Rear shock How to measure?

[FastCletus]

I have $200 to spend on some rear shocks.  I want a set that is good for solo riding but also with a passenger.  I under stand the term in measuring the eye to eye part. But I dont get what a clevis is.  All the listing say the shocks are supposed to 13 inches on a CB 750F 1980, but when I measure I think mine are bigger.  Can that be?

[shultz_1978]

On the 78 and older the bottom of the shock used a clevis bolt set up. Basic u-shape with threads on one side. The bolt went through one side of the clevis no threads through the swing arm bracket into the other side of the clevis that had threads to tighten the bolt into and hold the bottom of the shock to the swing arm

78 and older clevis on the bottom of the shock eye to clevis. 79 and newer eye to eye

[FastCletus]

here is what I have


Any brands anyone like in particular?  NEver bought shocks before.  Yes Ohlins would be nice, but I only have $200

[shinyribs]

Cletus,what you have is an eyelet up top,and a clevis on the bottom.

[FastCletus]

OK, but when measuring to see which shock fits do you measure from eye to top of clevis or bottom of clevis, or center of clevis

[sgtslag]

The best shocks, near that price range, are Progressive 12 Series:  Standard Duty, and Heavy Duty Springs are available.  DO NOT purchase the Heavy Duty Springs:  I did, and on their lowest setting, they are still too stiff, riding two-up, with full saddlebags, and a full trunk!  The Standard Duty will suffice, single, or double, with full luggage...  They have five pre-load settings, like the OEM shocks, and we ran our '79 K on the lowest setting with the HD Springs, bike fully loaded; on our 800# Voyager, with Standard Duty Springs, we run it at setting #2 (#1 being the softest), riding two-up, full saddlebags, and a full trunk!

The Progressives have a "progressively wound spring", which means, dual-rate springs (acts like both a heavy duty spring, for deep holes, as well as a gentler spring, for smooth roadways -- all from one spring). They are not as good as Ohlins, but they are damn nice.  I put the same model on my Voyager 1200 touring machine (OEM were air-assisted, oil filled, PITA's...).

A word of warning:  if you get the 12 Series on the rear, you will find the front Fork Springs woefully lacking -- they have those, too, progressively wound.  The full combination will transform both the ride, and the handling:  it will ride, and handle, like a modern bike -- amazing difference on my '79 K model, couldn't believe the difference, and the comfort!

Here is the price breakdown from their online catalog ("What fits my ride?") (other online sources sell them for less...  shop around -- it pays!):

12 Series Shocks (pair) for 1980 CB750F:                   $203.52
Black Springs, Standard Duty (Chrome are $16 more):   $76.95
Fork Springs (pair):                                                      $92.95
--------------------------------------------------------------------------------------------
                                                                     Total = $373.42

                              Without the Fork Springs:  Total = $280.47


With regards to measurements, contact Progressive's tech support via their web page 'contact us':  link.

[Johnnylevi]

You need 14.25" eye to clevis

[shultz_1978]

Sorry don't know what I was thinking I think Most all of the cb750 Are I to clevis Like yours

OOPPs

[shinyribs]

Johnnylevi wrote

You need 14.25" eye to clevis

Right^ Center of the top bolt hole to center of the bottom bolt hole. Regardless of shock end style,it's always center to center of the fasteners.

[FastCletus]

eye eye team.  I am going to order front springs this week and rear shocks next

[FastCletus]

Ok got front springs on order. Now rear shocks. Why can't I find any 14.25 shocks but tons of 340 mm?  All the ads say the 340mm fit 750. I assume the 340mm will fit my bike

[sgtslag]

Visit this link:  Progressive 14" Rear Shocks for 1980 CB750F.  These (P/N:  12-1205B, 14" Rear Shocks) should work, but you can contact Progressive, directly (Contact Link), to verify if you want.  Cheers!

[FastCletus]

I know about those ones, but it seems like thats my only choice. How can that be?

[sgtslag]

Your only choice?  Not sure what you mean.  Progressive manufactures products for many bikes, of many years and models.  They can't produce six different shocks for one model of bike, from 30 years ago -- there isn't enough profit in it, or they would.

If you mean, why are there not other choices, from other manufacturers?  Well, there probably are, but we're talking about a bike more than 30 years old...  Same old profit issue.

Like I said, I put the Progressive brand on my '79 CB750K, and I loved them so much, I put their products on my '93 Voyager touring bike -- researched them, found they are highly regarded by Voyager owners across the USA, so that helped my decision, of course, even more.

If I have misinterpreted your question, let me know.  You may need to spell it out/explain it like I am in Kindergarten, though, so I can understand it -- I can be a little thick in the head, at times.    Cheers!

[FastCletus]

I guess I just mean more manufacturers. I look on ebay and there are a ton that are 13.25 inches or 340mm. But only one choice for 14.25 inch?  The 13's are under 100 but  the 14's are all over 200. No huge deal I guess I just wanted someone to say "oh yeah, the 340mm, they are fine for your bike"

[icerigger]

Check out Vintage750. They've got some that are a little more economical.

[Lucky 1]

340mm=13.385 inches