The engine that we're looking at here, at 1084cc, may not be the biggest capacity on the market, but is nonetheless quite sizable for a parallel twin, especially given the current glut of twins that are in the region of 700-900cc. The Honda big parallel twin's configuration is - like the 750cc powerplant in the new Hornet and Transalp the Unicam, in which just one cam is used to operate both the inlet and the exhaust valves, with two of each per cylinder. Initially, this seems like something of a retrograde step when you remember that motorcycle development with Honda went from the SOHC 750 four launched at the very end of the Sixties to a DOHC inline-four a decade later, which was much the same with just about any engine development programme that you can think of. The process of poppet valve to sidevalve, to overhead valve, to overhead single cam and then overhead double cam looks to be irreversible, but Honda has contradicted that to a certain extent with the new 750 and 1100 twins. Of course, the change isn't simply a reversal of technology, as there is a technological reason behind the return to a single cam that actuates both inlet and exhaust valves. A single cam not only weighs less than two (clearly), but also it takes up less room, and the space that has been saved can be used for an expanded airbox feeding downdraught throttle bodies; for a change in frame design; or for a reshaped fuel tank. Or all three. And, partly thanks to the friction-reducing roller followers on the operating arms (leading to screw and locknut adjusters atop the valves) there is no potential loss in engine performance. The only issue that might arise would be when tuning the powerplant and an alternation in valve timing was required, as an adjustable cam sprocket would change both exhaust and inlet timing together when for the required tuning they may need to be changed independently.
Bu hikaye Motorcycle Sport & Leisure dergisinin August 2023 sayısından alınmıştır.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 9,000+ magazines and newspapers.
Already a subscriber ? Giriş Yap
Bu hikaye Motorcycle Sport & Leisure dergisinin August 2023 sayısından alınmıştır.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 9,000+ magazines and newspapers.
Already a subscriber? Giriş Yap
Honda CRF1100L ES Africa Twin
Without panniers he was adventuring nowhere - so at least Bertie's got something sorted now
BMW R 12 nineT
Chad gets a track day surprise when BMW's R 12 nineT turns out to be surprisingly fun on track
Test fleet: VOGE 525 DSX
After testing the Voge's abilities on a long ride, it was time to take it to the Cotswolds and see how it would manage on the rougher stuff
Portuguese Perambulations
Nearly over before it had begun, a brief workshop stint allows Spain and Portugal to be explored
Highway to Heaven
Three friends take on the challenge of riding the length of Canada, from Vancouver in the southwest to Inuvik in the north. The road is long, the conditions merciless, and wildfires are tearing through the country. To top it all off, the final leg of the journey is the ultimate test of gravel riding skills, nerves, and courage - it's the legendary Dempster Highway...
Battlaxes at the ready!
We tend to take tyres for granted, never really looking at them in any detail, or at how they work, just hoping that they keep us shiny side up at all times. Even in the wet
Ducati Riding Experience
When I rode the Ducati DesertX to France last year, I did have a bit of an explore on some easy fire roads and gentle green lanes in the wilds of the Médoc area, but was left with the feeling that, had I the experience, the DesertX would have been capable of taking me along some more extreme trails to some even more exciting places. If only there was a way of finding out just how well the Italian adventure bike could cope with some more extreme terrain...
Four pot flyer
Many said that sports bikes, and particularly bikes in the traditional Supersports class that was populated by 600cc inline fours, were dead. Maybe they spoke too soon?...
Eastern adventurer
With an increasing interest in smaller capacity adventure bikes, the market expands with a new entry
First Time Lucky?
It's ironic that the first all-new MV Agusta model to hit the marketplace right after Italy's No.1 trophy brand was acquired by Austrian giant Pierer Mobility, owner of off-road titans KTM, should be the company's first dual-purpose model of the modern era, powered by MV's all-new 931cc three-cylinder engine that's destined to form the basis of a whole series of new models in coming months and years.
