Rust Drops on Swingarm
Road Master
Joined: Mar 2018
Posts: 978
Likes: 423
From: UK
I found a number of similar problems on my previous fat Bob. The way I kept it under control was to apply acf 50 in the nooks and crannies every other wash and if I was planning to leave it a few weeks before riding again (late Jan to end of Feb I tend not to ride). The other 3 areas I found were under the seat where the frame joins (poor design of the end of the rear fender and gap for the softail shock results in muck gets kicked up from the back wheel if the roads are damp), side stand mounting point and both sides of the bottom of the frame cradle under the motor. Helpfully there are a couple of holes to get a nozzle inside the frame just there. On my Slim, I also noticed a rusty water trail down the front left swingarm upright. Haven't traced the source of that yet.
I reckon there's enough iron on these bikes to give plenty of years of wastage! Reasonably regular Acf50 treatment keeps it minimal. Probably WD40 would do the job, but acf has rust inhibitors in it too, it seems to convert the rust as well as a protective oily film. There other similar sprays on the market, forget the brand names.
I reckon there's enough iron on these bikes to give plenty of years of wastage! Reasonably regular Acf50 treatment keeps it minimal. Probably WD40 would do the job, but acf has rust inhibitors in it too, it seems to convert the rust as well as a protective oily film. There other similar sprays on the market, forget the brand names.
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Cruiser
Joined: Apr 2016
Posts: 161
Likes: 35
From: Buffalo, NY
I found a number of similar problems on my previous fat Bob. The way I kept it under control was to apply acf 50 in the nooks and crannies every other wash and if I was planning to leave it a few weeks before riding again (late Jan to end of Feb I tend not to ride). The other 3 areas I found were under the seat where the frame joins (poor design of the end of the rear fender and gap for the softail shock results in muck gets kicked up from the back wheel if the roads are damp), side stand mounting point and both sides of the bottom of the frame cradle under the motor. Helpfully there are a couple of holes to get a nozzle inside the frame just there. On my Slim, I also noticed a rusty water trail down the front left swingarm upright. Haven't traced the source of that yet.
I reckon there's enough iron on these bikes to give plenty of years of wastage! Reasonably regular Acf50 treatment keeps it minimal. Probably WD40 would do the job, but acf has rust inhibitors in it too, it seems to convert the rust as well as a protective oily film. There other similar sprays on the market, forget the brand names.
I reckon there's enough iron on these bikes to give plenty of years of wastage! Reasonably regular Acf50 treatment keeps it minimal. Probably WD40 would do the job, but acf has rust inhibitors in it too, it seems to convert the rust as well as a protective oily film. There other similar sprays on the market, forget the brand names.
Seasoned HDF Member
Joined: Sep 2009
Posts: 25,292
Likes: 2,427
From: Eastern NE
I wash my bike w/water maybe 2-3 times a year...otherwise it's detail spray & bug remover while I down a few post ride cold-ones. It's not a piece of art - ride & enjoy it vs. worrying about every little flaw.
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Cruiser
Joined: May 2020
Posts: 130
Likes: 59
From: MA
HD didnt treat or paint the threads under the plastic caps in the swing arm. I pulled mine for pegs and was rusted awful. Had to brush out and throw some grease on and then recap.
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Road Master
Joined: Feb 2010
Posts: 792
Likes: 258
From: N.E.Ohio
If you ride in the rain, you need to install a mud deflector under the seat and fit down under the fender. This will stop water from soaking everything under the seat. If you don't fully understand, Revelator alf on u tube has a video on it. If done correctly and fit around everything coming from the tire, it actually stays clean under the seat. 1/8 craft foam 9x11 sheets and velcro from Wally's works well.
