Tech Blog

Welcome to the Technical Information Blog dedicated to the fun and always fascinating world of vintage Triumph, Norton, and BSA motorcycle parts. This blog serves as a comprehensive resource for enthusiasts and collectors who are passionate about these iconic British motorcycle brands.
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Our Most Recent Tech Blogs
A Look at the Lucas 149SA and 47SA Ignition Switches
Lucas 149SA 47SA Ignition Switches Ignition Switches47SA 3-Position Ignition Switch149SA 4-Position Ignition Switch The Takeaway The Lucas 3 and 4-position ignition switches…
Matchless AJS and Associated Motor Cycles
Dave Porter, Customer Service and Tech Support AMC Looking back on some of the more revered names in the annals of…
The Conundrum of Triumph C-Range Top-End Compatibility
Triumph T100 Top End – The Conundrum of Triumph C-Range Top-End Compatibility Unfortunately, I have chosen to take on a…
Timing Tri-Spark Ignition – Classic Twin Ignition
…setting the timing. The Classic Twin Ignition is suitable for Triumph Unit Twins T100, T120, TR7RV, T140 Bonneville, Tiger, Daytona…
A Word About BSA, Norton, and Triumph Seat Supply
If you have been searching for seat supply for your vintage British motorcycle as of late, you may find…
A Look at the Mysterious Lucas Cutout/ Lucas Kill Switches
Lucas Kill Switches and Cutouts 4A Cutout – Kill Switch: 762080, 76200A, and 762204SS5 – Lucas Kill Switch: 31071, 31376SS5 -…
Norton Motorcycle Photos
Norton motorcycle photos from our customers here at The Bonneville Shop. Check out or stock of parts for your Norton….
Gearbox Sprocket: Tips for a Grooved High Gear Spine and Chamfered Sprocket
From Guest Expert: Don Johnson To use an o ring with the gearbox sprocket you must have a high gear spline…
The Imperiled Life of the Kickstarter Cotter Pin
…lever to rotate slightly on the spindle, effectively reducing the amount of sweep the lever moves on the downstroke.” One…
Year, Make, Model – What Are You Working on Today?
Triumph and BSA Frame and Engine NumbersWhere are the Frame and Engine Numbers?Registration and Title Documents for Year Make Model …
Setting Up Dual Carbs
…to slow down, then turn it out until the engine starts to slow down-set the mixture screw half way between…
A Guide To Triumph Headlamp Shells
By Dave Porter, Customer and Technical Support at The Bonneville Shop Table of Contents for Triumph Headlamp ShellsLucas SS 700 7”Lucas…
Amal Carb Fitment: An Everyman’s Guide
It’s been said many times that nothing wakes up an old British motorcycle like a new carburetor. Amal carb…
A Bit About Fender Stays
A Bit About Fender Stays “…there are many different configurations of fender stays to be considered when selecting the correct…
Why Not A BSA?
Dave Porter, Customer and Tech Support at The Bonneville Shop Barn Bikes Abound – BSA Motorcycles “…not only are they plentiful, but…
The Case for the Parts Catalog as the Most Important Tool in the Cabinet
Dave Porter, Customer and Tech Support at The Bonneville Shop Work Smarter, Not HarderAdvantages to a Printed Parts CatalogParts Catalog Selection Parts…
TECH TIP: How to Install New Clutch Rubbers
Dave Porter, Customer and Tech Support at The Bonneville Shop Steps to Install New Clutch RubbersUsing a Clutch Locking ToolThe Disassembled…
Sealing Washers and the Oil-Tight Triumph Engine
‘Sealing Washers and the Oil-Tight Triumph Engine’ by Dave Porter, Customer and Tech Support at The Bonneville Shop Fiber WashersCopper WashersStat-O-Seal…
Application Techniques for Waterslide Decals
Dave Porter, Customer and Tech Support at The Bonneville Shop There are 4 basic steps on how to apply a waterslide…
Motorcycle Fender – Classic Triumph Fender – OEM and Custom Mudguards for Your Project Bike
A motorcycle fender will restore your classic Triumph to its true glory. Don’t put an old, compromised fender on your…
Triumph Service Bulletin Twin 9-70: Rotor/Rotor Nut
Loose Rotor Nut or Rotr Center: Triumph Service Bulletin Twin 9-70 Dave Porter, Customer and Tech Support at The Bonneville…
Winterizing Your Classic Brit Bike Checklist
…by the time the bike will start, it’s Sunday night and forty degrees out, with the weekend in the rear-view…
The Nuts and Bolts of Hardware
The Nuts and Bolts of Hardware By Dave Porter, Customer and Technical Support at The Bonneville Shop “…a factory parts catalog is…
How To Convert Your 6-Volt British Motorcycle to 12-Volts
By Dave Porter, Customer and Technical Support at The Bonneville Shop Converting Your 6-volt British Motorcycle to 12-volts can be a…
Get ‘em While They’re Hot- 130 Link 530 Chains!
130 Link 530 Chains By Dave Porter, Customer and Technical Support at The Bonneville Shop We recently procured a substantial quantity of…
VIDEO: Motorcycle Polish: Tips for Your Primary and Timing Cover
Motorcycle polish: yes or no? Did you just get your hands on a solid barn bike? How long was it…
Considerations for Your Brit Bike: A Brief Guide to Cables
…a factory original Amal 364. This difference can alter the desired inner wire free length downstream at the carburetor’s throttle…
Bearing Race Puller – Motorcycle Tools
Buy a bearing race puller today. If you’re doing any motorcycle restoration, having the right tools is essential. Bearings, including…
Fork Damper Sleeve Install – Which Way Do They Go?
– For Triumph and BSA forks up to 1970 (up to 1974 on the Triumph 500 twins and some of the…
Triumph Top-End Sealing and What the Workshop Manual Doesn’t Explain
By Dave Porter, Customer and Technical Support at The Bonneville Shop Table of Contents for triumph top end sealingResourcesConsiderations For…
A Primary Concern: The B-Range Chaincase Covers
By Dave Porter, Customer and Technical Support at The Bonneville Shop Primary Chaincase Cover: 57-1727 Primary Chaincase Cover: 57-2439 Primary Chaincase Cover: 71-7465 The…
The Importance of Right to Repair Legislation
By Mike Grage, Customer and Technical Support at The Bonneville Shop written in partnership with British Iron, our Modern Triumph…
A Guide for BSA and Triumph Oil Pressure Switch Identification
‘A Guide for BSA and Triumph Oil Pressure Switch Identification’ By Dave Porter, Customer and Technical Support at The Bonneville…
Pattern Parts and Fettling to Perfection
…times, a helper. Since reproduction fender stays are not always constructed identically to the originals, with slight variances in overall…
Using LEDs with Traditional Turn Signal and High Beam Indicator Lights
…side will solve this problem. The diodes isolate the left circuit from the right keeping all electricity supplied to the…
Dave’s Building a 10-Footer: A 1970 Triumph TR6R Build – Part 2
The 1970 Triumph TR6R Build Continues: Rotor and StatorPrimary Chaintiming cover and outer gearbox The 1970 Triumph TR6R Build Continues: Rotor…
Dave’s Building a 10-Footer: 1970 Triumph TR6R Repair – Part 1
The 4th One – 1970 Triumph TR6R RepairFinding a Barn BikeDisassemblyEvaluating the Parts and PrepWheels and forksEngine Cases, Crank and…
How the Tiger 100 Became the Triumph Daytona
Doug Hele and the Daytona1967 – 1969 Triumph DaytonaThe end of the Classic Triumph Daytona By Dave Porter, Customer and Technical…
A Farewell to Real Chrome
By Mike Grage, Customer and Technical Support at The Bonneville Shop The Chrome of Before – Real ChromeLegislative ChangesTrivalent Chrome The Chrome…
Electronic Ignition System Diagnostics
By Mike Grage, Customer and Technical Support at The Bonneville Shop Function of Electronic Ignition SystemsTesting Functionality Here at The Bonneville Shop…
Triumph Service Bulletin 64/1 – 1964 Forks – Eliminating Oil Leaks
1964 Forks – Eliminating Oil Leaks By David Porter, Customer and Technical Support at The Bonneville Shop One topic that comes up…
Easy Tri-Spark Triples Ignition Kit Installation Guide
…wire to the timing side coil’s negative (-) terminal, red wire to the middle coil’s negative (-) terminal, and white…
Tips on Fitting the Girling Stainless Floating Brake Disc Rotor
SpecsFitment ChallengesSolutions We have recently taken delivery and sold through our initial shipment of Girling’s new 37-4275G Stainless Floating Brake Disc…
Thunderbolts and Lightning: BSA Motorbikes
BSA Motorcycles: Thunderbolts and Lightning, very, very frightening me! (Galileo) Galileo (Galileo) Galileo… By David Porter, Customer and Technical Support at The…
TECH TIPS – Evaluating Your Clutch Plates and Springs
Clutch Plates AND Springs Clutch Plates When evaluating the clutch plates and springs, clean and inspect the clutch plates for…
What exactly is a 1978 Triumph Bonneville?
…Sourcing Parts History of the 1978 Triumph Bonneville As any experienced Triumph parts expert will tell you, the 1978 Triumph…
Cam Timing Notes – Part II
Checkout Cam Timing Notes Part I here and The Brain of Your Triumph B Range Engine- the Camshaft. Cam Timing ContentsCheckout Cam…
VIDEO: Dozens of UK Made OEM & Universal Fenders
…fitment. Table of Contents Stacy on Speedwell Mudguards How these UK made fenders are Measured Stacy on Speedwell Mudguards https://www.youtube.com/watch?v=oaw0E4LkteM…
Using the Degree Wheel to Establish Ignition Timing
…have finally decided to convert your 1967 Triumph Bonneville to electronic ignition. The instructions tell you to remove the points…
The Brain of Your Triumph B Range Engine- the Camshaft
…valves to produce the sequence of valvetrain function in the Triumph twin engines. In the beginning, when the first 650cc…
A Brief Synopsis of the Lucas Console Switchgear and Its Evolution
By David Porter, Customer and Technical Support at The Bonneville Shop Lucas Console Switchgear Guide The Back Story During the late 1960s, the…
12 Volt Charging System Diagnostic Guide
By Mike Grage, Customer and Technical Support at The Bonneville Shop How it Produces ElectricityStator TestingRectifier TestingRegulator Testing 12 Volt Charging System…
TECH TIPS – Layshaft Needle Bearing Installation Tool
Layshaft Needle Bearing Installation Tool By David Porter, Customer and Technical Support at The Bonneville Shop Installation InstructionsShop The Layshaft Need Bearing…
Carburetor Mounting Orings: 622/101 Thin vs 70-9711 Thick
Function of Carburetor Mounting OringsThick 244/1048 OringsThin 622/101 OringsAdditional HardwareMeasuring the Gap By David Porter, Customer and Technical Support at The…
Creating a Custom Motorcycle Cable
By David Porter, Customer and Technical Support at The Bonneville Shop Custom Motorcycle CableChoke and Throttle CablesFront Brake custom motorcycle cable Custom…
Triumph Service Bulletin 11/71 – Piston Ring Replacement
…you come up with a range of .0135-.018” for the top compression ring and oil control ring, and .0165-.021” for…
Triumph Service Bulletin 4/72 – Servicing the Hydraulic Disc Brake
By David Porter, Customer and Technical Support at The Bonneville Shop Background Service Bulletin 4/72 focused on the hydraulic disc brake and…
Tech Tip – Fettling with your Vintage Brit Bike
By David Porter, Customer and Technical Support at The Bonneville Shop Having trouble fitting Triumph parts to your vintage bike?What is…
Triumph Service Bulletin 10-69 – Amal Concentric Carbs
By David Porter, Customer and Technical Support at The Bonneville Shop BackgroundService Bulletin 10-69Amal Concentric Carbs – Parts Background On May 1, 1969,…
Why do you offer 2 Different Wiring Harnesses for my Bike?
…has all of the same connection points that were fitted to the original main harness and correct wire lengths to…