CHOP CULT HOME
Email Password
Search
Page 1 of 2 12 Last
  1. #1
    Senior Member

    Content on this page requires a newer version of Adobe Flash Player.

    Get Adobe Flash player


    Join Date
    May 2011
    Posts
    231

    Default Shovelhead: Chage Square Swingarm to Round Swingarm. How?



    Switch Square Swingarm to Round Swingarm on late model shovel frame, what does it take?




    I have been looking for a pre 72 round swing arm shovel frame with good vin, and preferably in CA. But I run into plenty of GOOD late model frames that I pass on, due to the square swingarm.

    I have seen round swingarms on late model frames, but I was wondering how much modification, or adjustment are needed to make it happen. It's just taking way too long to find a pre72 frame with good VIN to come around.
    Attached Thumbnails Attached Thumbnails 00000.jpg  
    Last edited by a40nabowl; 09-09-2014 at 2:34 AM. Reason: typo

  2. #2
    Senior Member

    Content on this page requires a newer version of Adobe Flash Player.

    Get Adobe Flash player


    Join Date
    Sep 2011
    Posts
    1,399

    Default

    take the square swing arm off and put the round swing arm on
    not much more to it than that,
    for wheel selection you can run the oem 3/4" disc brake dual flange hub with a stock axle and some axle locaters from fab kevin

    or if you want to run a juice drum brake like whats shown in the pic than you can run a star hub with the appropriate year axle and spacers for the brake
    or a mid star hub with the appropriate axle and spacers for the brake

    and on shocks you cant really go lower than 12" shocks or it will bottom out on you constantly

    everything else is a direct bolt in

  3. #3
    Member

    Content on this page requires a newer version of Adobe Flash Player.

    Get Adobe Flash player


    Join Date
    Feb 2011
    Posts
    45

    Default

    That swap is a direct bolt on.

  4. #4
    Senior Member

    Content on this page requires a newer version of Adobe Flash Player.

    Get Adobe Flash player


    Join Date
    May 2011
    Posts
    231

    Default

    Wow! that is good news.

    I was reading all sorts of things, like chain and sprocket modifications, shock mount relocation, spacers on the new swing arm bolt and some other stuff.
    I read that the round swing arm lowers the back end by 2 inches, but I was not sure that you could not go lower than 12" on the shocks.

    All the swing arms I find, the specs state Pre 1972? That always clued me in as this would not be a straight forward job. But for sure I would go the juice drum brake rout.
    Last edited by a40nabowl; 09-09-2014 at 11:14 AM.

  5. #5

    Default

    Just picked up a dead stock 58-64 to throw on my 1980 FXE frame, very excited Click image for larger version. 

Name:	Screen Shot 2018-07-20 at 11.09.27 AM.jpg 
Views:	3 
Size:	23.5 KB 
ID:	85777

  6. #6
    Senior Member

    Content on this page requires a newer version of Adobe Flash Player.

    Get Adobe Flash player


    Join Date
    Oct 2013
    Posts
    204

    Default

    Quote Originally Posted by a40nabowl View Post
    Wow! that is good news.

    I was reading all sorts of things, like chain and sprocket modifications, shock mount relocation, spacers on the new swing arm bolt and some other stuff.
    I read that the round swing arm lowers the back end by 2 inches, but I was not sure that you could not go lower than 12" on the shocks.

    All the swing arms I find, the specs state Pre 1972? That always clued me in as this would not be a straight forward job. But for sure I would go the juice drum brake rout.
    What exact combination are you after? Rear disc, juice drum? I put a pan swing arm on one of my shovels and modified an old GMA disc brake setup to fit. It was relatively straight forward.

  7. #7

  8. #8

    Default

    Here's a question, it sounds like you can just re-use the shovelhead seals and bearings. anyone have an issue with that?

  9. #9
    Member

    Content on this page requires a newer version of Adobe Flash Player.

    Get Adobe Flash player


    Join Date
    Oct 2010
    Posts
    99

    Default

    seals no you cheapo. Bearings yes but you should change them too. My friend did this swap and had to go with the longer shocks for the round swing arm as it really drops the bike low enough that jumping curbs is not safe.Why not go with the square swingarm and cut the shock mounts off and move them back maybe 2 inches on the swingarm and reweld them, less modifications .Beware I did this and didn't notice that my chain guard damn near punched a hole in my wrap around oil tank, shortening the chain guard solved the problem. This was a pretty common thing around here in St Louis many years ago and was called dovetailing.

  10. #10

    Default

    Quote Originally Posted by BurnoutNova View Post
    What exact combination are you after? Rear disc, juice drum? I put a pan swing arm on one of my shovels and modified an old GMA disc brake setup to fit. It was relatively straight forward.
    I am trying to do this exact thing. I have a GMA disc brake setup for a 3/4 axle and later wheel that i used on a Harley rigid. I an now trying to run it on my round swing arm.

    I have a special axle from Tedds for the rigid, but it is a little too short for the swingarm.

    I see the special spacers from Fab Kevin that I figure will work, just need to figure out where to mount the anchor for the brake plate to attach to the swingarm, and which axle to use, or if I have to make my own.
    Since I don't have a lathe available to me, I would prefer to buy something ready made.

    Got any pics of the setup you used? Thanks!

  11. #11

    Default

    mocked mine up the other day. the original shocks from the shovel seem to be too wide and slightly touching the 58-64 swingarm. will these help?

    http://www.vtwinmfg.com/webapp/wcs/s...ductId=3318346

    also those seals are such a bitch to get out for some reason

  12. #12

    Default

    Quote Originally Posted by capomorra View Post
    mocked mine up the other day. the original shocks from the shovel seem to be too wide and slightly touching the 58-64 swingarm. will these help?

    http://www.vtwinmfg.com/webapp/wcs/s...ductId=3318346

    also those seals are such a bitch to get out for some reason
    here's what it's looking like now:

    Click image for larger version. 

Name:	599C11C5-D13E-45AF-B4A0-C9E60EACCBD5.jpg 
Views:	21 
Size:	84.2 KB 
ID:	86702Click image for larger version. 

Name:	A9E71D94-C47C-486C-86A8-B3C5E1F5D896.jpg 
Views:	21 
Size:	112.1 KB 
ID:	86703

  13. #13
    Senior Member

    Content on this page requires a newer version of Adobe Flash Player.

    Get Adobe Flash player


    Join Date
    Apr 2013
    Posts
    9,226

    Default

    Time for different (Grade 8) bolts (not stainless because shear load) and some stainless washers and nuts (preferably locking nuts, they are cheap enough) to place your shock bodies vertically. Solid spacers look a lot better but washers work in the meantime.

    If not sure of length you can use much longer bolts or allthread to mock up your fastener stack.
    Last edited by farmall; 08-23-2018 at 5:16 PM.

  14. #14
    Senior Member

    Content on this page requires a newer version of Adobe Flash Player.

    Get Adobe Flash player


    Join Date
    Sep 2012
    Posts
    12,149

    Default

    What's up with the bolts in the shocks???? Those should be studs not sideways bolts......

  15. #15
    Senior Member

    Content on this page requires a newer version of Adobe Flash Player.

    Get Adobe Flash player


    Join Date
    Apr 2013
    Posts
    9,226

    Default

    His swingarm came without them, see his pic above.

    Stud kit example with shock donuts.

    https://www.ebay.com/itm/Chrome-Lowe...4/263308669842
    Last edited by farmall; 08-23-2018 at 7:11 PM.

  16. #16
    Senior Member

    Content on this page requires a newer version of Adobe Flash Player.

    Get Adobe Flash player


    Join Date
    Sep 2012
    Posts
    12,149

    Default

    Got ya..... Yep that's what he needs alright...

  17. #17

    Default

    yeh, that's the way the bike came. thanks dudes

  18. #18

    Default

    Quote Originally Posted by Tattooo View Post
    Got ya..... Yep that's what he needs alright...
    finally got around to the studs today.... just a few q's.

    the stud doesn't fit all the way through the swingarm with ease... is this a stud-freeze and smash it in type project?

    also the stud diameter was too large for my stock shovelhead shocks, so i popped out the collar and the rubber... i'm assuming the shock donuts go inside of the shock and the stud goes through. that's what i've done, but i forgot about the little spacer that came in the kit. does that go inbetween these rubber donuts inside of the shock?

    i looked through my book for a diagram of this all but it's a shovel manual so, not there. thank you

  19. #19
    Senior Member

    Content on this page requires a newer version of Adobe Flash Player.

    Get Adobe Flash player


    Join Date
    Sep 2012
    Posts
    12,149

    Default

    Quote Originally Posted by capomorra View Post
    finally got around to the studs today.... just a few q's. the stud doesn't fit all the way through the swingarm with ease... is this a stud-freeze and smash it in type project?
    I would hope not.... You must have the wrong studs...

  20. #20

    Default

    Quote Originally Posted by Tattooo View Post
    I would hope not.... You must have the wrong studs...
    bummer. I got these:

    https://www.ebay.com/itm/Chrome-Lowe...4/263308669842

Share This



Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Log in

Log in