The Rebel 500 rear shocks bottom out easily – so you need to set them between 3 and 5. I have mine set on 5.
SHOCKS THAT FIT REBEL 300/500:
•Progressive shocks for Harley XG- $150. Read the Rebel 3 forum article on changing the bushings to 14mm. https://www.ebay.com/itm/204116393844?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=Z3k6_gkNSR-&sssrc=2349624&ssuid=spib5pU7T1e&var=&widget_ver=artemis&media=COPY
•Honda Rebel YSS G362 Piggyback Shocks – this owner says these shocks can be adjusted for lower height plus have a softer ride than his Diablo shocks. Webbike $702 USD plus shipping. https://youtu.be/-wjXUyuTGgA
•Ohlins shocks – check out this post in the Rebel forum: https://www.hondarebel3forum.com/threads/update-ohlins-front-and-rear-suspension-now-installed.12203/

•Rebel 300/500 shocks – The Rebel 1100 shocks fit! They are 12″ (300 mm) – same length as the 300/500 shocks. The Burly Brands Stilletos for the 1100 fit, also. They are 13″ (325 mm). If you buy the Burly Brands Stilletos, keep in mind you need to have the four collars. The Rebel shock bushings are 14mm – the Burly Brands bushings are larger – that is why you need the collars.
•Drag Specialties 12 inch Shock Absorbers Part Number XF-2-1310-1311 $169/pair shipped. I would order these, but I have nothing to show if they would be an improvement.
•Hagon shocks for the 2017-2019 Rebel … (review: “Running a set of 330MM Hagon rear shocks and working fine! They have a 18KG/100lb spring rate. The CX project weighs in at 400lbs with 3 gallons of fuel and 620lbs with rider & gear. Only ride this bike solo.”)
•I found some used 2012 Harley Davidson 54662-09 air shocks in good condition for $129 USD shipped. They are probably 12 inch. I feel confident these will help because I put these on a bike before.
•Moto Guzzi V7 shocks I believe are better than the Rebel shocks and they do not bottom out as much. They have 14mm bushings but had different lengths. Black is harder to find – many are chrome.
•Rebel shocks were improved for 2020 (stiffer spring rate). I put them on my 2017 Rebel 500. https://wp.me/PdeiSF-T8
•(not recommended) I tried some MDI YD412C shocks I have. With preload set on “1”, the response to bumps was only a little better. Next I am trying “3”. They are taller (13 1/4 inch). Weight is 3.54 lbs each. Cost about $90/pair USD. I had to order larger bushings (14mm). They are too hard, so I took them off.
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The stock rear shock center to center is 11 7/8 inches to 12 inches. Bushings are 14mm. Weight is 4 lbs
With no load, the stock shocks are about 3/16 inch longer when on “1” setting (lowest pre-load).
It’s a good idea to remove the shocks every few years and clean and grease the mounting pins. I just did it and I expect some of the squeaks/creaks that I hear to go away. My mounting pins were rusty.
It makes it easier to remove the shocks if you jack up the engine about one inch.

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If you have not actually bought a Rebel yet, consider a CB500F (31″ seat height) or CB500X (32.5″). Both have a little more comfortable ride than the Rebels.
bikes with single rear shock
CB300R ABS fairing
CB500R ABS fairing
CB300F ABS naked
CB500F ABS naked
CB500X ABS adventure
NOTE: A shock which is slightly longer than stock may alter the head angle slightly and provide somewhat quicker steering.
NOTE: A shock which is slightly shorter than stock may alter the head angle slightly and provide somewhat slower steering.
A gel pad or aftermarket seat (like Mustang) will help. I added a Mustang seat – on hard bumps it does save my back but the bike still jumps so it needs different tires and different rear shocks.
Radial tires have improved ride quality, handling, smoothness, wet weather traction, resistance to ruts/grooves/seams in the pavement, and less rolling resistance.