8 oz. hammer versus a 16 oz. or even heavier one used for framing.