Best Motorcycle Engines ever Built


As an add on to the article which was more rage than prose, the Nissan QR25 series motors with their set of complicated problems, it would be pertinent to cover motorcycle engines which made history, some famous, some infamous. Motorcycle engines are not supposed to outlast motor car engines, they are high revving, power comes in at the top end with most of the Japanese machines and to a larger degree motorcycles just get thrashed. There are some engines that just lasted forever or were the best engines to nitro, turbo or just plain race tune. The 500cc triples by Kawasaki is a case in point, phenomenally fast, the widowmaker 750cc MachIV H2 designed for robot to robot straightline dragging and the the ever popular RD350cc were the rage in my day. Two strokes are simple beasts to work on, light and simple. They weren’t as reliable as four strokes but if you were the fastest kid on the block who really gave a damn. The Kawasaki bikes were notoriously poor handlers and cornering was never part of the equation.

Ducati 851

The website Visor Down has a very good article on the top ten motorcycle engines ever developed. There are complaints about not seeing certain engines, the BMW boxer Twins being just one of them but I think from a popularity point of view they are spot on. The fact that they added the NSR500 is a case in point. I don’t know of anyone driving these animals today but one thing has to be said – nothing could beat them.  Looking back I’d say if anyone has not ridden a two-stroke hasn’t ridden a bike, full-stop. I drove many small capacity two strokes in my younger years and the only big one was the 750cc “waterbus” from Suzuki and boy could this bike accelerate. Sadly, I never rode the RD350 although it was rumoured to be the best out there when it came onto the tracks and street racing. It was rumoured to chew big 4s for breakfast – it wasn’t cheap but still a lot cheaper than the 750s of the day. The RD350 used torque induction – I rode an RD125cc and it definitely outperformed any other bike of it’s class.  Getting onto Honda twins, every heard of the Honda 450cc – an interesting aspect to the 450cc was the use of torsion bars to close the overhead valves instead of springs. This allowed the Honda to run over 6000 RPM, something which ‘bigger’ twins could just not do in the 60s.  This made it a very interesting bike to race with, especially against bigger British twins. As kids, we had one in the house. It had done it’s time (rather aged compared to the bikes of the era – late 70s/early 80s) but the engine was still rock solid, didn’t leak, didn’t smoke and pulled like crazy. I don’t know what happened to it.  My first big bike was the Z750 Kwacker, a very nice twin. Easy to work on but heavy as a Mac truck. At the time it was possibly the slowest 750cc out there but then again it wasn’t designed for performance, Kawasaki had enough of those floating around.

If I had to put money on the best bikes around in the 70s and early 80s it could only have been the Honda 750 fours, the Kawasaki 900cc, the Katana and the oft mentioned RD350. All based on the awesomeness of the engine, nothing compared to now but that which could be fixed at home. Putting money on the MOST awesome machine between mid 70s until early 80s could only have been the six cylinder Honda CBX 1000cc. There were no worst bikes although enthusiasts are bound to disagree.  The best looking bike was the Katana. My favourite manufacturer has always been Ducati – Visor Down is spot on when they slot the 851 in at #1. They are also spot on to list the Kawasaki 500cc H1. I never rode one, I never wanted to ride one – just too many bad rumours. Read about a new ride here on the H1.

If I was going to buy a bike now from the classics of yesteryear it would be a CBX or the Suzuki GS1100, preferably a very good nick CBX. Second hand prices are ridiculous of course so if you need to get one make sure it’s never fallen and has a full service history. If you don’t know bikes, this one is going to cost you an arm and a leg to fix.

I saw a workshop bike, 851 ten years back going for U$7 000. If only I had the money. I wouldn’t have driven it – it would be in the lounge instead of my plasma screen.

Nissan QR25 Cam Chains

Now here is something to put into your pipe and smoke. Yes, cam-chains do stretch and they do cause mayhem on your ECU, sometimes so bad that your car won’t start and it will leave you stranded. I have a Nissan which has the QR25DE motor and this is what happened. The car would start surging after hard acceleration, pull over, switch off ignition, re-start and the car would behave just fine.


Once the ECU (Engine Control Unit) warning light came on. Then the car remained in limp-mode. Switching off and restarting the engine ran just fine. Now why on earth would the control unit allow the engine to run if there was something wrong with the valve timing. Unfortunately, being a performance engine, this sis a safetyguard. A car that has been religiously serviced from day one, a car that I was told had an incredible engine, a car that the service center told me had a cam chain and not belt and which only needed replacing when it started becoming noisy. Now here’s the thing, the problem was caused by a stretched chain which did not make a noise. I will play the victim here because I am not working on the engine and can say anything and my raging is not at Nissan, it’s at modern design. The bill is going to amount to R20 000.00 or U$ 2 100.00 – I believe the engine has to be removed and three chains have to be replaced. I don’t have the workshop manual – forums suggest two chains – one for the valve timing and the other for balancer shafts. On previous services nobody picked up a noise, the last service was 5000 km back. Strange or Just Plain Bullshit?

Personally speaking I am just tired of all the crap that goes with modern cars – we must buy a new car with extended warranty because if something goes wrong we need to pay the mechanic (technician? engineer?) the same rates as a medical doctor.  We are been held to ransom by the car manufacturer. I do not want a car with all the fancy gadgets that go with it to make it run like clockwork and have exhaust gas emissions of an electric motor. I smell bullshit in the air.  If the engine had a stretched camchain there should be a readable error code for all to see, just like a standard PCs error log. Then we know what is wrong before taking it to the dealer. Not some innuendo which can only be read from a very specific analyser. Yes, I am venting but I think engines have not evolved that much, the electronics hasn’t evolved that much but design has become poor and I base this more on layout, not the electronics.  Why does one have to take the engine out to replace a cam chain?  Or the starter motor? Let’s start seeing some clever designwork where all parts of the engine are accessible.  I’m not looking at the racing enthusiast – I’m looking at the old V6 motors of yesteryear (read Ford V6) – fit the necessary fuel injection and sensors in but let’s have some transparency – an engine fault that tells the user what the problem is.  Start using sensors that are colour coded that are clearly defined in the user manual and that next time you buy a car you know what the sensors are and what they do. Long time back the DIYer could do a full service in his backyard. Nowadays the engine checklight goes on and that’s it. $$$$$$$$.

Easy to work on cars, early Escorts, Subaru, early VW, Beetles.  Want some links:

I would have liked more pages with Japanese or British flavour but who cares, older cars were easier to work on. Never as easy as electric though!