Suspension question

[belgiangoth]

The weirdest thing for me on the speedmachine is the suspension. I know nothing about suspension and would like to reduce the effect it has. I'm about 70kg. There's front fork suspension and a rear thing, is there a way to reduce it so that I bounce about less? I think it is currently underdamped.

[Brucey]

on all but the smoothest surfaces you will probably be faster on a machine with suspension than without it. Fastest of all if you pedal smoothly and have dampers.

I don't know the speedmachine suspension in particular but I find it hard to believe that there are no dampers and no provision for them either.

cheers

[Cunobelin]

Post a photo of the rear unit as there are several.

If it is a sprung version, there is a large "nut" at the end of the spring, and the "column" is threaded



Turning the "nut" will release or compress the spring, altering the level of "bounce"

[Cunobelin]

There are full details in the manual available here

[belgiangoth]

Compressing Spring = less bouncy, yes?

[[XAP]Bob]

Compressed Spring should be a 'higher' starting point, and less travel.

Not strictly more damped, but it will be less movement and feel less bouncy

[Brucey]

it depends; if the attitude of the rear swingarm is changed (by adding more spring preload), chain tension variations may produce more 'bobbing' than before.

FWIW the rear suspension appears to include a hydraulic damper and the front suspension appears to include a friction damper. The owner's manual explains how to test the rear damper but it isn't clear that either damper is adjustable per se.

If the machine has done very many miles the suspension may need an overhaul anyway. It is certainly worth checking that the springs are the correct rating for the intended rider weight.

FWIW it looks as if you may be able to 'moultonise' your front suspension by adding a rubber piece inside the coil spring. Although the temperature variation in the damping/springing will be considerable, you will at least get a favourable variation in the damping between bump and rebound, which is both desirable and usually absent in friction systems.

cheers

[hercule]

Quite coincidentally I have been thinking of fitting a Suntour Epicon rear shock to my Nazca Fuego. It's done a fair few miles (before I got it!) and I've not been convinced that the rear suspension does very much. The Suntour shock might add a bit of plushness and save a bit of weight too. I have a Cane Creek air shock on my BikeE and after servicing it (mostly replacing the seals and liberally smearing everything in silicone grease) they are very effective.

This blogger seems to think they are OK. There are some lukewarm MTB reviews but I'm not going to be using it for downhill racing (not off road, anyway...)

I'd be interested in adding front suspension to my Fuego (perhaps using something like the Challenge suspension fork) but that's not going to save any weight!

[belgiangoth]

If the machine has done very many miles the suspension may need an overhaul anyway. It is certainly worth checking that the springs are the correct rating for the intended rider weight.

Ah, so it is variable by rider weight. Is there a general guideline or does it depend based on manufacturer/model?

[NUKe]

If you have the open spring model ,there are 3 different springs,you may need a lighter one, or thedamping may be shot. You adjust the preload as per the speed machine manual. If you have the gas shock you will need a shock pump.your preload shhould allow about 30%sag with you and luggage.

[Cunobelin]

All you need to know is in the manual linked earlier

[RecumbentRide]

Quite coincidentally I have been thinking of fitting a Suntour Epicon rear shock to my Nazca Fuego. It's done a fair few miles (before I got it!) and I've not been convinced that the rear suspension does very much. The Suntour shock might add a bit of plushness and save a bit of weight too. I have a Cane Creek air shock on my BikeE and after servicing it (mostly replacing the seals and liberally smearing everything in silicone grease) they are very effective.

This blogger seems to think they are OK. There are some lukewarm MTB reviews but I'm not going to be using it for downhill racing (not off road, anyway...)

I'd be interested in adding front suspension to my Fuego (perhaps using something like the Challenge suspension fork) but that's not going to save any weight!

That's funny I was just thinking of swapping out the air shock from my Bike E AT (Cane Creek AD-5 I believe) to my Optima Stinger just to see how the ride quality is affected. The existing coil shock on the Stinger is alright but I'm hoping to try and get a softer ride if possible. Additionally I like the idea of being able to alter the give on the go unlike the coil shock where if there is a drastic weight change i.e. from day riding to touring, it would involve swapping out the coil. I might even chance the coil shock on the Bike E!
The alternative would be to find a new air shock to replace the coil spring but I'm wondering how accurate you would have to be to with the shocks eye to eye measurement and could I get away with a slightly longer shock, hmmm.
I previously had a Grasshopper which was fully sus, built like a tank and a great tourer but maybe a bit heavy. I do miss the front sus forks but I get the feeling the stinger is faster, but I could be wrong it's been a while.

[NUKe]

Are all gas rear shocks the same?

I don't really mean that, but are they as interchangeable as say tyres. And what to do I need to determine for one to fit my Grasshopper ?

[RecumbentRide]

Are all gas rear shocks the same?

I don't really mean that, but are they as interchangeable as say tyres. And what to do I need to determine for one to fit my Grasshopper ?

I believe they have been standardised across various categories but I don't know enough about this to advise so have a look here http://hub.chainreactioncycles.com/buying-guides/components/rear-shocks-buying-guide/

[Brucey]

there are several different lengths, strokes, and end fitting dimensions. Whilst you can often make a shock absorber fit OK, it may not have the correct damping rate in it, or indeed have the required range of adjustment, eg because the wheel load and the motion ratio of the linkage working the shock is different from that intended.

BTW 'a gas shock' would be one with a gas charged damper assembly. Many bicycle shock absorbers are 'air shocks' which means that the spring element is an air spring. Not all gas shocks are air shocks and vice versa.

cheers