This BSA Thunderbolt has undergone extensive upgrades and modifications during the past 8-10 years of ownership, including a comprehensive engine rebuild by T&L Engineering. It’s a good starter and runner and has been used regularly, including on continental trips both single and two-up, having completed the North of Spain and Colombres Rallies in 2021.

The bike is a matching numbers 1971 Thunderbolt (single carb) Oil in Frame model, which is considered the best of all the models, with all the engine developments such as thicker barrel base and Spitfire cam incorporated. The front end has been significantly changed from the original, with the latest model Royal Enfield 41mm stanchions, a fork brace, and a Brembo single disc. It has alloy yokes converted to AV bar mounting. The bike is fitted with the last model Triumph TSS tank and modified Triumph side panels plus a Bonneville chrome rack.

This bike is built to be used, and therein lies its true value. It would cost someone the purchase price quoted to modify and update a standard A65 to this state. The price is somewhat negotiable, and payment can be made in cash or direct bank transfer. The seller has put a new MOT on it, although it’s a registered historic vehicle, so that’s not necessary.

The engine has been rebuilt with several upgrades and modifications, including a ground crank that is dynamically balanced, a timing side bush conversion with a line-bored new main bearing, and new 9.25:1 pistons and Harris conrods. The bike also has new exhaust valves (GS Valves), all new guides, new exhaust seats, and a helicoiled cover screw position. It has a new triplex chain, a rebuilt clutch with a 7-plate conversion, an SRM cover plate and actuator, and an SRM hydraulic clutch mechanism. Other modifications include an SRM oil pump and pressure relief valve, a 520 X Ring chain conversion, a Pazon ignition, a solid-state regulator, and a recent new Motobatt battery.

The bike features modern Royal Enfield front end components, such as 41mm forks, a brace, an alloy wheel rim, a Brembo brake, a stainless hose, and EBC FF pads. The alloy yokes have been converted to AV mount bars. The rear wheel has a blasted and powder-coated hub, stainless spokes, a WM3 alloy flangeless rim, and a new Avon roadrider tyre. The bike also has a chrome T140 rack, a stainless rear mudguard, a Triumph alloy tail light unit, and a new professionally chromed chainguard (not Indian chrome). The bike is also equipped with Hagon adjustable shocks, a B50 folding kickstart, a remote oil filter, and a Triumph late-model (TSS-Tiger) tank and side panels painted Ka Flame Orange metallic.

The seller is willing to answer any questions about the bike.

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eBay item number: 195665266750