Q. I have been riding for 47 years and am heading for retirement, so I want a bike that’s easy to push around, that I can ride all day and is cheap to run.
I like the Honda 125 Varadero, but can it be derestricted as I do enjoy a bit of acceleration?
Davidmdixon, MCN forums
A. Anything is possible, but you would have to throw quite a lot of money at the project. The major restriction is the exhaust headers.
The front pipe is 11mm bigger than the rear, so the back pressure from the rear cylinder slows down the front pot because of the effort to push gases through a smaller diameter pipe.
Blow through a Calypso drink straw then through a normal one, same principle.
Increasing pipe size is tricky to do because of the clearance between the frame and the engine. It would have to go around the outside of the frame tube with a heatshield over it.
To make it worthwhile you’d need to open out the exhaust ports as well, take the cylinder bore out to 52mm, fit some higher compression cams, a free flow filter and tweak the fuelling.
After all that work, it would probably return 25-28bhp. Maybe a Kawasaki ZXR250 or Honda CBR250 is a better bet?