FF: Forks Fork Travel
- Thread starter Bowsh
- Start date
I cant remember if it's the Koni or the Armstrong which has the longer lower eye bolts, perhaps the Armstrong which my bike had on originally. There is the modern Icon shocker which is similar to the original Koni. The AVO made in the UK, and the Thornton from the US, possibly still available but not in production any more. Any modern shock is far better than the earlier makes/models. If your front end is a bit aggressive on the bumps you might want to see what springs you have as the bike like many others could be over sprung. It is not uncommon to find sidecar rated springs in the rear spring boxes as well. If the wire diameter is around 0.320" this will make the rear very stiff. The correct solo springs have a wire of 0.300" in diameter. Cheers...............Greg.
Bowsh, look in the rear pages of MPH and you will find an advertisement for AVO. They are happy to deal with you direct and the dampers were developed in conjunction with hadronuk, a well known club member. Your photo shows an Armstrong damper with the short eyebolts, exactly the wrong configuration.
While doing spring and damper testing for the modified steering stem I found the Armstrong to be about the same as a standard damper, certainly better than a Koni in respect of small undulations and all were about the same when hitting potholes or speed humps, if the shock was that violent I too would also suggest you check the front springs.
I have Avo dampers on my Comet and have just fitted the latest version to a friends Comet and I am very pleased with the handling of the 2 bikes.
The Armstrong seems to suit the Girdraulics very well. I have had them in all three of my Vins (Rapide and 2 Comets) for over twenty years. They have not leaked and the damping has not deteriorated in that time. They must be used with the longer eyebolts unless there is a danger of the mudguard touching the magneto cowl or even worse the front exhaust pipe if it is not quite to the original pattern. They do have a fault however. Over time the bottom mounting wears and, so far as I know, no one has come up with a way of reclaiming the original fit. Hugo.
The thing is that thoughts on dampers have moved on in the 65 years since the Armstrong dampers were specified. The Vincent damper must have been expensive to produce and was prone to leaking. (Yes I know that there are now ways round that). It probably seemed cost effective at the time to get a propriety damper to do the job but both the Vincent and Armstrong dampers have the same resistance on compression and extension. That has not been thought to be a good idea for at least 50 years to my knowledge, and I am no expert on this. The new dampers not only have different rates in the two directions but are also adjustable. I have no connection with AVOs other than as a satisfied user.
I have an AVO Damper on my Rapide and the suspension is almost to modern standards. The Girdraulic reacts to all the small bumps but never seems to bottom. With a modified original damper it was not bad either but a lot of shock was transmitted with really abrupt bumps. The AVO seems to work well for the little undulations and the really abrupt bumps. I am not sure what springs I have installed but the bike has about the right amount of sag in the suspension. I have installed oilers on various joints and I keep them all lubed. To test the suspension you have to stand on the pegs and jump up and down but not hold the brake. Pushing forward on the handlebars with the brakes locked doesn't work the same as on telescopic fork bikes. With the Girdraulic you can go over speed bumps with the brake applied that doesn't work on other bikes