Author Topic: Rear shocks for a big guy  (Read 1477 times)

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Offline dna_level_c7

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Rear shocks for a big guy
« on: November 05, 2010, 07:41:14 AM »
Hi everyone,

The weather here in Cleveland has been pretty chilly lately and we are expecting a little snow this weekend.  :(

So I decided to start some of the maintenance on the bike. I’m putting a couple orders together for JC Whitney and Z1 Enterprises and came across a set of rear shocks @ JC that seem to be exactly what I’m looking for.

http://www.jcwhitney.com/adjustable-shocks-and-springs-mc/p2007058.jcwx?filterid=d8782y1977j3

The customer reviews mention that these are extremely stiff and ride much better with the added weight of a passenger and add a little height to the bike. Mind you one of the guys was 175lbs…

I’m a bigger guy 6’4” 280lbs so I figure these would be perfect for me. I couldn’t find any threads that recommended any parts so I figured someone would benefit from the link. I will post an update once I get them on and test them out.
1977 CB750K Stock

Offline The_Crippler

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Re: Rear shocks for a big guy
« Reply #1 on: November 05, 2010, 07:59:01 AM »
I have almost the same shocks for my bike as well (and for the same reason.)

One question:  Are your bike's shocks eye-to-eye attachment like the ones in the picture?  Mine is eye-to-clovis, so it looked a little stranger there.  Just wanted to make sure their listing wasn't screwed up.

Offline Gordon

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Re: Rear shocks for a big guy
« Reply #2 on: November 05, 2010, 08:08:14 AM »
Maybe it's just me,  but I can't find any info on the length or spring rate of those shocks.  Kind of important information to be leaving out. 

Offline Duke McDukiedook

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Re: Rear shocks for a big guy
« Reply #3 on: November 05, 2010, 08:14:32 AM »
Odds are the spring rate on those pogos are way below your weight, usually most stock srpings are designed for a 160-180lb. rider.
Find a shock that actually gives you a spring rate and go from there like Gordon says.
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Offline swellguy

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Re: Rear shocks for a big guy
« Reply #4 on: November 05, 2010, 10:10:19 AM »
There seems to be a set of Chinese made shocks that look exactly like these that everyone sells for about $100. Some have eye to eye, some have eye to clevis measures. Mine are 14.25" eye to clevis measure. I;ve already been told they ride like hell but needed a cheap solution to raise my rear end.
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Rear shocks for a big guy
« Reply #5 on: November 05, 2010, 10:33:50 AM »
I believe Progressive offers different rate springs on their shocks.
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Offline dna_level_c7

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Re: Rear shocks for a big guy
« Reply #6 on: November 05, 2010, 01:44:56 PM »
I have almost the same shocks for my bike as well (and for the same reason.)

One question:  Are your bike's shocks eye-to-eye attachment like the ones in the picture?  Mine is eye-to-clovis, so it looked a little stranger there.  Just wanted to make sure their listing wasn't screwed up.

@ The_Crippler - how is the ride? I think my shocks have been bottoming out and my back has been killing me lately. This is my first bike so I don't know what a "good" ride feels like.

The picture is just for reference and not the actual product so I don't think it will be a problem.

Odds are the spring rate on those pogos are way below your weight, usually most stock srpings are designed for a 160-180lb. rider.
Find a shock that actually gives you a spring rate and go from there like Gordon says.


I emailed the MFG for some more information, I haven’t heard back but I hope to.

I did do some searching through other forums and found this nice chart. Not sure what it’s worth but it more than I had. He did mention these are ballpark figures.

a 100 lb rider needs 77.5#/in springs
a 150 lb rider needs 89.3#/in springs
a 200 lb rider needs 101#/in springs
a 250 lb rider needs 113#/in springs
a 300 lb rider needs 125#/in springs
a 350 lb load needs 147#/in springs (assumes that this is a 200# driver with a 150# passenger)

The Emgo springs can be adjusted from 160 to 190 lbs and people in the reviews say that they a bit longer than stock (about an inch) – I think they will be a decent upgrade considering that I most likely have 33 year old shocks on the bike currently!

So what do you all think?
« Last Edit: November 05, 2010, 01:53:22 PM by dna_level_c7 »
1977 CB750K Stock

Offline Silverback

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Re: Rear shocks for a big guy
« Reply #7 on: November 05, 2010, 02:55:30 PM »
I'm 220 and went with the heavy duty progressives. Those along with a front end rebuild made the bike handle great, relatively! Full Ohlins on my other bike have me spoiled. I did have to crank them all the way up to get the feel I was looking for, so not sure if they would work for you, or maybe I just like the ride a little more firm than most. You should also change the fork oil to suit your size (I'm using 15W) with maybe a few spacers in there to increase preload. You want the bike to compress and rise at the same rate, front and back, when you push on the center point of the bike (i.e. where you sit). Fork oil is about the only way to modulate this, unless you buy some uber expensive suspension components with dampening adjustments.
Chris
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Offline Duke McDukiedook

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Re: Rear shocks for a big guy
« Reply #8 on: November 05, 2010, 03:24:11 PM »
Oil , valving and spring rate affect compression and rebound.
"Well, Mr. Carpetbagger. We got somethin' in this territory called the Missouri boat ride."   Josey Wales

"It's Baltimore, gentlemen. The gods will not save you." Ervin Burrell

CB750 K3 crat | (2) 1986 VFR750F

Offline Silverback

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Re: Rear shocks for a big guy
« Reply #9 on: November 05, 2010, 03:48:53 PM »
I guess my point was that valving options (guess you could drill or get the simulators), or spring rates aren't readily available for the CB's basic fork and shock options. Well, at least I haven't seen any obvious suppliers that don't charge lots of $$$$.

I just bought the shocks and tried to match the front using different oils.
Chris
"It's hard to define soul. You get it in art. You get it in music, and occasionally you get it in machinery."
78 CB750F racer
78 CB750F stock
75 CB750K Baby Blue Sold (She was a great bike!)
71 CB750K (rusty rod)
77 cb550F Sold :(  Bought it Back :)
Basket case 73 CB750, 77 CB750F (Building now)
01 Aprilia Falco
76 kz400
96 BMW K1100LT