Performance Review: Norton Mercury 650 - [1968]

Figures & Specs Summary:

Norton Mercury Performance Review.

Introduction:

This edition of the Norton Mercury 650 is the 4 speed | Manual version and was first brought out in 1968. This was at around the same time as the introduction of the 1969 Suzuki A 95 Two Stroke and the 1969 Suzuki T 125 II Stinger.This particular Norton Mercury has a 646cc Air cooled, Two stroke, Wankel Petrol powerplant with 2 cylinders and Carburettor.

An alternative Wankel engine, Standard style motorbike includes the Yamaha XSR 700 Twin - [2020]

The 1968 Mercury shares its Wankel engine and Standard style configuration with the likes of the 2020 Yamaha XSR 700 Twin and the 2018 Yamaha XSR 700 Twin. Alternatively, if you're looking for other bikes which share the Mercury's Standard style with a similar size of engine then how about the 2020 Yamaha XSR 700 Twin | 2020cc.2018 Yamaha XSR 700 Twin | 2018cc.

Power and Torque:

Weighing in at 0 kgs (0 lbs) this makes the Norton Mercury 650 in the same weight category as the 2025 Yamaha Tracer 9 GT+ or the 2025 Yamaha Tracer 9 GT, give or take 50kg.

The 1968 Norton Mercury shares the same bhp with the Yamaha WR 250 F - [2025]

In terms of power the 646cc 4 valve Wankel 2 cylinder engine produces 47 bhp (35 kW) @ 6800 rpm similar to the 2025 Yamaha WR 250 F [36.1 bhp (26 kW) @ 12000 rpm] or the 2025 Honda X-ADV 745 [57.8 bhp (43 kW) @ 6750 rpm].

The OHV Two stroke unit throws out torque of 36.8 lb-ft (49.9 Nm) @ 6500 rpm placing it alongside motorbikes of similar performance figures such as the 2025 Yamaha MT-07 Twin Cylinder [50.0 lb-ft (67.7 Nm) @ 6500 rpm] and the 2025 Yamaha Tenere 700 [50.2 lb-ft (68.0 Nm) @ 6500 rpm].

Power to Weight:

If one combines the weight with power or torque performance for the Norton Mercury you can get a better idea of it's real world performance.

The 2024 Kawasaki Eliminator 500 ABS SE has similar Bhp Per Ton stats as the 1968 Norton Mercury 650.

The 1968 Norton Mercury 650 has a Power to weight ratio of 229.2 bhp per ton and 179.8 lb-ft per ton. Bhp Per Ton figures of the 1968 Mercury competing with the 2024 Kawasaki Eliminator 500 ABS SE [254.2 bhp\ton] and the 2006 Yamaha XV 1700 Road Star [253.9 bhp\ton].

Power to Weight(cont.):

If you agree with the late great Carroll Shelby, then arguably an even better indicator of potential performance is Torque. Factor weight into the equation and you end up with - Torque per ton, with the Norton Mercury generating around 179.8 lb-ft per ton. If you're curious as to what other motorbikes have as much torque to weight then look no further than the 2015 Kawasaki W 800 Twin Cylinder [204.8 lb-ft per ton] and the 2011 Kawasaki W 800 Twin Cylinder [204.8 lb-ft per ton].

Acceleration:

With a 0-60mph time of 16.1 secs or a 0-100km/h (0-62mph) of 16.5 secs, this makes the Norton Mercury 650 similar in acceleration to the 2015 Honda VT 1300 CT Interstate (16.1 secs) and the 2013 Honda VT 1300 CT Interstate (16.1 secs). This Norton Mercury 650 also competes in terms of 0-60 mph and 0-100km/h with the 2018 Honda CB 250 R Neo Sports Cafe (0.0 secs) and the 2020 Norton Superlight SS (0.4 secs).

Quarter Mile time is a close race between the 1968 Norton Mercury 650 and the 1988 Honda XRV 650 Africa Twin

When talking about the performance of the 1968 Norton Mercury 650 on the drag strip it can reach a quarter mile in an estimated 0 secs @ 0 mph. Bikes with a similar performance down the quarter mile can be found in the 1988 Honda XRV 650 Africa Twin (0 secs) and the 1981 Honda CB 400 T Hawk III (0 secs).

Top Speed:

The 1968 version of the Norton Mercury 650 has a maximum speed of 0mph.

Top Speed of the 1968 Mercury equals the 2013 Honda CHF 50 Metropolitan

If maxing out your bike on the AutoBahn is your thing and you're wondering what's faster at the top end than the 1968 Norton Mercury 650 then how about a 2013 Honda CHF 50 Metropolitan (35 mph) and the 2002 Honda CHF 50 Metropolitan (35 mph).

Related Links:

1968 Norton Mercury Rivals List.

A Brief History of Norton

Bike Comparison