trialsrfun Posted November 8, 2013 Report Share Posted November 8, 2013 (edited) REH, Robin Humphries went on to design, patent and build a prototype reciprocating engine which has no con rods, I think he calls it the Shane engine. http://www.volvoforu...hp/t-50440.html There used to be a lot of info on the web about this but it seems to have vanished for some reason? Edited November 9, 2013 by trialsrfun Quote Link to comment Share on other sites More sharing options...
pickle Posted November 13, 2013 Report Share Posted November 13, 2013 Heres a pic of dad on his Cheetah in the 1967 Dick Farqueson trial. This is the bike he had supplied by Bob Gollner and John Jackson had another which they both ran together. He did say the disc brake was useless!!! Quote Link to comment Share on other sites More sharing options...
laird387 Posted December 8, 2013 Report Share Posted December 8, 2013 Hi, I have plenty of images of Cheetahs, plus it was covered in my 'Offroad Review' in detail for which I have all the original material that went to the printers, so I could make an electronic reprint for you to be able to use on your computer, simply for reimbursement of my costs, if you are interested. I can tell you that if the frame isn't nickel plated, then it isn't original. Regards, Deryk Wylde Quote Link to comment Share on other sites More sharing options...
laird387 Posted December 19, 2013 Report Share Posted December 19, 2013 Hi, Sorry for the delay - here's the Cheetah information, all taken from the magazine that I published 'Off-Road Review'. Regards Deryk Wylde 1 Quote Link to comment Share on other sites More sharing options...
laird387 Posted December 20, 2013 Report Share Posted December 20, 2013 Hi, Another delve in the archives, another Cheetah pic, this one also from my Offroadarchive, photo by the late Gordon Francis. The Cheetah ridden by Paul Dunkley in 1967. Hope it helps. Quote Link to comment Share on other sites More sharing options...
laird387 Posted December 20, 2013 Report Share Posted December 20, 2013 Hi, and OOPS, SORRY !!! Quote Link to comment Share on other sites More sharing options...
laird387 Posted December 21, 2013 Report Share Posted December 21, 2013 Hi, Another nice 'Cheetah' shot from my Offroadarchive is this Cecil Bailey pic of Bob Gollner's model, taken in Jan 1967. Enjoy Quote Link to comment Share on other sites More sharing options...
laird387 Posted January 2, 2014 Report Share Posted January 2, 2014 Hi, Another delve into the offroadarchives revealed this 'Letter', which I published, from Peter Pilbeam, one of the team that produced the Cheetah trials machines. "I would like to make a few observations on Don Morley's article.......the first ever trials disc brake was designed by Robin Humphries and built by his father's engineering company, R E H Precision, who also built the forks and hubs designed by Robin. The disc brake was not a conventional hydraulic device but was operated by a cable moving a pair of wedges running on rollers behind the pads. The massive alloy barrel and head used on the Cheetah were also designed by Robin. I was involved with this project and I remember measuring the porting on every type of engine I could lay my hands on, then we sat at the kitchen table for hours trying to work out the best average of them for our barrel. The aim was to produce more mid-range and top-end power than the iron barrelled Villiers, which ran out of steam on a lot of the steep climbs used in those days. We bought a 'Baby Belling' electric oven for heating the barrel for fitting and removal of the sleeve, the barrel only just fitted in the Baby Belling. A machined barrel was heated in the oven, the Hepolite sleeve was dropped in and the barrel allowed to cool. The inlet and exhaust port shapes were scribed on the sleeve but the transfers, being inaccessible, were filled with copper sulphate solution and left overnight. The barrel was reheated and the sleeve was removed to be mounted on a spigot fixture on the milling machine. I then milled out the ports by eye, the copper sulphate leaving well marked areas on the sleeve. Finally the barrel was reheated, the sleeve dropped in and the port shapes finished off with Swiss files. Quite a long process and I can't remember how many we did, but I had notes on number 11 and number 14. Reference is made in the article to a larger capacity barrel. The barrels made for Cheetahs were all 250s, but a larger capacity one was made later for a 360 engine unit for a sidecar outfit - not a Cheetah - ridden successfully by Denny Brown. This used an Alpha bottom end with full flywheels and an 80mm piston. The gearbox contained BSA Victor gears in cases drawn up by Dennis Evans, cast and then machined by R E H. The case and covers were based on the BSA ones and used the Victor gearchange and kickstart components. I can't remember if the BSA clutch was used. We first tried a C15 gearbox fitted to a Villiers. We cut off the gearbox part and had it argon-arc welded, now called tig welding, to a plate which fitted the back of the Villiers engine." Yes, folks, that was the way quite a lot of the British trials machines manufacturers worked - the backs of fag packets being an overworked part of the Drawing Office stage.... Enjoy Incidentally, for those not in the know, 'Hepolite' was a well known brand of pistons, piston rings and sleeves used by many British manufacturers. They were produced in the Bradford area by specialist engineers, Hepworth and Grandage Ltd., whose factory I was lucky enough to visit on a regular basis in later years. 1 Quote Link to comment Share on other sites More sharing options...
farmer58za Posted January 6, 2014 Report Share Posted January 6, 2014 One of those 350 REH barrel/head combinations came along with my Cheetah (which is currently fitted with the 250 REH barrel) I think the cases have to be machined out to accept the bigger 350 barrel. Is that correct? Regards David Hi, Another delve into the offroadarchives revealed this 'Letter', which I published, from Peter Pilbeam, one of the team that produced the Cheetah trials machines. "I would like to make a few observations on Don Morley's article.......the first ever trials disc brake was designed by Robin Humphries and built by his father's engineering company, R E H Precision, who also built the forks and hubs designed by Robin. The disc brake was not a conventional hydraulic device but was operated by a cable moving a pair of wedges running on rollers behind the pads. The massive alloy barrel and head used on the Cheetah were also designed by Robin. I was involved with this project and I remember measuring the porting on every type of engine I could lay my hands on, then we sat at the kitchen table for hours trying to work out the best average of them for our barrel. The aim was to produce more mid-range and top-end power than the iron barrelled Villiers, which ran out of steam on a lot of the steep climbs used in those days. We bought a 'Baby Belling' electric oven for heating the barrel for fitting and removal of the sleeve, the barrel only just fitted in the Baby Belling. A machined barrel was heated in the oven, the Hepolite sleeve was dropped in and the barrel allowed to cool. The inlet and exhaust port shapes were scribed on the sleeve but the transfers, being inaccessible, were filled with copper sulphate solution and left overnight. The barrel was reheated and the sleeve was removed to be mounted on a spigot fixture on the milling machine. I then milled out the ports by eye, the copper sulphate leaving well marked areas on the sleeve. Finally the barrel was reheated, the sleeve dropped in and the port shapes finished off with Swiss files. Quite a long process and I can't remember how many we did, but I had notes on number 11 and number 14. Reference is made in the article to a larger capacity barrel. The barrels made for Cheetahs were all 250s, but a larger capacity one was made later for a 360 engine unit for a sidecar outfit - not a Cheetah - ridden successfully by Denny Brown. This used an Alpha bottom end with full flywheels and an 80mm piston. The gearbox contained BSA Victor gears in cases drawn up by Dennis Evans, cast and then machined by R E H. The case and covers were based on the BSA ones and used the Victor gearchange and kickstart components. I can't remember if the BSA clutch was used. We first tried a C15 gearbox fitted to a Villiers. We cut off the gearbox part and had it argon-arc welded, now called tig welding, to a plate which fitted the back of the Villiers engine." Yes, folks, that was the way quite a lot of the British trials machines manufacturers worked - the backs of fag packets being an overworked part of the Drawing Office stage.... Enjoy Incidentally, for those not in the know, 'Hepolite' was a well known brand of pistons, piston rings and sleeves used by many British manufacturers. They were produced in the Bradford area by specialist engineers, Hepworth and Grandage Ltd., whose factory I was lucky enough to visit on a regular basis in later years. Quote Link to comment Share on other sites More sharing options...
laird387 Posted January 6, 2014 Report Share Posted January 6, 2014 Hi David, I wish I could answer your question, but sadly my practical interest in twostrokes was very limited because I was very much involved in riding and restoring my ex-works AMC trials models and then the Ariel HT5s, culminating in restoring a very famous old bike. Naturally I did get a lot of information 'out of the woodwork' - as it were, with letters in to ORR, such as the one from Peter Pilbeam that I republished again above. Whether Peter is still around or not, I don't know, whether he sees this website I don't know either - one can only hope so - and then you might get some more information ! Cheers - and in the meantime I'll keep dredging my archives ! Quote Link to comment Share on other sites More sharing options...
dalespathfinder Posted January 20, 2014 Report Share Posted January 20, 2014 (edited) hi As there has been a lot of interest in cheetahs I will be showing one of my cheetahs at Alan wrights show at Telford It is the one with a disc brake the disc brake was made by R E H as cast in the alloy brake calliper it also has the R E H barrel fitted it has R E H forks as standard for any one who does not know they look just like cerianis are 35m but without the bottom pinch bolt and slot to clamp the wheel spindle All cheetah have the frame number in the centre of the head stock at the front all numbers start 1500 upwards two off my others cheetahs are in C D Bike issue seventeen The forth one I ride it has the cub engine been modified a little A great bike to ride regard brian Edited January 21, 2014 by dalespathfinder 1 Quote Link to comment Share on other sites More sharing options...
farmer58za Posted January 25, 2014 Report Share Posted January 25, 2014 Lovely bikes Brian. Are any of your bikes fitted with a side stand? I'd like to put one on mine and need some guidance. Regards David Quote Link to comment Share on other sites More sharing options...
laird387 Posted January 25, 2014 Report Share Posted January 25, 2014 Hi, Another Cheetah image, this time Paul Dunkley with the works 250, photographed by Alan Vines in the 1968 Kickham trial. Enjoy. Quote Link to comment Share on other sites More sharing options...
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