Older Hagon Shocks Too Firm

I have an older set of Hagon Gas shocks with few miles on them. The problem is they give a really hard ride. I removed the spring planning on using a shorter spring. However the Hagon spring is the same length and similar diameter as a stock Norton Girling shock. So why is the ride so hard?? Because the lower spring stop, in the most relaxed position, is about an inch higher than a stock Norton Girling shock. In other words, there is a ton of preload.

Anybody else run into this problem? Any simple solutions? I have a gunnysack of old Girling shocks but it looks like they are all the same length. Anybody had any success shortening a spring using heat or by chopping it? There is a shroud on the shock so the mod would be hidden.

Stephen Hill

Same number of coils? How much does the rider weigh?

ahh - because hagons suck?

The oplde N.O.C. story was 110lb springs for solo .

My Gas Girlings came with 110 Lb springs . :mrgreen:
Still stiff for 10 stone rider - good for scratching , but
compliant two up - so the 145 Lb are Touring Springs .

The only adjustment n old Girlings is Pre Load - Thus ride hight . Naff All but backed off solo , wound up two up .
If your seats are higher , the open position might be a start . But if your not 15 stone , lighter springs perhaps .

Matt Spencer said:

The oplde N.O.C. story was 110lb springs for solo .

My Gas Girlings came with 110 Lb springs . :mrgreen:
Still stiff for 10 stone rider - good for scratching , but
compliant two up - so the 145 Lb are Touring Springs .

The only adjustment n old Girlings is Pre Load - Thus ride hight . Naff All but backed off solo , wound up two up .
If your seats are higher , the open position might be a start . But if your not 15 stone , lighter springs perhaps .

Click to expand...

+1

Maybe a previous owner changed the poundage of the springs sometime, or you have them ajusted on max setting, you will need a "C" spanner.
On the Hagon and old Girling springs there should be three blobs/ strips of colour paints, this denotes the spring poundage. There were, in effect , hundreds of them in an old Girling catalogue as they made shocks for every bike on the Globe at one time.
The two outer colours are the same and are called the “primary” colour the inner colour is the “secondary” colour, Hagon continued this colour springs to my knowledge;

http://www.vintagebritishcables.com/GIR ... 958-75.php

I am pretty sure the Hagon shocks came with the wrong springs: there is a ton of preload on the lowest adjustment position, and coils are heavier than the stock springs. Does anybody know if Hagon sells springs separately?
Stephen Hill

Matt Spencer said:

The only adjustment n old Girlings is Pre Load - Thus ride hight .

Click to expand...

A lot of people don't seem to realize this. Preload only affects ride height. It can be a useful adjustment to overcome bottoming out or topping out. If neither of these are happening, it has no affect on the ride stiffness and only changes the ride height.

There are two things that will really affect the stiffness of the spring;

* The total length of wire in the effective coils (mean coil diameter x pi x number of effective coils) is inversely proportional to spring rate. Longer wire, softer spring.

* The wire diameter affects spring rate to its fourth power. Double the wire diameter, 16 times a stiff.

Hi Stephen

Hagon can supply all their springs separately.

Chris

Chris said:

Hi Stephen

Hagon can supply all their springs separately.

Chris

Click to expand...

And they will advise on the right spring for your specifc application.....be specific about your weight, bike loading and riding style....should get you closer to where you need to be....

X-files said: "Preload only affects ride height. It can be a useful adjustment to overcome bottoming out or topping out. If neither of these are happening, it has no affect on the ride stiffness and only changes the ride height."

In my case there is an excess of preload so the shock is in a zero sag situation when riding the bike. The shock does not react to small bumps, making the bike ride harsh. In addition, the spring rate is too high, making the ride even worse.

Stephen Hill

Stephen Hill said:

Anybody else run into this problem? Any simple solutions? I have a gunnysack of old Girling shocks but it looks like they are all the same length. Anybody had any success shortening a spring using heat or by chopping it? There is a shroud on the shock so the mod would be hidden.

Stephen Hill

Click to expand...

Don't shorten the spring by chopping it, that will increase its spring rate and won't help at all. I doubt if heating it will help, it would be too unpredictable.
If Hagon sell springs separately that would be the way to go, or swap them for a better shock , maybe an Ikon.

Stephen Hill said:

I have a gunnysack of old Girling shocks but it looks like they are all the same length. Anybody had any success shortening a spring using heat or by chopping it? There is a shroud on the shock so the mod would be hidden.

Click to expand...

Any spring maker should be able to shorten the springs, and compress them to a shorter free length.
It doesn't take much temperature. Heating them red hot would destroy them.

You could give it a go with your kitchen oven. You'll need to compress the spring some when you do it. A piece of pipe through the centre would support it straight. Heat it to 450 fahrenheit, and let it soak long enough to reach oven temperature. If it doesn't shorten enough, compress it more and try again.