Norton Reinvented Rotary Engine

piston engines have been developed for over a century but many believed a rotary was here to change history we all know how they turn out but besides mazda and sax there was one more company that also put more hope and time into the wankel engine development [Music] the story of norton's rotary engine is full of passionate people important decisions on the edge of bankruptcy and one inherited engine license which brought the resurrection of a then dying motorcycle industry in britain in 1972 bsa as birmingham small arms company was struggling and was merged with other brands under a norton village triumph joint venture the new firm received solar motorcycle projects from bsa one of which was a rotary engine bsa had been working on it ever since 1969. ninety percent of the projects from bsa were cancelled but not the rotary thanks to a guy named david garside being a mechanical engineer who previously worked at rolls-royce developing a diesel alternative of felix wankel's patent he managed to persuade nvidia's boss dennis poor to let the rotary live and do their best with it garsite wrote down the whole development into a single document his inspiration came from the hercules w2000 which held a fictional and sucks single rotor in its frame he did basically the same thing put a 294 cc km 914 engine into a bsa b25 starfire motorcycle a 30 horsepower power plant was found to be insufficient but it was smooth and allegedly reliable garside doubled the number of rotors and now the real r d began fundamentally the km-914 engine was air-cooled and so was the reworked norton's one it actually shared many parts from the german unit besides regular thickness on the exterior the engine would cool itself from the inside by sucking filtered air mixed with fuel and oil and sending it through its internal paths like an eccentric shaft and the rotors it worked but was far from perfect the winkle itself runs really hard and can be underpowered under certain circumstances garside looked deeper into the problem and found out that the sax engine would only work consistently with a fan water cooling was proposed but allegedly would not be well received by customers they stuck with the charge cooling but did some interesting trickery first the carburetors were moved further away from the filter between a plenum and combustion chambers then half lemon openings in the housings from the original bsa concept were enlarged into full lemon-like holes now without a pressure disruption this cooled down the engine more efficiently but heated up charged air which is not ideal for volumetric efficiency initially proposed to be cooled by water to air intercooler garside introduced a large press steel plenum of a volume of 5 liters which lowered the air temperature by 20 degrees of celsius this intake piece was a part of the motorcycle frame and after the plenum air was drawn into the constant velocity carburetors and then the rotor chambers some serious work was placed into redesigning rotors as well the stock came 914 and later kc-24 rotors worked fine but it was found out that by reshaping a rotary size 5 to 10 percent more torque could be gained however it shortened the lifespan of the rotors from 60 000 miles to about 5 000 miles at most with cracks occurring after just 2 hours on a test bed at 7 500 rpm the internal design of the road was changed with added cooling things and thereafter their rotors easily survived over 75 hours of wide open throttle at 7 500 rpm to gain the most of the top main power the most aggressive type of porting was introduced to the engine peripheral ports giving the engine the typical and famous proprop sound it made idle quad rough but engineers were able to achieve a stable misfire free idle speed of 850 rpm overall the engine had over 85 percent high horsepower output than the original sucks engine just thanks to the improved cooling and chasing higher volumetric efficiency while the hercules produced about 91 horsepower per liter the norton classic had over 134 horsepower per liter it had a much higher rev range a higher compression ratio of 9.21 and pretty good fuel economy too an oil pump similar to a 2-stroke engine one was used to inject lubricant to essential parts of the engine and in the end a bear engine weighed only 22 kilograms garside stated that the fuel consumption of the twin rotor was competitive to the best-class 4-stroke engines and much superior to any 6-cylinder which they considered as competition after a laborious development it is interesting to know that the initial target was an output of 50 to 60 horsepower with any given amount of rotors needed the aim was more towards performance classes as they thought it would be much more expensive to compete in the low power four stroke singles and two stroke twos on the categories the first mentions of the upcoming rotary engine reached press media yet in 1974. however the very first usable rotary norton rolled down the factory line in 1984 over a decade later after the first approval in 1972 it was called the interpol 2 and was only sold in fleets for civilian and the military police and rac in britain it used an 85 horsepower engine run very smooth and provided a usable pull yet from 1500 rpm [Music] built side by side with the interpol 2 in 1987 a northern classic appeared in a limited run for public sale as reliability had been already tested in the fleet model line 100 customers could buy the new rotary powered classic today the model is highly collectible but it was not the last wenkel norton for ordinary people [Music] in 1988 a northern commander was introduced as a successor to the interpol 2. it was fully fared and sold in two versions a police single-seater and a two-seater for people like you and me the difference was that the engine was re-engineered and accommodated a water cooling of the hot part of the rotor housings the liquid-cooled engine also received an intercooler besides the intake plenum for more superior charge air cooling during hard accelerations a part of the air bypass the engine internals and was drawn directly into the carburetors using the richer mixture as an internal cooling compensation sales were struggling and there was a patient employee brian crackton who spent countless hours squeezing more power out of the twin rotor he managed to achieve 96 horsepower about 12 increase it was evident that a racing bike could be competitive and although crackton would not receive support from above he was allowed to work on the engine in his spare time recycling old and crash interpol tools the 588 cc unit eventually reached 125 horsepower on a test bench by improving and separating carburation and cooling while retaining the stock compression ratio it used 34 millimeter twin my cooling cups for fuel delivery a constant bike was able to go beyond 155 miles per hour allegedly up to 170 miles per hour and was dubbed the rc-5888 the factory's ignorance would disappear with a company owner changeover in 1988 and a year later the bike received john plays special sponsorship the bike was achieving records and victories all over the country including the isle of man tt and british f1 allegedly the highest output of the rcw-508 ever achieved was over 140 horsepower as its legacy naughton introduced a detuned road going replica the f1 using the motor from the commander however the racing success did not help sales and the f1 was the last norton rotary motorcycle offered [Music] more gregton could not stop working on the rotary engine he partnered with rotron power a rotary aero engine expert and kept developing the unit first a cracked crackton cr700p was created with a 200 horsepower 700cc engine using an interesting but not specified sealed pressurized gas cooling system with a belt-driven pump in 2021 crackton's culmination of his engineering career was announced the subject was called a crackton cr700w and it was a twin road superbike following his experience in norton it was created thanks to a 12 year old cooperation with the rotron company the engine is built from an in-house machined aluminum alloy with engine wear surfaces covered in a molybdenum and a nicosil for the lowest possible friction and high wear resistance the eccentric shaft is made of a steel and the rotor ceiling is secured thanks to two-piece silicone nitrate ceramic apex seals there is also a titanium and inconel exhaust ejector system creating a vacuum for the maximum possible internal rotor the engine is said to have close to zero wear and should hold a season full of track days you

Channel: VisioRacer

Views: 152,099

Keywords: VisioRacer, engine, sound, Norton, rotary, Wankel, Triumph, BSA, F1

Id: g7INxIkReNM

Length: 12min 14sec (734 seconds)

Published: Sat Apr 16 2022