Saturday, June 7, 2014

PROJECT CX500: Progressive 412 Rear Shocks

Rear Suspension Update:
Progressive Suspension 412 Series Shocks

The CX500 build is an ever evolving platform. I ride the bike daily around the city so it's both out of necessity and desire. Considering it started as a budget build there wasn't a lot of money thrown at the systems one might want to upgrade for improved performance - like suspension and braking. I'm slowly beginning to give attention to these areas on the bike when I've got time.

First up is that rear suspension. The shocks that used to be on there were far too stiff, and just plain shitty. I think they were Emgo units but I couldn't verify because they had no markings on them. I got to talking with David Z. over at Progressive Suspension about a new set up for the rear.

On Progressive's site they list the 412-4211C shock for a CX500 which is a 13" shock with a 90/130 spring rate and a 3.89" stroke.
I was looking for a 1" drop in the rear so I ran through their catalog and picked out the 412-4049B/C models. They're a 12.00" length with a 3.01 stroke and 90/130 rate. Meaning the shocks are an inch shorter but have a .88" shorter stroke and an identical spring rate. They come in Black and Chrome I believe. I've removed the dust covers from mine. So far I love them. The ride comfort is amazing yet still sporty. They're allowing me to go for much longer rides without ass-fatigue.

I know there are a lot of other CX owners that follow the blog so just sharing the info. :)


  1. always awesome to hear about the cx.
    Speaking of upgrades, here's one that I hope will have a big bang for the buck...
    I'm upgrading my front brakes to the dual pot ones from an '82.
    Just rebuilt the caliper and will try to get it on and bleed it soon. If it is as good as I hear it is, that may be a next step you'd like to consider too.

    1. That's exactly what I'm doing next. Dual piston caliper from a CB900F. I assume it's the same one. If so you can get fully sintered pads from EBC as well, which is what I'll be running.

  2. Sweet.
    Got mine on yesterday. have the electronics off the bike as I'm about to have some welding done to the rear end for a new seat pan, but they seem to work great at stopping the bike as I roll around the parking lot.
    Good luck with yours.
    Also, you probably are already very aware of this, but just remember how messy a job it is when you detach the brake line from the existing caliper.
    My bike is no beauty in the paint department, so I wasn' t too worried about brake fluid getting on the caliper, but on the older paint, the fluid lifts it right off if it sits too long.

  3. Glad to hear a real review. I've been debating whether or not to double down and get the goods, specially since my lady needs new shocks on her CB as well... Sounds like it's worth the wait.

  4. Bike looks great, any chance you could take a pick of the whole bike to check out the stance? I'm replacing the rear shocks on my CX as well and might lower the rear. Thanks,

  5. Looks good! I like the look without the dust cover. How did you get them off?

  6. Didn't you experienced thrust problem since the shocks are shorter (236mm) than the allowed space (250mm on my bike)?

  7. Where did you get the seat? I've been looking for a good one and haven't found anything I like yet for my 81 cx500 cafe project. Thank!
    - Spencer

    1. Spencer,

      The seat was custom made for the bike. Check this out:

    2. Thanks David!