1 PC Handlebar Switch. Stainless steel bolts clamp it to any handle bar. Push buttons are water proof and vibration resistant. Universal for 7/8" bar. Buttons are IP65 protection rated against water ingress.
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5/20/100Pcs 7mm Push Button Switch PBS-110/111 Momentary ON-OFF Micro Switch NO NC Reset Switch
Aliexpress UK
1" 7/8" Handlebar Custom Vintage Cafe Racer Push Switch Gear Housing Dual Button Momentary 2 Buttons for Harley XS650 Honda Specification： Condition: 100% brand new Switch Housing Material: CNC 6063-T6 aluminum alloy The casing Color: Black / Chrome Button Color: Black / Chrome Inner diameter: 25.4mm (1in.) and 22.2mm (7/8in.) Waterproof Ip Rating: IP65 Switch Lifespan: 200,000 times Power:120W(max) Current:10A Voltage:12V Working mode: One product with 2 buttons (momentary switches, like a horn) Package included: 2 x Handlebar Switch Installation instruction not included Fitment: Universal for 1″ or 7/8″ motorcycle handlebars Suitable for most 12V battery installation motorcycles, cafe racer, scooter. etc.
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2 4 Way position Monolever switch joystick 30mm Toggle Joystick Rocker Cross Switches Reset Momentary Self Latching switch HNT
Aliexpress UK
Mini handlebar switch block ,plastic-coated toggle switch. Suitable for lights, indicators, horn, starter, kill switch, etc. Switch block body measures 41mm long x 18mm wide x 14mm high. Eliminate the need for your stock switch blocks. These mini switches have a contoured base designed to sit flush on 7/8" or 1" handlebars. Easy to install. Requires the drilling of 2 holes - a 15mm diameter hole for the toggle switch, and a 9mm hole for the push button switch. Note: a 3.3mm hole needs to be drilled and tapped with an M4 tap to create threads for the supplied M4 screw which fastens the switch to the bar.（M4 screw not included in package) All the associated wiring can be routed through the handlebar to an exit point of your choosing. The button is a "push-on" momentary typ.
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20/50/100Pcs Micro Tactile Switch Momentary Tact DIP Switch 2Pin 6 x 6mm Micro Touch Push Button Switch High 5mm 6mm 7mm 8mm 9mm
Aliexpress UK
Features: Size:7/8'' Material：Aluminum Dual / 2 Button Microswitch Hand Control Momentary Switch Custom Switch Gear Housing Package Included: 1 pc switch Fitment: For 22mm handlebar Custom switch gear housing and dual momentary buttons for low profile custom look. For a Single M-Switch Housing for 7/8''Handlebars.
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10Pcs Micro Limit Switch Momentary Push Button Switch 1A 125V AC Mouse Switch 3Pins Long Handle Roller Lever Arm SPDT 12X6X6MM
Aliexpress UK
& Relay is only need if using as a starter button (I've used it on my CB750KZ without a relay and had no problems but it's advised to use one on high current circuits) If you require it to latch i.e high/low beam / indicator then you will need a relay to do this.
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10pcs Micro Switches Miniature Small Limit Travel Switch With Hole Three Pins Momentary Push Buttonopen Switch DIY Production
Aliexpress UK
7" Flexible Air Tyre Valve Extension Adaptor Motorcycle Car Tire Stem Extender u. Mini LED Lighting Finger Board Colorful Skateboard Kids Children Toy Kid Gifts V. Self-lock Reset button can be used as horn, engine power, start kill switches.
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22mm SCV4-YQ-05R2G / SCV4-YQ-04R2G Cross Switch 4 Direction Main Switch Knob Button 360 Degree Momentary Monolever Switch
Aliexpress UK
Fitment: Universal for 1" bar Package Included: Handlebar Switch.
eBay
1PCS V-156-1C25 15A The micro switch, Push Button SPDT Momentary Snap Action Limit switch, travel switch
Aliexpress UK
Mini handlebar switch block with black, plastic-coated toggle switch. Suitable for lights, indicators, horn, starter, kill switch, etc. Switch block body measures 41mm long x 18mm wide x 14mm high. Eliminate the need for your stock switch blocks. These mini switches have a contoured base designed to sit flush on 7/8" or 1" handlebars. Easy to install. Requires the drilling of 2 holes - a 15mm diameter hole for the toggle switch, and a 9mm hole for the push button switch. Note: a 3.3mm hole needs to be drilled and tapped with an M4 tap to create threads for the supplied M4 screw which fastens the switch to the bar.（M4 screw not included in package) All the associated wiring can be routed through the handlebar to an exit point of your choosing. The button is a "push-on" momentary typ.
eBay
25PCS Tactile Push Button Switch Momentary 12*12*7.3MM Micro switch button + 25PCS Tact Cap(5 colors) for Arduino Switch
Aliexpress UK