1978 KZ650 SR Rear Suspension

I am currently looking to upgrade the rear suspension of my 650SR, however I am having trouble figuring out which shock set will actually fit and provide the best bang for the buck. Currently riding on the stock 1978 suspension. I would like to avoid cheap Chinese parts if possible. Most of the old threads lead to dead links or I cannot find the shocks they were referring to on the market.

Has anybody ran these 12 3/4 inch (325mm) Eye To Eye - Monza shock absorber set from Z1?
( www.z1enterprises.com/yamaha-xs650-monza...em-4m4-22210-00.html )

Also looking at these shocks from progressive (14 series), but I have to buy the spring separate.
www.bikebandit.com/aftermarket-parts/sus...4?m=150643&rrec=true

Any advice at all is welcome! Thank you guys in advance!

I have Hagon shocks on my 1977 KZ650-C1 and they work great! I've had them for 12 years; 18,000+ miles. Here's a link to their website. Ed

www.hagonshocksusa.com/

Ed, Are you aware if there is a difference between the rear shocks on the SR (D1A) compared to the C1 or other models? They have a different part number but I am unsure if there is a difference in the eye to eye distance or the spring rate (45014-1009 SR vs 45014-117). Most of the info I can find are people changing the shocks on a non-SR model (which makes sense since there are less SRs)

Thanks for the advice, I will check out Hagon.

I suspect there is a difference. The experts at Hagon should be able to provide good advice even if you decide not to buy their shocks. Ed

Did you end up getting the monza shock absorber set? I’m looking at the same set right now. I run a 120/100-18 rear tire. Do you think it will result in tire rub? Thanks!

I've had the 13.25" Monza shocks on two mostly stock KZ650Bs and they work well for the money. Not the best, but surprisingly good for cheap shocks. A little height in the rear will make the bike turn a little quicker but not enough to make it twitchy. they dont rub the tire but IIRC there was a little interference with the 650B chain guard.

DoctoRot wrote: I've had the 13.25" Monza shocks on two mostly stock KZ650Bs and they work well for the money. Not the best, but surprisingly good for cheap shocks. A little height in the rear will make the bike turn a little quicker but not enough to make it twitchy. they don't rub the tire but IIRC there was a little interference with the 650B chain guard.

If there is interference with the chain guard do not cut or modify the stock chain guard. Many years ago I cut the chain guard on my KZ650 so it would not rub. After a while that chain guard ended up twisting around to the point where it actually went through the spokes on the rear wheel! Luckily the wheels on my bike are cast rather than wire spokes, so it caused no wheel damage. I was only going about 30mph when it happened but it sounded like the whole back of the bike was coming apart and really frightened the heck out of me. I tossed the chain guard which was seriously damaged and later replaced it with the narrower metal one shown below. Problem solved. Ed