Ultra dumb question about lowering springs/ shocks

jasonscb750build

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So...

I've got an '82 CB750K. I bought the Cycle X progressive front fork springs kit. If I install the new spring/ washer/ spacer/ fork cap without cutting the top spacer down at all, am I even lowering the front at all?

I installed 13.0" eye to clevis rear shocks and I'm trying to determine if I need to chop anything off of the top fork spacers.

For some reason, I can't wrap my fucking head around how this kit lowers the front end.

Also, anyone know stock OEM rear shock length (eye to clevis)?

I feel like I keep finding mixed info that the factory rear shocks were 14.5" but don't have any certainty.

The idea of preload and everything else regarding the front fork suspension pile drives my fucking head and I feel like a complete idiot.

For reference, I used the Progressive manual for the spring replacement.
 

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Did you compare the new springs to the old ones?? Install a shorter spacer if you are trying to lower the front.

13 inch on the rear shocks is the stock height I believe.

Good rule is to lower the front and rear the same amount to keep the stock geometry.

But always a but,
Choppers with longer front forks are rideable - kinda. Ride it see how it feels.
 
I have heard you lower the front forks with longer spacers. I can't picture in my head how either works.
I've heard this too but just like you, I don't understand how it works. If you install shorter springs but compensate with a spacer that takes up the same distance you removed, how the hell is it lowering anything.
 
you can lower the front by setting fork higher in the triple clamps.

The springs control the way the suspension works.

If you want to lower the front the forks will be above the triple clamp up 1 inch maybe more.

to lower the rear you would get shorter shocks.

If I understand correctly you are new to motorcycles.

The spring affects the ride over bumps with a combination of oil and the spacer length.
 
you can lower the front by setting fork higher in the triple clamps.

The springs control the way the suspension works.

If you want to lower the front the forks will be above the triple clamp up 1 inch maybe more.

to lower the rear you would get shorter shocks.

If I understand correctly you are new to motorcycles.

The spring affects the ride over bumps with a combination of oil and the spacer length.
Thanks for the reply man.

The Cycle X progressive springs description says that they pair with the shorty shocks that they sell. Their shorty's are 11.3" which is 2" or more shorter than the factory shocks. So, to me, this implies that the springs also lower the front but I don't understand how without trimming the top spacers down at least 2".

I dropped my forks by lowering them in the triple but promptly put them back up because I was anticipating the fork spring kit to lower an additional 2" (raised them up originally 1.5" in the tree). The instructions say that you're supposed to trim the spacer until the top of it is flush with the top of the fork tube and then fine tune by trimming the spacer more to achieve your desired pre load. So, all that being said, I either trim the spacers or raise the fork tube's back up to achieve the level balance.
 
I use this method (scroll down):

http://www.lowridersbysummers.com/parts/index.htm

Of course, I purchased bushings in different lengths and spent less than $10. I like this method since stock appearance is maintained, stock springs are used, and the amount of preload is equal to the length of shim used (longer bushing=greater preload) if you decide not to cut the springs. Using the bushing under the piston limits the length of the rebound. This one has been lowered 1-1/2" to 2":

DP7.jpg
 
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