Motorcycle suspension parts, on the machines this shop deals in, are far more often a substitution than an adjustment. People rarely write to us about sag or damping settings; they write because they want a different fork on the front, a longer arm at the back, or a shock that suits what the bike has already become.
Motorcycle suspension parts are a substitution question here, not a settings question
Most of what is written about the subject assumes one machine with adjustable units that are staying on it. That is fair for a modern sports bike and poor for a Monkey, a Dax, a Wave or an SR being built. If you want the theory of preload and rebound, the encyclopaedias do it well.
Our own trading history points elsewhere. The suspension entries in our archive are almost all whole assemblies rather than tweaks: fork kits, upside-down fork kits, swingarms described by how much longer they are, and rear shocks listed in street and racing versions of one item. This is the corner of our motorcycle parts catalogue where the customer already knows they are changing something and needs to know what else changes with it.
What kind of suspension job is this
The most useful thing we can do before quoting is work out the scale of the job. A weeping seal and a complete front-end change are both suspension work and nothing else about them is alike. The table sets out the scale, what each job drags behind it, and what we need to price it. It is not a fitment chart, and we do not publish one, as our 4Mini parts page explains.
| What you are doing | Typical trigger | What it takes with it | Decided first | What we need to quote it |
|---|---|---|---|---|
| Replacing a seal or a bush | It is weeping, or it knocks | The dust seal and the rubbers around it | Nothing | Frame number and a photograph of the leak |
| Replacing a shock like for like | Worn out, or the machine has stood for years | Usually nothing at all | Whether you want the road version or the competition version | Frame number, and which of the two it had |
| Fitting a different shock | The machine sits wrong, or is being built | Possibly nothing, possibly a great deal, depending what else has changed | Whether the swingarm is standard | Frame number, and what is on the bike now |
| Fitting a longer or wider swingarm | Stance, or a wider tyre | Shock length, chain length, and the guard | What the machine is being built for | Frame number, and what shock is fitted |
| Fitting different forks | Stance, a wheel change, or a front brake change | Wheel, brake, speedometer drive, cables and lines. The largest job on this list | Front wheel size, before anything else | Frame number, front wheel size, photographs of the whole front end |
| Rebuilding the steering head | It notches, or the machine has been apart | The bearing set and the year-specific parts around it | Which year the machine is | Frame number, which on some models splits the part in two |
Changing the forks is not buying a pair of forks
The clearest evidence for that is our own. The archived front-end kit for the Zoomer was not sold as forks; it was written out as a bill of nine items, because that is what the job needed. Forks, both wheels, a caliper and pad set, a disc and its bolts, the speedometer drive, a master cylinder and lever, a wheel collar kit, a longer cable and a brake line all sat in one listing.
Roughly half of that is brake work, which belongs on our motorcycle brake parts page, and the wheel half sits with wheel parts. We name the contents to show the shape of the job, not as a recipe to copy. A kit assembled for one machine years ago is not a fitment claim about yours.
There is a structural point behind the upside-down forks our archive listed as USD kits. Astemo, a Japanese manufacturer of motorcycle suspension, describes its own inverted telescopic front fork as having the outer tube above and the inner tube below, giving a rigid structure that produces a consistent damping force. That is a different architecture, not a styling choice, which is why a USD conversion is a front-end decision.
Swingarms are sold as a difference, and shocks come in two tempers
Our swingarm entries were never named after a model alone. They were named after the change: a plus-two centimetre wide type, a plus-six booster arm, a plus-two in black. The product is the difference, which tells you something the catalogues do not: buyers are altering geometry deliberately, and a longer arm changes what shock length the machine then wants.
Rear shocks divide the same way our bodywork does. Our archive listed a street shock and a racing shock as two separate items for the same machine, from the YSS range, and the choice between them was a real one rather than a grade. We publish nothing about that manufacturer beyond the fact that our own historical listings carried its street and racing shocks.
What actually fails is usually a seal, and the year usually splits the part
Before you price a fork, check whether you need a fork. Dust seals, dust rubbers, fork covers, top caps, fork bolts, swingarm bushes and swingarm seals appear across our listings for two families of machine, and a weeping leg very often wants the cheapest of them.
The other trap is the model year. On the SR the steering ball assembly was listed as two distinct items, early and late, and the top bridge bolt split at the same point. A model name cannot settle that, which is why we ask for the frame number and keep a page on identifying a part by frame number.
Questions we are asked about suspension
Can you tell me if these forks will fit my bike?
Not from a model name, and we will not guess. Fork kits in this class were often specified by front wheel size rather than by machine, and parts crossed between models routinely in builders’ hands. Send the frame number, the front wheel size and photographs of the front end, and we will say what we can source and what we cannot confirm.
What is a shock-up?
It is the rear shock absorber. The term is used across Thailand and in Japanese-English catalogues, including our own older listings, and it is worth knowing because it finds stock that “rear shock” does not. Written as shockup, it means the same thing.
Should suspension come before the rest of a build?
It depends what else is planned. A fork change decides the front wheel and the front brake, so doing it late means undoing decisions. A swingarm decides the shock and the chain, so settle it with sprocket and chain choices in view.
Sending us the details for a suspension quotation
Give us the part number where you have one, or the part name with the frame number where you do not, plus the destination country and how many you want. Where the forks are changing, add the front wheel size and what is already fitted. Photographs of the whole end you are working on help, because we can often read the answer off the picture.
Send that through the suspension quotation form and we will check the supply source in Thailand or Japan and price it in Thai Baht with shipping to your country.