Mechanical brake drum/sprocket repair, sprocket is loose on the drum

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Re: Mechanical brake drum/sprocket repair

#16

Post by fishican » Mon Apr 29, 2013 9:03 pm

Saddlebagrail,

I followed your directions and everything went well. It sure does feel more solid this way. Thank you for sharing your ideas.

Joe


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Re: Mechanical brake drum/sprocket repair

#17

Post by saddlebagrail » Mon Apr 29, 2013 9:37 pm

Glad I could help you,Joe

Let's try it now :mrgreen:

Ray :)

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Re: Mechanical brake drum/sprocket repair

#18

Post by RUBONE » Tue Apr 30, 2013 4:06 am

What are you planning on doing with the sheared off dowel pins?

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Re: Mechanical brake drum/sprocket repair

#19

Post by fishican » Tue Apr 30, 2013 4:05 pm

Hello RUBONE,

I didn't use dowel pins, I used 3/16" roll pins per Saddlebagrails advice. I checked the drum against the brake backing plate and there is no problem with the clearance.

Joe

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Re: Mechanical brake drum/sprocket repair

#20

Post by Panacea » Tue Apr 30, 2013 4:11 pm

Fishican, just curious, do the allen screws fit snugly thru the sprocket?...Mike

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Re: Mechanical brake drum/sprocket repair

#21

Post by RUBONE » Tue Apr 30, 2013 4:36 pm

Joe,
I am not talking about the sprocket, I am asking about the dowels in the back of the drum, all five of which are sheared off...

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Re: Mechanical brake drum/sprocket repair

#22

Post by saddlebagrail » Tue Apr 30, 2013 5:53 pm

Panacea wrote:Fishican, just curious, do the allen screws fit snugly thru the sprocket?...Mike

Hi

Brand new hole in sprocket are .1875 inch(3/16 inch) and 10-24 socket head capscrews are .187 inch,at least those I have on hand ,bought from the Lawson dealer,hope this help,Ray

I did use either spiral roll pins(stronger than spring pins) or dowels pins again from Lawson product,by the way ,when you are doing a job like that better off buying quality stuff.

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Re: Mechanical brake drum/sprocket repair

#23

Post by fishican » Wed May 01, 2013 7:05 am

Holy smokes, RUBONE! I got so wrapped up in the sprocket that I didn’t even notice those broken dowels. I guess that shows just how much I know about these old machines.

I looked at the wheel and the holes in the hub look good so I milled off the welds and knocked the dowels out. I see that they have a shoulder on them and I got part #41425-37 out of the parts manual. I’ll call the store in the morning to see if that is still a good part number or do I have to get it somewhere else. I saw that they are available in the J/P Cycle catalog. When I get them, I’ll tack them on with that dirt cap just like they were.

Thank you for pointing the dowels out to me. I got a partially assembled / partial basket and I’m learning as I go.

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Re: Mechanical brake drum/sprocket repair

#24

Post by fishican » Tue May 07, 2013 3:17 pm

I was not able to get the dowels at the local fastener store so I ordered a set on e-bay for $11.00. I peened them over best I could and then set the dirt cover in place and tacked all five of them to it. Probably overkill but since I already had the drum pre-heated, I went ahead and tacked them.


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The drum's dowels slid into the wheel hub perfectly and the end of the dowels are flush with the backside of the hub.


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Thanks for pointing out the broken dowels to me, RUBONE. I really might not have caught them. I've never messed with these brakes and wheels before. I have 10 of the lug bolts, 5 are chromed and 5 are (Ithink) parkerized. Do you know if these are aftermarket or did they come this wayfrom HD? If they came this way, were the chrome ones on the rear or the front? I thought since there is a hubcap on the front, they might have tried to dress up the rear with the chrome bolts.

MIke,
The allen screws were not a snug fit but not too bad either. As Ray said, the holes are .1875" new. Mine had a faint wallow to them and the 10-24's that I used mic'd out at .185", so there was a little play. The roll pins centered the sprocket and after tightening all the screws, I found just over .005" total runout on center.

Thank you all for your help on this. I really appreciate anything you guys have to tell me and I'm sure I'll be back with more questions soon now that I'm not freezing my butt off in the barn.
Joe

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Re: Mechanical brake drum/sprocket repair

#25

Post by fishican » Tue May 07, 2013 3:17 pm

I was not able to get the dowels at the local fastener store so I ordered a set on e-bay for $11.00. I peened them over best I could and then set the dirt cover in place and tacked all five of them to it. Probably overkill but since I already had the drum pre-heated, I went ahead and tacked them.
DSCN1336.JPG
DSCN1338.JPG
The drum's dowels slid into the wheel hub perfectly and the end of the dowels are flush with the backside of the hub.
DSCN1340.JPG
DSCN1342.JPG
Thanks for pointing out the broken dowels to me, RUBONE. I really might not have caught them. I've never messed with these brakes and wheels before. I have 10 of the lug bolts, 5 are chromed and 5 are (Ithink) parkerized. Do you know if these are aftermarket or did they come this wayfrom HD? If they came this way, were the chrome ones on the rear or the front? I thought since there is a hubcap on the front, they might have tried to dress up the rear with the chrome bolts.

MIke,
The allen screws were not a snug fit but not too bad either. As Ray said, the holes are .1875" new. Mine had a faint wallow to them and the 10-24's that I used mic'd out at .185", so there was a little play. The roll pins centered the sprocket and after tightening all the screws, I found just over .005" total runout on center.

Thank you all for your help on this. I really appreciate anything you guys have to tell me and I'm sure I'll be back with more questions soon now that I'm not freezing my butt off in the barn.
Joe

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Re: Mechanical brake drum/sprocket repair

#26

Post by Panacea » Wed May 08, 2013 4:06 am

Do you think the dowels were sheared because someone ran the wheel without any lug nuts?

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Re: Mechanical brake drum/sprocket repair

#27

Post by RUBONE » Wed May 08, 2013 5:50 am

Dowels will break off if the lug bolts are not seated properly in the taper. the same forces that rip the rivets out will rip the dowels out, wheelies and burnouts being major culprits.

fishican,
All H-D lugs from the Panhead and Shovelhead era are parkerized, never chrome. Chrome fasteners tend to break under stress due to hydrogen embrittlement so are not used where safety is a risk.

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Re: Mechanical brake drum/sprocket repair

#28

Post by fishican » Wed May 08, 2013 3:53 pm

RUBONE,

Again, thank you for the information. I'll find five more parkerized lug bolts and get rid of the chrome.

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Re:

#29

Post by oklahoma » Fri Sep 11, 2015 9:41 pm

Sorry to bring up an old thread, but I am in the midst of this project as mine was loose and busted some rivots and the dust ring. If it is as simple as getting stainless screws and nylocks why other than OE looks would you do the other procedures mentioned (inserts or buy special tools to rivot)?

Are the stainless screws/nylocks strong enough or would it be problematic?



57pan wrote:Panacea,

FWIW, I gave up on the rivets. I just couldn't get the rivets to expand enough to fill the hole. Then they would very quickly work loose and bugger up the hole.

I got some stainless screws and used nylock nuts to fasten my sprocket to the rear drum.

Some guys eliminate the fasterners altogether and just put 3 or 4 welds on it.

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Re: Mechanical brake drum/sprocket repair

#30

Post by Panacea » Sat Sep 12, 2015 2:28 pm

As I recall if you read thru the thread, one guy used regular allen head screws and had a problem with them snapping off. The suggestion was to use a higher grade bolt. Mike

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