Fitted with open cans, this Moto Guzzi Griso 8V was bought in by its owner for an ECU remap to suit them. We started by downloading the stock map and loading up one of our basemaps for a Griso we did a while back, to see how they compared and which way we’d need to go.
In truth, not well, as the bike we developed that map on was new and this one had done 30,000 miles; it was nice and loose and engines respond differently. Unsatisfied, we put it back on the Dyno, plugged into the ECU and got to work.
We switched off the lambda, which meant the fuelling needed a lot of attention at the bottom end of the rev range and also made some adjustments to the ignition map. The torque maps (which limit torque by various degree through the lower gears) were turned up to give 100% and we then had to match the fuelling at the top end to this change.
The test ride showed that the bike could be better still, so we put it back on the Dyno and focused on the massive dip it had in its power output at around 5,000rpm. The stock 2-1 downpipes are restrictive and their backpressure is holding the engine back at the point where it’s coming up to maximum torque, but we made some fairly radical fuelling changes around the 40% throttle butterfly angle area that instantly produced gains. Out on the road, the improvement was noticeable.
The customer emailed us when he got home; he could feel the improvement and was happy. We were happy too – the bike left our workshop with an extra 6bhp up top, between 5-6000 rpm an extra 9bhp and off the bottom 12bhp more! The dip is still there, though reduced, but with more time could be virtually eradicated.