Torque Vs Power

Just as R.M.S, a term used in electrical power measurement is often incorrectly used, the correlation between torque and HP or Kilowatt is often misunderstood. A colleague in the motor industry mentions that at least 40% of his clients pass on information which they have ‘overheard’ when purchasing new camshafts without understanding the true role of both HP and torque in camshaft design.  The same goes for engine re-mapping. Clients are eager to see the HP but know very little about torque. Remember the huge problem MotoGP riders had when changing over from their 500cc two-stroke machines to 900cc 4-stroke machines which delivered substantially more torque at lower revs and literally ate tyres coming out of corners. Although the racing engineers know a lot more about these things than a mere layman I recall this very clearly from the first races, possibly still a major problem. The bottom line is you cannot just push HP up without it affecting your torque figures, the reciprocation is just as true.


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Pylon and Jet Engine Installations

Jet Engine - General Electric GEnx on 747-8I prototype

Jet Engine mounts – that incredible wing!

There is much said about the Germans and English (esp. Frank Whittle) with regard to the jet engine but very little in line with the airframe and designs used in conjunction with turbine propulsion. Passenger and cargo aircraft with amazing power and lift hold most of us in awe and just short of being an aviation engineer to understand the dynamics involved the layman really has very little understanding of aircraft in general. I find the aircraft wing one of the most fascinating pieces of engineering yet we all know so little about it.


Picture the last time you took a flight and recall how the wings started to bounce while taxing along the runway.

As a layman an oft asked question is how the deuce are those massive engines mounted onto the wing or tail section of an aircraft?  If you have never asked yourself this simple question then possibly you have never flown before because well, a wing is just a piece of aviation strength aluminium isn’t it?  When you take an engine, actually 4 engines like in a Boeing 747 and mount them to two wings one would think that they would break off with all that weight. Each engine weighs upwards of 4 000Kg so it is totally amazing that it doesn’t. Or is it?  Look at the bird front on before a long haul and you’ll see that the wings do look they are hanging downwards. The wingspan on a 747 is approximately 60m in length and carries nearly 200 000 liters of fuel plus four ginormous jet engines so certainly it’s going to pull downwards. If you find this fascinating just look at the Antonov An-225 Mriya, the Russian juggernaut, said to be the longest, heaviest and with the greatest wingspan of around 80m (84m).

Jet Engine - General Electric GEnx on 747-8I prototype
General Electric GEnx on 747-8I prototype
Photo Credit source: Olivier Cleynen

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Cheap Energy – Is this a Myth?

Inspired by a thread in the Science Forum on the comparisons between solar, wind and nuclear I notice there is no clear winner when it comes to implemenation. While they all have their own positives they also all have their own negatives. While we sit and ponder about our current problem  one thing becomes abundantly clear – we’re not happy with the alternatives.

Texas Pumpjack - wiki commons
Texas Pumpjack – wiki commons

Is a miracle fuel or cheap source of energy really that difficult to find?  I was intrigued by the list of articles found through Google on John Kanzius’s surprise discovery on setting hydrogen alight in a salt water solution while near a fairly high powered transmitter operating in the 15MHz band. Not so with the negative response through the “scientific” community.  Continue reading “Cheap Energy – Is this a Myth?”

Motorcycles of the 70s and 80s

I don’t think there is a hardcore motorcyclist out there that hasn’t had his favourite ride. Most tend to exaggerate performance and most will lean towards the faster bikes. Like the tales of the fishermen bikes tend to become faster and faster and meaner and meaner as the beers flow but one thing will always be apparent, motorcyclists do favour certain manufacturers and perhaps not now so much but the early stalwarts would always take the Italian, British, American and German bikes over the Japanese. The World Superbike series and MotoGP will tell you which bikes take the flag now. What about then?

Honda CB900F
Honda CB900F

One thing is prevalent, each and every manufacturer has brought out a machine which in that year was a favourite. Definitely the 900cc Kwacker for those that wanted to live dangerously, then the Suzie 1100 for the speed freak, the Yamaha RD350 to show off the 750s and the six cylinder Honda for the show off.  Most non-bikers opted for the German technology just through hearsay, I was a Ducati fan because it had such a damned incredible reputation and the older riders would boast of their British rides. Harley Davidson was for the tourists. Nowadays the only older bikes I see on the road are Honda and Suzuki – testament to their robustness. Sure Honda boasted reliability and never an oil leak. I still see the first batches of CB900F’s on the road (Cape Town). I also see them parked on the highways without a rider. I don’t care, this was a fine motorcycle – its done it’s time, going over thirty years already. On a rally recently there were a few Kawasaki ex-traffic police machines – a good buy if anything because of their previous history. In the USA the 900 and 1000cc KZ or KZ-P series were very popular – actually, still are very popular.

Growing up the closest I ever got to buying a new machine was the Honda CB900 and then the awesome Ninja 900.  Prices skyrocketed due to the drop in local currency and only if you had no overheads and a dad with a fat bank balance could you afford any of the newer bikes. Still today, nothing beats the depreciation of a bike that has been ridden by a novice or drunken rider. If I look at modern bikes in comparison to those of the 70s and 80s it’s sad to see the amount of time (and passion) spent on producing replicas of racing machines. The old bikes had straight or upswept handle bars,  the daredevils would add clubman’s or clip-ons, fairings and all the mod-cons of that era. Straight handle bars on a bike made them look like bikes. Nothing like a large twin or 1000cc with straight handle bars – not for racing but to take you from point A to pint B. Not to pretend and not to exaggerate. There is after all very few riders on the road that like to maintain a steady crusing speed of Mach I on our highways. As we get older some of the newer superbikes actually look ridiculous ridden by a rider of 50+.

I rode a Honda-6 years back. It had straight handlebars. Nothing wrong with that. I didn’t go over 140Km/Hr and neither did I intend to. I think that bike would have ridden up a vertical cliff at 140Km/Hr. If I was 25 right now I would have been too ashamed to have ridden some of those old bikes – they just lacked that Rossi look. If you crash a modern bike the results are going to be the same as those vintage machines – a wreck. Bikes wreck easily. Your bones break just as easily too. Ducati and Yamaha still make awesome looking machines that don’t have to pack a fairing and handlebars that scrape the tarmac to look mean. There some ugly looking street racers out there. I’ll be honest and say upfront that I want an old bike. I want a bike that is reliable, can get the ton (mph) easily and be light on juice. Triumph springs to mind. The RD350 was beautiful. The Kwacker Z900 was orgasmic. All Ducatis are heartbreakers. The list goes on and on. Older bikes had a tendency to tank slap. Modern bikes don’t. Older bikes could also be ridden by real men and not crash.

If we reflect back on the older bikes there is one thing that we can be certain of – most bikers of the time had to be able to conduct their own running repairs, many of them had some very dodgy design quircks, they may have been quick off the mark even in today’s terms (2-stroke) but their handling could be dangerous. Let me rephrase that, their handling WAS dangerous to a novice rider and even some experienced riders.  For some obscure reason old motorcycles are sold for absurd prices, even those not running.  I’d love to pay 3000$ for a Honda 6 but I won’t unless it’s in mint condition. Many of them aren’t.  Coming from South Africa a vintage Harley sounds like a good bet but the prices are unbelieveable. Where are the bike scrapyards?

The 1980s metric – the Jap import. I stick to my 1970s and 1980s rule – buy an old bike.

  • Suzuki had some very suspect electrical wiring especially in the charging circuit. When buying an old Suzie make sure you have enough cash to do the upgrade, if you’re an electrical type guy you’ll quickly pick up the pitfall in the charger, especially when you lose ground.
  • Honda manuals aways boggled my mind with the special tools to use.
  • Kawasaki and Yamaha – well, possibly a favourite of many. I’m a fan of all Jap bikes so won’t be biased except to say do the read beforehand. All bikes have their quircks. To me Kawaski would be first choice, especially if you can get your hands on an old police bike. A friend mentions workshop bikes as well.  The engines have normally been looked after or at least you should not have smoke or lack of compression. Police auctions are a good hunting ground.
  • Try to veer away from anything that has a microprocessor – the engine control unit is not something you can discard.  Stay away from engines with cooling fins broken off (don’t ask me). If the engine idles without the tacho jumping all over the place is a good place to start. Older bikes rarely have a service record.
  • BMWs and Harleys can easily clock up high mileage. It means nothing unless it smokes like Uncle Billy Bob.
  • I love big twins. Yamaha and Kawasaki both made twin 750cc bikes.  I don’t love bikes producing HP at over 10 000 RPM, especially if you need to do maintenance.  Honda Hawks are usually very nice buys.
  • Please comment and give me your favourite scrapyard. In South Africa the main bike dealerships that may not be prone to ripping one off are usually up north in the Gauteng region. (Johannesburg).
  • Always have a motorcycling buddy that is an engine fanatic – they pick up chassis problems as well.
  • Most 80s metric bikes have lots of gizmos which can be fitted without having to make major changes.
  • A rusted frame is a no-no unless you have a spare.
  • Know what you are looking for before parting with your money.
  • There are lots of very informative websites out there – read them and take heed.

Please add your comments and let us know of your favourite scrapyard or supplier. Motorcycles are becoming more and more popular – Chinese imports are hugely popular but building your own bike is good for the soul. They also have more power 🙂