Barry Sheene 1976 XR14 RG500 Restoration - Part One 

I had a motorcycle police rider stop me and say the same thing he had been following me thro thr back roads in tarlorly chesere for a couple of miles as i razzed my kh250 thro the lanes, he told me off also for wearing a non road leagal Simpson full face helmet, the first star wars style, he pointed out it was for competition use only,

I still wheel out my 87 TZR 125 and wring its neck every so often, when this came out it meant that at 17 years old you could get on a 125cc with 26hp (un-restricted). I'm nearly 50 and its still a blast to ride.

How very true, a damn shame Barry's left us.

It far from being JUST a bike .It's the bike that brought so much happiness to Barry his family team Suzuki and the thousands of Brits that followed him and even a few that didn't.

It reduces the unsprung weight so the wheel and swingarm assembly react at little more easily to bumps. It's the same thing with reverse-mounted forks on later bikes. The less unsprung weight, the less the suspension has to work - wheels, brakes, sprockets, hubs and fork sliders etc. are all unsprung. If you get your bike and lift the rear off the ground, disconnect the shock/s and try to lift the rear wheel by hand you'll understand the concept more readily.

@@pwollerman thank you for the great explanation. I had never seen shocks mounted like this.

brittenv1000 thank you. Much the same reason we used to fit alloy rims, and why cars used “Mags” - lightweight magnesium wheels, although mostly cast aluminum in practice. The more reactive and supple suspension, the better to get increased power to the ground, better steering response and better brakes. All those rely on the rubber being in contact with the road.

This might give more insight into "unsprung weight" as well as the other dynamics related to the rotational mass of wheels: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-PGGiuaQwcd8.html

I will never like 4 stroke racing motorcycles, motorcross/supercross included. Those were talented riders to handle the vicious powerband with minimal electronics on a carburatored 2 stroke

@Warren552011 what can I say ? Sir Barry Sheene was the "six million dollar man " before the Tv series with Lee Majors , the real Highlander many years before Christopher Lambert, the only one Iron Man before Robert Downey Jr. He was a real super hero, in his life, on racing and, unfortunately,in his death.

Along with hi-viz jacket and trousers, hard hat, goggles and welding gloves, no doubt.

It must have once used an oil injection system instead or possibly in conjunction with premixed fuel. Seems at first unthinkable that a serious race bike might use an injection system,but there are performance advantages possible with an injection system. The amount of oil injected can be set for a different ratio at various rpm's. Not possible with premix. The weight penalty is minor with just the tank,hoses ,pump,and bolts adding mass. The oil does not factor in as it would be in the tank anyway,correct?

Oil pumps were often run off of the mechanicals of the engine,and are not always electric. An example would be the late 60s-early 70s Yamaha AT-1 and DT-1 motorcycles that were so popular. The oil pump is located under a small outer cover on the engines side case. I'm not positive, but I believe mechanically operated oil pumps were most commonly used. And here I am just asking out loud, as I do not know; would a race bike that I assume has no battery, run an electric item off the magneto, complicating the ignition system at the risk of a DNF? I have one example somewhat similar that I know to be true as I saw it. Former World Motocross Champion Georges Jobe (RIP) found himself without sponsor in the FIM 500cc series one year, and being a strong minded individual as well as quite inventive, decided he would rather NOT ride a Honda (Honda had been a former employer of Jobe) as it actually would be even better for Honda if Jobe won a Title or races on a stock Honda than if he won on a factory (HRC) supported Honda. They could claim a stock Honda was better than the competitions works racers,and it would be true! And for free too! So Jobe built what he felt was the best he could build without it being a Honda. Well,sort of not. He built a Yamaha 490, normally an air cooled machine, by using an HRC Honda cylinder he no doubt had left over from his Honda days. It was of course a water cooled cylinder he was grafting onto an engine never meant to pump water. So no mechanical means to power a water pump existed on the Yamaha engine. Now the relevant to our discussion bit. Jobe, to cool his Honda/Yamaha, used a electric water pump taken from an automobile,but instead of using a magneto equipped with a "lighting coil" so called because it is usually used to power headlights on a machine that lacked a battery to do so, he used a small battery that needed recharging between each moto instead of complicating his ignition system and risking a moto ending loss of ignition to his engine. If the battery died or other failure happened he might still complete the 45 minute moto even if his bike overheated. I believe such concerns would have Sheene avoid an electric powered oil pump. Mechanical reliability is paramount to winning championships in all forms of motorsports. I have NEVER heard of a gear driven oil pump failure of any motorcycle. I have on an automobile though.

@@bobbyphillips2538 I was assuming it was to inject oil to the fuel. Mosy 2 strokes don't have pressure fed lubrication or any oil in the crank case. I looked on line but the info sounds dodgy. It says premixed fuel/oil is fed to the main bearings.

Because of the two strokes method of fuel induction, the crankshaft bearings would receive no lubrication were it not for the oil mixed with the fuel. I always described the method a two stroke vs. a four stroke intakes fuel this way; A two stroke uses both the top and the bottom of the piston at the same time whereas the four stroke only uses the top , above the piston to do all the required tasks. So the two stroke gets it done in half the time. Since the thumper never has the fuel charge underneath the piston its crankshaft can wallow in an oil bath. Not so with a two stroke. Intake of fuel,done on the four stroke when the intake valve is open and the piston moves down, is done on the two stroke as the piston moves up creating a vacume under it and drawing fuel in underneath it to be forced up when it comes down. More later must go

Vasilli Panin, on a race bike such as Sheene's, where would you draw power for an electric oil pump. The magneto is not capable of this, as for example a motocross bike cannot power a headlight. To provide power for any accessory, be it light or pump, requires another coil inside the magneto, like a Kawasaki KDX off road model has, that a KX lacks. Sheene has no battery on his bike as he has no electric start, again like a motocross bike as there is no need for one and its useless weight.