Adhesives,

Aluminium,

Ball & Socket Joints,

Batteries,
Battery Chargers,

 Bearings,

Belts (Drive),

Belt Pulleys,

Brakes,

Chain(Roller),
Chain Sprockets,

Drill Bits,

Electric Motors,

Hose Clips,

Motor Controllers,

Electric Cables Switches etc,
Fasteners,

Gears,

Screw Taps & Dies,

Shaft Clamps & Couplings,

Springs,

Steel,

Timber,
Hand & Bench Tools,

Wheels,

Miscellaneous Links

Bearing Boys

OnlineBearings.co.uk

RS Components For research 1st check the Loctite web site

Try Chronos Engineering Supplies for  Delta adhesives.

ModelFixings.co.uk for Zap & other Adhesives - low cost alternative to Loctite range

SmallParts, Inc  For research 1st check the Loctite web site

Grainger

McMaster-Carr Supply Company

Metals4u - wide range

MetalsSupermarkets for local pickup
Chronos Engineering Supplies Short lengths
Folkestone Engineering Supplies
CES

Technobots   Sheet and Plate

SmallParts, Inc

McMaster-Carr Supply Company

New England Brass and Tool

Ball & Socket Joints

Bearing Boys

RSComponents
Ondrives

mbo-Osswald

SmallParts, Inc
McMaster-Carr Supply Company

Batteries (Heavy Duty Rechargeable)

Maplin Electronics Ltd

DiscountScooters.co.uk

SunShineSolar

Active-Robots for Odyssey Lead Acids & others

Battery Megastore
RS Components
MDS Battery 

Easycads.com

Also check on eBay.co.uk - Click here! Search for "Mobility Battery"

PartsForScooters

NPC Robotics
McMaster-Carr Supply Company
ElectricScooterParts.com
MonsterScooterParts

EVParts.com

The RobotMarketPlace

Battery Chargers

Battery Megastore

MachineMart
MDS Battery

McMaster-Carr SupplyCompany
NPCRobotics
ElectricScooterParts.com

 MonsterScooterParts

The RobotMarketPlace

Bearings (Roller & Plain)

Bearing Boys

Marchant Dice for linear bearings

OnlineBearings.co.uk

MotionCo

The BearingShopUk

Technobots  inexpensive needle roller.
RS Components
Ondrives plain and roller.
Arc Euro Trade For some imperial sizes.
Simply Bearings

ModelFixings.co.uk for ball bearings and over-running clutches.

SmallParts, Inc
SDP-SI Sterling Instruments inlcuding both metric and imperial sizes
Grainger
McMaster-Carr Supply Company
VXB.com Bearings including metric needle rollers

The BIG Bearing Store

Bearing Boys

Beltingonline

OnlineBearings.co.uk

MotionCo

Cross & Morse

Davall Stock Gears
HPC Gears
RS Components

SmallParts, Inc
SDP-SI Sterling Instruments
Grainger
McMaster-Carr Supply Company
 ElectricScooterParts.com

The RobotMarketPlace

Bearing Boys

Beltingonline

OnlineBearings.co.uk

MotionCo

Cross & Morse

Davall Stock Gears
HPC Gears
RS Components
Farnell

SmallParts, Inc
SDP-SI Sterling Instruments
Grainger
McMaster-Carr Supply Company

The RobotMarketPlace

Brakes

A number of UK online scooter style brake suppliers have disappeared recently, your best bet may be to try ebay for electric scooter or mini-moto spares

Try bike parts for disc brakes eg ChainReactionCycles

PartsForScooters

ElectricScooterParts.com
 MonsterScooterParts

Chain (Drive)

Bearing Boys

OnlineBearings.co.uk

Cross & Morse

RS Components
Technobots

PartsForScooters

SmallParts, Inc
SDP-SI Sterling Instruments
Grainger
McMaster-Carr SupplyCompany
ElectricScooterParts.com
SDScooters

 MonsterScooterParts

The BIG Bearing Store

The RobotMarketPlace

Bearing Boys

OnlineBearings.co.uk

Cross & Morse (one of the least expensive sprocket supplier I've found, no US sprockets though - order by phone £10 min order chg.)

Technobots
RS Components
Farnell
HPC Gears

PartsForScooters

SmallParts, Inc
SDP-SI Sterling Instruments
Grainger
McMaster-Carr Supply Company
MonsterScooterParts

The RobotMarketPlace

Drill Bits

PetrolScooter UK

  It is also worth checking eBay for scooter motors.

Active-Robots for powerful Magmotors and smaller robot gearmotors

For Unite motors imported from US try TNCScooters - can be a surprisingly inexpensive option if you can wait a couple of weeks!

Try also Ebay imports from US sellers

Technobots  Some small motors only.

PartsForScooters

TNCScooters

SDScooters

EVParts.com
NPCRobotics
ScooterSupport.com
SurplusCenter (large range of other items also)
Electric Vehicles USA

ElectricScooterParts.com

Try Also Ebay

MonsterScooterParts

The RobotMarketPlace

Electric Motor Controllers

4QD - very informative site.

Technobots   good range with various current capabilities..
 Devantech Ltd - robots electronics site with range of equipment including smaller H-Bridge speed controllers.

Active-Robots for range of controllers

CurticeInstruments
NPCRobotics

EVParts.com
Electric Vehicles USA
(for motors and controller accessories also)

Superdroidrobots

The RobotMarketPlace

Electric Cables, Switches etc

Maplin Electronics Ltd

Technobots
4QD
 

CableOrganizer.com

EVParts.com

Check local suppliers

The RobotMarketPlace

 Fasteners (Nuts, Bolts & Screws)

Technobots

Westfield Fasteners

GWR Fasteners
RS Components
Ondrives
ModelFixings.co.uk

A2A4 Fixings - Stainless Steel Fasteners

Microfasteners includes metric sizes
SmallParts, Inc
SDP-SI Sterling Instruments
Grainger
McMaster-Carr Supply Company

Bolt Depot

Beltingonline

Bearing Boys

Technobots

Davall Stock Gears

HPC Gears
RS Components
Farnell

RushGears includes metric sizes
QTCGears includes metric sizes
SmallParts, Inc
SDP-SI SterlingInstruments
Grainger
McMaster-Carr Supply Company

The RobotMarketPlace

For a range of planetary gearheads see -

AutomationDirect.com

(Try local DIY store in plumbing sections)

OnlineBearings.co.uk

The BearingBoys

Wickes

B&Q

Westfield Fasteners

Screw Taps & Dies

Chronos Engineering Supplies
Maidstone Engineering Supplies

ModelFixings.co.uk

 Shaft Clamps & Couplings

Bearing Boys

OnlineBearings.co.uk

RS Components for Ruland Clamps
Ondrives

The BIG Bearing Store

Ruland (You'll need local distributor)
ClimaxMetal Products
SDP-SI SterlingInstruments
Grainger
McMaster-Carr Supply Company

The RobotMarketPlace

Springs  

Bearing Boys

SpringMasters

Ondrives
Lee Spring
 StrutsDirect.co.uk

Aluminium 2 Buy (for tube)

Marchant Dice for linear guide rods

MetalsSupermarkets for local pickup
Chronos Engineering Supplies Short lengths
Folkestone Engineering Supplies
CES
Ondrives for longer lengths of bright shafting. 
Check local stockholders also.

Technobots   Sheet and Plate

Mallard Metals

SmallParts, Inc
McMaster-Carr Supply Company
Manufacturer's Supply
New England Brass and Tool

The RobotMarketPlace

Wickes

B&Q

for both plywood and planed (dressed) timber

Bearing Boys

Wickes

Maplin Electronics Ltd

Chronos Engineering Supplies
MachineMart
ArcEuro Trade
ChesterUK Ltd

Toolsnstuff

CableOrganizer.com

SmallParts, Inc
McMaster-Carr SupplyCompany
New England Brass and Tool

...and a directory

ThomasNet

 Wheels

Pneumatic, Spoked and others

US maker Worksman will also supply to the UK. Email them.

For spoked wheels & parts
Unicycle.com (uk)
Billys (for BMX & other bike wheels)

Gemini Karts for chunky pneumatic wheels

Technobots

Northern Tool Equipment

PartsForScooters

McMaster-Carr Supply Company
NPC Robotics
ElectricScooterParts.com
Manufacturer's Supply
CasterSupply.com
Worksman (for heavy duty spoked trike wheels)

The RobotMarketPlace

s3i Stainless Steel Solutions  For wire rope/cable & a good range of fittings

MarineStore Chandlers Rope & cable pulleys & sheaves