How We Develop Our Motorcycle Remaps

Every BHP UK motorcycle remap is written in-house by our own map writers. We run the bike on our Dynojet 250i dyno, fit our own lambda sensors to measure the air-fuel ratio, log the engine in every riding mode it has, write the map, and then road test it so it works in the real world.

In short

All our bike remaps are developed in-house. We don’t use base maps from other companies.
We develop on our own bikes, so we can take the time we need and test modifications properly.
Each bike runs on our Dynojet 250i with our own lambda sensors and external sensors logging the engine.
We log the bike in every engine mode it has before we change anything.
Every map is road tested after the dyno work.

1. We start with our own bikes

We tend to do all our development on our own bikes. As our Harley-Davidson page puts it, we do our learning on our own machines, not your pride and joy. It also means we can spend as much time as we need to get the data we want, and test different modifications to understand how they affect the way the engine works. And because we’re all petrolheads at BHP UK, our development bikes double as a fleet we ride and test at weekends.

2. Running the standard bike on the dyno

Development starts with the bike as the factory made it. We run it on our Dynojet 250i and measure its power output, while our logging equipment watches how the engine is working.

3. Logging the engine

Power figures alone don’t tell you how a bike has been set up, so we monitor every aspect of engine function we can. We attach our own lambda sensors to measure the air-fuel ratio, and we also log:

throttle position and throttle plate position
spark advance
knock detection
engine oil temperature
engine coolant temperature
exhaust gas temperature
injector duty cycle

Some of these we can log through the bike’s on-board diagnostics. Others need external sensors with analogue outputs. On our BMW R1200 GS we also logged injection time and lambda at different twist grip positions, repeating the runs at each one.

4. Every riding mode

We run and monitor the bike in all the engine modes available, which gives us a complete picture of its standard mapping. The R1200 GS has four modes, Road, Enduro, Rain and Dynamic, and we repeated the whole process for each one. It takes a lot of time, but it shows exactly how the factory set the bike up and where we can improve it.

5. Finding the restrictions

The data shows us how the manufacturer has set the bike up and where improvements are possible. On many occasions we find that the manufacturer has restricted throttle opening or imposed torque limiters in the mapping to soften power delivery.

6. Writing the map

We write the map into the factory ECU, so we can adjust any engine parameter we need to; what is motorcycle remapping? lists them for a Harley-Davidson. On our Iron 883 we changed the fuelling at every throttle position, so power delivery stayed smooth and progressive through the rev range.

Because we write all our maps in-house, we can custom tune them for your modifications, such as an aftermarket exhaust or air intake. See Do you need a remap after fitting an exhaust?

7. Road testing

All our remaps are developed on our rolling road and then road tested, to make sure they work in the real world and not just on the dyno.

Results from our development bikes

Two of our development projects are written up in full, each with a video of the work.

Bike	What we did	Result
BMW R1200 GS	Logged all four riding modes, then remapped	Smoother power delivery at throttle openings up to 80%; 118bhp to 121bhp at the back wheel at full throttle
Harley-Davidson Sportster Iron 883	Aftermarket exhaust, open air filter, remap and dyno set-up	Wheel power from 43bhp to 56bhp; peak torque from 47 lb ft to 52 lb ft

The Iron 883 also shows why the remap matters. With the new exhaust fitted, the engine ran very lean and the air-fuel ratio reached 18:1 at points. The bike would not have been safe to run without the correct remap, and if it hadn’t been our own development bike we would have stopped the dyno run.

You can read more on our Harley-Davidson and BMW Motorrad make pages, or look up your own bike in the motorcycle remap finder.

Getting the map onto your bike

You can bring your bike to our workshop in Burnley, Lancashire, load the map yourself with an ECU Flasher, or send us the ECU: Remap your bike at home with the ECU Flasher explains each route.

Talk to us

Call 01282 779 000 to talk about your bike, contact our Burnley workshop or find a local BHP UK dealer.

Frequently asked questions

What dyno does BHP UK use for motorcycles?

We use our Dynojet 250i to run the bike and measure its power output while we log how the engine is working.

Do you use base maps from other companies?

No. All our remaps are developed in-house by our own map writers. We do not use base maps from other companies and simply tweak them to run on your bike.