2013 Honda NSS300 Forza

[terryvanman]

To give you some idea of how low, the Forza is listed as 716mm and its little cousin the PCX has a seat height of 761mm
So in real money that works out at two inches lower than a PCX.

Looking good for moi

[MrGrumpy]

Grumpy, I don't think you are a simpleton. It's all relatively new stuff though so not many people out of the engine engineering world have heard of it. Here it is...rough diagram which gives a clue to how it works.

So how come an apparently so simple change hasn't been thought of before?

[gn2]

Not a new idea at all, it has been used for decades.

[Data]

Yes, gn is right. But don't confuse 'offset cylinder design' with many descriptions given on the internet showing motorcycle engines with their cylinders leaning forwards or backwards. Thats' not offset cylinder design as we are talking about here. A more correct title is 'offset crankshaft' design. It's not new but has been little used for many reasons. It's main use has been in specialist engines. It is new in the current crop of engines for bikes, and soon cars, and when aligned with all the new tech stuff (the new direct petrol injection into the cylinder instead of into a Plenum Chamber) and other new materials, is an unbeatable design. It is going to be used increasingly in many engine designs from what I hear. It is particularly good when combined with modern Variable Vane Turbochargers with Variable Nozzle Technology on petrol engines. As many of you will know, petrol engines are taking over from modern diesel engines due to emission control issues. VAG, currently selling 78% of their cars as diesels, will undergo a dramatic reversal of their sales to 70% petrol engined cars in the next 2-3 years leaving diesel cars in the shadows. To do this, many petrol engines are/have being redesigned, some engines from all manufacturers will have offset engine cylinder crank designs to make them perform even more like diesels and give very good miles per gallon. Typically, a 1.4 petrol engine is easily capable of 140ps with 250nm of torque at 1400rpm and 67mpg, 0-62 in 8.5 seconds, in a medium size car. Vibration is not really an issue as mentioned in earlier articles. These cars and engines exist now in the VAG group but not many with offset cylinders yet to my knowledge. It's a very exciting time.

[poldark]

Interesting info and insight Data, I'm intrigued by the suggested reversal of current Diesel/Petrol share. For me a critical factor is the pan-European (except the bl**dy UK!) advantageous pricing of Diesel at the pumps.

Even if Petrol engines achieve similar mileage to Diesel, it doesn't take long to recoup the higher initial outlay for a Diesel car if the fuel you buy is always 15% cheaper at the pump, as long as your mileage is reasonable.

[Data]

Yeah...it's very frustrating paying much more for diesel fuel than they do on the continent. I've always been a diesel advocate. But now there is a very good reason to buy petrol. VAG has the new range of Turbocharged Stratified Injection engines which has revolutionised the petrol engine. Their 1.2 litre 105ps engine (not a new unit now, been out for about 3 or more years) is amazing with 175nm of torque at 1500rpm. It isn't offset crank but it will no doubt be going that way soon. I've driven it and it goes just like a diesel with amazing pick up in any gear. It's cheaper to buy than it's diesel counterpart too and delivers massive mpg's. It easily gives better than 1600cc to 2000cc petrol engine performance. All this sort of tech is finding it's way down to bikes and scoots but minus the turbocharger which isn't really needed on bikes anyway.

[StephenC]

With all this tech talk going on (very interesting, pls carry on): can someone tell me why we have to put up with engines which don't develop peak torque and hp until stupidly high up the rev range? Surely peak torque at around 2500rpm (as opposed to 5000rpm) would suit CVT much better, giving us improved mpg and longer life expectancy?

[gn2]

Best bet is remove or cover the rev counter then you won't know or care what the rpm is.

[StephenC]

Best bet is remove or cover the rev counter then you won't know or care what the rpm is.

Can I do the same with the speedo, officer?

[gn2]

So long as you've got ABS I don't see why not