I thought I'd post some more info on this bike, what little I have anyway (!), following the interest generated on a previous thread related to the 'MX Bikes' website (www.mxbikes.com) and my discovering a pic on there of one of these rarest of Greeves hybrid 'specials'. I hope it will be of interest to newer members who may not be familiar with this fascinating machine.
Information on the Cheney Greeves project was published in 'Leading Link' #21 (August 1988), and was based around an article on the prototype from 'Motor Cycle' (22 December 1966 issue) by Peter Fraser, who also tested the machine for the peice.
It was conceived by Eric Cheney at a time of change, when the big 500cc four strokes of the day were being challenged (sorry!) in the class by the lightweight 360cc two stroke machines, with an eye to achieving similar results in the 250cc class. Peter Fraser was very impressed with the bike when he rode it, as were other high profile riders of the day.
Finished in a combination of Jaguar grey paint and polished alloy, the bike was a typical example of Eric Cheney's superb craftsmanship. The brazed frame was fabricated from Reynolds 531 tubing and fitted with Timken taper-roller steering head bearings, with fully floating (and shrouded) needle roller bearings at the swinging arm pivot. To facilitate chain adjustment, the rear wheel spindle was located in oblong serrated plates which engaged with matching serrations on the swinging arm. Forks were Ceriani and mounted in Cheney fabricated yokes. The weight of the bare frame and swinging arm was only 17 1/2" lbs (!), and the wheelbase was 54". The weight of the whole bike was only 198 lbs, and a further 8 lbs. could be saved with the fitting of Cheney lightweight wheel hubs. This figure was some 20 lbs. lighter than an 'average' two fifty of the day!
Another innovative feature was the location of the light alloy 1 1/2 gallon fuel tank underneath the seat, aimed at lowering the centre of gravity, with the 'fuel tank' merely being a 'shroud' to protect the rider's knees from the up-and-over exhaust system.
The engine was a 246cc Greeves Challenger, with the exhaust port modified and relocated to a central position and the light alloy expansion chamber retained by tension springs. The carb was a 1 1/4" Amal Concentric and the standard Stefa ignition was retained. The gearbox, a modified BSA Victor unit, was attached to the rear of the crankcase by small plates. The Victor clutch (with duplex primary drive) was fitted in a slightly lengthened Greeves chaincase. Eric Cheney favoured this gearbox for it's robust tooth and shaft dimensions, and positive gear selection.
Pics 1-4 below are from that 'Motor Cycle' article, and the final pic is another image I managed to find on the net. There is very little out there about this bike! Note (on Pic 4) the chain guide attached to the brake torque arm, dished bolt heads, and attention to weight saving and detail everywhere!
More to follow....
Brian.
Information on the Cheney Greeves project was published in 'Leading Link' #21 (August 1988), and was based around an article on the prototype from 'Motor Cycle' (22 December 1966 issue) by Peter Fraser, who also tested the machine for the peice.
It was conceived by Eric Cheney at a time of change, when the big 500cc four strokes of the day were being challenged (sorry!) in the class by the lightweight 360cc two stroke machines, with an eye to achieving similar results in the 250cc class. Peter Fraser was very impressed with the bike when he rode it, as were other high profile riders of the day.
Finished in a combination of Jaguar grey paint and polished alloy, the bike was a typical example of Eric Cheney's superb craftsmanship. The brazed frame was fabricated from Reynolds 531 tubing and fitted with Timken taper-roller steering head bearings, with fully floating (and shrouded) needle roller bearings at the swinging arm pivot. To facilitate chain adjustment, the rear wheel spindle was located in oblong serrated plates which engaged with matching serrations on the swinging arm. Forks were Ceriani and mounted in Cheney fabricated yokes. The weight of the bare frame and swinging arm was only 17 1/2" lbs (!), and the wheelbase was 54". The weight of the whole bike was only 198 lbs, and a further 8 lbs. could be saved with the fitting of Cheney lightweight wheel hubs. This figure was some 20 lbs. lighter than an 'average' two fifty of the day!
Another innovative feature was the location of the light alloy 1 1/2 gallon fuel tank underneath the seat, aimed at lowering the centre of gravity, with the 'fuel tank' merely being a 'shroud' to protect the rider's knees from the up-and-over exhaust system.
The engine was a 246cc Greeves Challenger, with the exhaust port modified and relocated to a central position and the light alloy expansion chamber retained by tension springs. The carb was a 1 1/4" Amal Concentric and the standard Stefa ignition was retained. The gearbox, a modified BSA Victor unit, was attached to the rear of the crankcase by small plates. The Victor clutch (with duplex primary drive) was fitted in a slightly lengthened Greeves chaincase. Eric Cheney favoured this gearbox for it's robust tooth and shaft dimensions, and positive gear selection.
Pics 1-4 below are from that 'Motor Cycle' article, and the final pic is another image I managed to find on the net. There is very little out there about this bike! Note (on Pic 4) the chain guide attached to the brake torque arm, dished bolt heads, and attention to weight saving and detail everywhere!
More to follow....
Brian.
Attached Files
Comment