New V-Twin engines from Honda

Honda will introduce the next generation of its V-Twin series of horizontal and vertical shaft engines worldwide in the second half of 2009. The six models of the range offer approximately 10% more power, approximately 10% lower fuel consumption, lower exhaust emissions and lower noise than their predecessors, said the company.

The 15.1 kW GX/GXV630 will replace the GX/GXV610, the 15.7 kW GX/GXV660 will replace the GX/GXV620, and the 16.6 kW GX/GXV690 will replace the GX/GXV670. The new engines are designed for construction, generator, and lawn and garden equipment, and Honda told IRN it will "gradually" remove the older engines from production.

Contributing to the improved performance of the engines are: hemispherical combustion chambers, radial valves, an increase in compression ratio from 8.3 to 9.3, variable ignition timing (digital-CDI), and an integrated cylinder and head structure. These features improve combustion and provide better cooling, said Honda, while allowing the engines, all of which weigh about 45 kg, to exceed "the world's most stringent emissions regulations without the use of a catalyst."

Other features include a new cooling fan (for higher air flow and less noise), aluminium pushrods positioned in external tubes (for better cooling of the cylinder), a resin type cam shaft (low noise), and a full-pressure lubrication system. The engines have a twin barrel, inner-vent carburettor and a new multi-layer, paper element fuel filter, with reduced replacement frequency.

An option on some models will be a control box incorporating all engine controls: built-in throttle lever, choke lever, and Honda's new Oil Alert (low pressure) warning system. The box will also house a digital hour metre.