The CCM Roadster with 65% more power

Mick Keogh has managed to squeeze an extra 65 per cent more bhp from a CCM Roadster, giving it 78bhp. Makes you wonder what he’d do with a Hayabusa…

Devon-based Mick, of tuning firm Sportax, is still not satisfied.

He said: ” It’s a personal quest. The motor is fantastic compared to stock now, but it’s still a little flat. It could do with a bit more top end. ”

Keogh has been this way before. He took a 30bhp MT500 Armstrong and turned it into a 75bhp beast. It remained user-friendly and reliable, too.

Keogh also builds single cylinder engines for road racers, sprint enthusiasts and hill-climbers.

The CCM’s 78bhp is harnessed in a featherweight 138kg (303lb) chassis. That gives it a power-to-weight ratio of 0.57bhp/litre – similar to a sports 600.

Keogh had to modify or swop most of the main engine components. The barrel had to be bored out to give the engine a 648cc capacity. A 102mm piston fills the gap and the head has been reworked and given larger valves.

The 36mm inlet valves are now 40mm stainless steel and the 30mm exhaust valves are now 2mm bigger. Keogh’s experiments to find power with reliability saw the sacrifice of four heads in an effort to find a way of fitting the valves without them overlapping and hitting each other at high revs.

The compression ratio is now 11:1, up from 9.2:1, and the bike thumps out 58ft.lb of torque, up 24ft.lb on stock.

The clutch has had to be redesigned ato stop it slipping at anything over half-throttle.

With more than a week’s worth of tuning work involved, together with some very expensive parts and closely-guarded know-how, getting a similar spec motor from Sportax will set you back around £5000.

Sportax is also working on a range of chassis goodies for the bike. Details: 01822-841063.