Triumph T120 Bonneville & TR6 · 1963–1970

The restoration reference for Triumph's unit 650 twins

Unit 650 puts the factory's parts books, workshop manuals and owner's handbooks in one place and links them part by part. Step-by-step guides take you through the engine from teardown to rebuild. It was built by a restorer for restorers, and it works on your computer, tablet or phone at the bench.

Testing now. A small group of riders is testing Unit 650. Subscriptions open when testing ends. If you'd like to be told when that happens, email askmike@unit650.com.

What's inside

Parts books, linkedThe factory parts catalogues for the unit 650s, UK and USA editions. Every figure is linked to its parts, with part numbers, quantities and the year differences.
Manuals and handbooks at the right pageEach part opens the workshop manual and owner's handbook at the page that covers it. You read the factory's own words, with their printed page numbers.
Engine teardown and rebuildStage-by-stage guides with a picture for every step. Each step gives the factory's figures, what to inspect and what goes wrong.
Specifications and serviceSettings, capacities and service schedules for each year and model, with the source page for every figure.
Electrics, fasteners and forksWiring diagrams and upgrade notes, fastener tables by thread and year, and a chart of what fits where on the triple trees.
A library of the original documentsService bulletins, technical articles and period papers in high-resolution scans, searchable and cited by title and page.

A sample entry

Part	Cylinder base nut
Year	1968
Number	37-0076
Thread	3/8 in. CEI, 26 tpi, reduced hex

Price

Monthly or yearly subscription, in US dollars (USD)

The monthly and yearly prices will be shown here before subscriptions open. You'll see the full price before you pay. Any sales tax or VAT that applies where you live is worked out at checkout and shown before you confirm.

Unit 650 is delivered online. Your subscription starts as soon as your payment goes through, and nothing is shipped.

Cancellation and refunds

You can cancel at any time. Cancel from your account page or by emailing askmike@unit650.com. You keep access until the end of the period you have paid for, and you won't be charged again.

14-day refund. If Unit 650 isn't what you expected, email within 14 days of your first payment and you'll get a full refund. After that, payments already made are not refunded, but you can always stop the next one by cancelling.

Contact

Questions about Unit 650, your subscription or a refund go to Mike by email:

askmike@unit650.com

Mike reads every message and replies himself.

Privacy

Unit 650 keeps as little about you as it can. When you subscribe, we keep your name, your email address and whether your subscription is active, so that you can sign in.

Payments are handled by Stripe. Your card details go straight to Stripe and never reach or stay on this site. We don't sell or share your details, and we don't use advertising or tracking cookies. Notes you make in the reference are kept in your own browser.

To see or delete what we hold about you, email askmike@unit650.com.

Terms of use

A subscription is for your own personal use. Please don't copy, share or republish the reference or its documents.

The original documents remain the property of their owners. They are included for reference.

Unit 650 is a guide, not a guarantee. Check figures against the factory documents it links to, and work on your motorcycle at your own risk.

Unit 650 is independent. It is not connected with, or endorsed by, Triumph Motorcycles Ltd. Triumph, Bonneville and TR6 are trademarks of their owners.

These terms are governed by the laws of California, USA. If they change, the new version will be posted on this page.

Security

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