Author Topic: A different kind of lowering block question...  (Read 2084 times)

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Offline Scott S

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A different kind of lowering block question...
« on: January 25, 2013, 12:19:16 PM »
 I have a set of Progressive shocks. They're about 14-14.25" center to center on the mounting holes. The spring rate is 105/150.


 Too long for my CB500. Then it dawned on me....somewhere in my garage are a set of lowering blocks that I picked up on one of my junkyard crawls. How would it work if I used the lowering blocks and the long shocks? What effect would that have on spring rate, if any?

 (And to complicate matters even more, I also have a longer CB650 swingarm that I could put on the bike....but one thing at a time)
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Offline ekpent

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Re: A different kind of lowering block question...
« Reply #1 on: January 25, 2013, 12:31:49 PM »
Shouldn't be to much hassle to bolt them up with your blocks and give it a go.Techy guys should have equations and formulas for you soon I'm sure.

Offline Retro Rocket

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Re: A different kind of lowering block question...
« Reply #2 on: January 25, 2013, 12:33:08 PM »
Get the correct length shocks mate, unless you want it to handle worse...
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Offline Scott S

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Re: A different kind of lowering block question...
« Reply #3 on: January 25, 2013, 12:50:04 PM »
 That was my thought....the shocks are listed in the "For Sale" section. They'd be great for a CB750.
 Then I was told that the lowering blocks would get the effective spring rate down. I already have all the parts, so..... I was curious.
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Offline 754

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Re: A different kind of lowering block question...
« Reply #4 on: January 25, 2013, 07:58:33 PM »
 I got to disagree..try them, you never know. The greater angle will make them a bit stiffer.
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Offline Retro Rocket

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Re: A different kind of lowering block question...
« Reply #5 on: January 25, 2013, 09:05:53 PM »
I got to disagree..try them, you never know. The greater angle will make them a bit stiffer.

Frank, you seen his bike mate.?  Every time i make a comment on suspension you do this, ever see a race bike with lowering blocks FFS.?,  they will make the bike handle worse than with the correct height shocks and the bike set up correctly.....  Not interested in a discussion AGAIN on this topic because nothing you can say will make me or anyone else that likes a nice handling bike {or that knows better}, convinced lower shocks and or lowering blocks are better....  They're not....  "try them, you'll never know" isn't a very good way of sorting suspension out.
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Offline 754

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Re: A different kind of lowering block question...
« Reply #6 on: January 25, 2013, 09:14:01 PM »
 I never said they would be better, and I do know guys that do run longer shocks to get more ground clearance..it has been done before..
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Lost quite a few CB 750's along the way

Offline scottly

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Re: A different kind of lowering block question...
« Reply #7 on: January 25, 2013, 09:31:26 PM »
Back in the '70s we would modify dirt bike suspensions by "laying down" the rear shocks, by either moving the top mount forward, or the bottom mount rearward. The intended result was a longer travel, more progressive rate suspension. It usually entailed stiffer springs, due to the increased initial leverage. I'd say give it a shot, since you have the shocks and blocks on hand. Just don't take on the Tail of the Dragon until you get a feel for it. ;) 
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Offline crazypj

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Re: A different kind of lowering block question...
« Reply #8 on: January 25, 2013, 09:32:09 PM »
I like 750 shocks on 550, improves ground clearance and heavier spring rate/better damping really shows up how crap stock fork springs are
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Offline bjbuchanan

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Re: A different kind of lowering block question...
« Reply #9 on: January 26, 2013, 05:27:36 PM »
the problem with the blocks is changing the angle and not compensating for it. Effective spring rate becomes important and you have to work with the geometry to figure out what it will be. It isn't rocket science but its more effort than going with whats known

Lots of race vehicles use angled spring shock combos due to packaging issues. you just have to sort it out is all
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Offline thelowmax

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Re: A different kind of lowering block question...
« Reply #10 on: January 27, 2013, 02:02:59 PM »
I find that the lowering blocks in general adds a sponginess to the whole rear end of the bike. You definitely lose some finessing ability as far as steering and handling around corners and such.
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Offline Retro Rocket

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Re: A different kind of lowering block question...
« Reply #11 on: January 27, 2013, 02:19:18 PM »
the problem with the blocks is changing the angle and not compensating for it. Effective spring rate becomes important and you have to work with the geometry to figure out what it will be. It isn't rocket science but its more effort than going with whats known

Lots of race vehicles use angled spring shock combos due to packaging issues. you just have to sort it out is all

I agree with everything you say there. I have an old article about the winning Yoshimura GS1000 superbike from the 70's, therer's a mention in it about what was involved in getting the shock angle correct, its just not as simple as laying the shock down some, it doesn't work like that at all.

I find that the lowering blocks in general adds a sponginess to the whole rear end of the bike. You definitely lose some finessing ability as far as steering and handling around corners and such.

Exactlly, you are adding anther component to the rear suspension that can add flex, thats the main reason i wouldn't do it at all...
I have bought 750/4's with lowering blocks and they were the first thing to come off and went straight in the bin, never even considered putting them on another bike... ;)
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Offline 754

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Re: A different kind of lowering block question...
« Reply #12 on: January 27, 2013, 06:20:53 PM »
 Hey are you not the same guy who looked at a billet set of trees, and said you would like to maybe run them on your Cerianis ?..  I you have Ceriani roadrace/GP forks, why would you want to lower the front..?
 Let me be clear here, not trying to slam you or your preferences.. Athough I can not understand that you cant stand to see people not doing things your way..

 A very long time ago I used to corner my bikes quite hard, but today that is not the case, I used to run Konis, andI also ran Loweringblocks, AND I ran shocks shorter than stock. Evenif he ran the. Shocks at adifferent angle, I think it wouldstill give him a feel for the brand..sorta like..I like the way they work, I will get the right length, springs, etc..
« Last Edit: January 27, 2013, 06:59:22 PM by 754 »
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It's All part of the ADVENTURE...

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Lost quite a few CB 750's along the way

Online Don R

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Re: A different kind of lowering block question...
« Reply #13 on: January 27, 2013, 11:43:10 PM »
I've seen lowering blocks that bolt down where the axle block bolts go. They appear more stable.  I cured an ill handling 750 by removing the blocks but it had other issues too. I ran them in the 70's and liked them. just my humble opinion.
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Offline Retro Rocket

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Re: A different kind of lowering block question...
« Reply #14 on: January 27, 2013, 11:57:30 PM »
Hey are you not the same guy who looked at a billet set of trees, and said you would like to maybe run them on your Cerianis ?..  I you have Ceriani roadrace/GP forks, why would you want to lower the front..?
 Let me be clear here, not trying to slam you or your preferences.. Athough I can not understand that you cant stand to see people not doing things your way..

 A very long time ago I used to corner my bikes quite hard, but today that is not the case, I used to run Konis, andI also ran Loweringblocks, AND I ran shocks shorter than stock. Evenif he ran the. Shocks at adifferent angle, I think it wouldstill give him a feel for the brand..sorta like..I like the way they work, I will get the right length, springs, etc..

Frank Terry has the Cerriani's and they will work, they didn't just come in one length either, i have found clamps with a dropped top clamp that will give me some room to move if i need it besides, the bikes not built yet. Its not just my way either , its my opinion of what works based on a lot more than just what i think. I also don't get the reference to riding hard, its more about knowing how the bike will react at any given time, in any given situation, anything I own will do that to the best of my ability, besides, you don't have to ride these bikes that hard to start finding their limitations at all. I suppose we all have different interpretations of "hard", i know plenty of guys older than me that ride a lot harder than I do and they don't consider their riding to be dangerous at all, its all about knowing the limitations of you and your bike, i just see no point in lowering those parameters. Yes, i have always been anal about suspension, being around road racing mates and seeing and learning what just small tweaks in settings can do to the way a bike reacts intrigued me and set me on a course of good handling motorcycles. Why take chances with something that can bite you on the arse as quick a you blink...  Anyway, i looked at the bike in question here and it looks like a nice little bike to ride, thats why i suggested new shocks, and yes, thats what i would do...
750 K2 1000cc
750 F1 970cc
750 Bitsa 900cc
If You can't fix it with a hammer, You've got an electrical problem.