Author Topic: 78 Cb550 .. Stiffer Fork spring recommendations. ??  (Read 1725 times)

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Offline evopgt

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78 Cb550 .. Stiffer Fork spring recommendations. ??
« on: August 22, 2017, 06:42:04 PM »
On my bike,  78 cb550. Are there any Fork springs available out there that you guys recommend that will stiffen the forks and to minimize the travel?? I put new seals in and 15wt fork oil.  Still seems a little soft and slow to return to height after braking. Thanks guys.. I've also read of spacers between the cap and spring?? But this seems rigged to me?  Thoughts? I see some different brands of progressive springs available, are these stiffer than stock??
« Last Edit: August 22, 2017, 06:53:34 PM by evopgt »

Offline evopgt

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Re: 78 Cb550 .. Stiffer Fork spring recommendations. ??
« Reply #1 on: August 22, 2017, 07:13:19 PM »
Can you buy the spacers anywhere?? Or is this something  I should fabricate myself? I'm about 5 11. 225lbs.  I raised the forks through the triple about 1 1/2" and want to make sure travel is limited a little more to prevent bottoming out. I'm assuming stock springs are single rate?
« Last Edit: August 22, 2017, 07:21:38 PM by evopgt »

Offline przjohn

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Re: 78 Cb550 .. Stiffer Fork spring recommendations. ??
« Reply #2 on: August 22, 2017, 07:28:53 PM »
You can just use small pieces of PVC pipe for preload spacers. Get a small length at the hardware store and start out with like a 1" long piece and see how it feels.
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Offline evopgt

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Re: 78 Cb550 .. Stiffer Fork spring recommendations. ??
« Reply #3 on: August 22, 2017, 07:35:32 PM »
Thanks.. I'll try it out.    Maybe metal would be better?

Offline Scott S

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Re: 78 Cb550 .. Stiffer Fork spring recommendations. ??
« Reply #4 on: August 22, 2017, 07:39:07 PM »
 The PVC is fine. Add a washer between the spring and spacer if you want.
 I've always found Progressive springs (and shocks) to be very stiff, even when I've called them and supplied them with rider weight, bike weight, intended use, etc. That's just my personal opinion.
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Offline evopgt

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Re: 78 Cb550 .. Stiffer Fork spring recommendations. ??
« Reply #5 on: August 22, 2017, 08:52:05 PM »
Yes CalJ. That's what I'm concerned about mostly. I want the look of the lower front , but want to be safe also. I'm also going to add a front fender to keep any death wobbles from occurring. The fender should also provide a barrier between the triple and the tire should I hit a speed bump at 50. I'm gonna try a 1" spacer on each fork. , if I don't like it I'll buy new springs.   Thanks guys. Always helpful.
« Last Edit: August 22, 2017, 08:55:42 PM by evopgt »

Offline scottly

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Re: 78 Cb550 .. Stiffer Fork spring recommendations. ??
« Reply #6 on: August 22, 2017, 09:20:48 PM »
Stock 550 springs are progressively wound. 750 springs are straight-rate springs, and vary in length depending on the year; early have a shorter spring with a steel preload spacer, and late have a longer spring with no spacer.
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Offline flatlander

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Re: 78 Cb550 .. Stiffer Fork spring recommendations. ??
« Reply #7 on: August 23, 2017, 01:36:03 AM »
chances are that the 40 year old original springs are tired and mushy. replacing them is a good starting point.
progressive seems to be a favourite brand in the US. over here in europe, and maybe also available there, wilbers makes springs that are progressively wound and a bit stiffer for more sporty ridinig, and wurth are generally a bit softer for comfort.
if you buy new springs they usually come with a recommendation for oil weight and amount. amount can be measured from the top, i.e. hight of oil level in fork. make sure it's fully extended when you measure, i.e. front wheel off the ground.

you say you want to minimise travel. why? you expect lower bumps than honda anticipated? if you use spacers to fine-tune spring preload you will of course affect travel but i don't see the point of minimising travel for its own sake, unless you ride under very controlled conditions?

when buying fork oil, be aware that the weight indication on the bottle often has nothing to do with the "real" weight and varies between manufacturers. here's a good reference: http://www.peterverdone.com/wiki/images/a/a7/PVD-ISO-Viscosity-Data.gif


Offline Deltarider

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Re: 78 Cb550 .. Stiffer Fork spring recommendations. ??
« Reply #8 on: August 23, 2017, 02:21:49 AM »
What about your rear shocks? Are they functioning OK? Are they still the original 'bicycle pumps' or have they been replaced. 
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Offline evopgt

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Re: 78 Cb550 .. Stiffer Fork spring recommendations. ??
« Reply #9 on: August 23, 2017, 04:41:34 AM »
Rears are replaced

Offline evopgt

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Re: 78 Cb550 .. Stiffer Fork spring recommendations. ??
« Reply #10 on: August 23, 2017, 05:11:36 AM »
Can I buy shorter Fork tubes?? Where?

Offline evopgt

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Re: 78 Cb550 .. Stiffer Fork spring recommendations. ??
« Reply #11 on: August 23, 2017, 05:36:12 AM »
Never mind.. just read the hazards associated with that.  Sheesh