Percentage-wise the improvements that can be made to bikes like the Honda VT750 Shadow are much greater than those you see out of a sports bike. Why? Because generally these customs are properly bunged up by the manufacturer to get them through noise and emissions testing…

So uncork ’em –  let the engine breathe freely – and it’s a completely different bike with a whole new life. If we can, we prefer to remap the ECU because the options available to us are so much greater. If we can’t remap the ECU then a Power Commander PC V, as fitted here, will do the job sweetly.

The Cobra pipes fitted to this VT750 were a good start, but because of ’em the engine needed big fuelling mods to get it working with it. So we made some major changes to the fuelling which transformed the engine; the owner was over the moon. As were we!

And shortly after the happy owner – Andrew Morris –  dropped us a note:

“What can I say, it’s like riding a different bike. Not only does it
sound like a proper bike now and not a sewing machine, but the
 performance and fuel consumption due to the dyno tune tops the whole 
experience off.

Fantastic workmanship along with friendly
 customer service.”

Fit a pipe to a VT (and a PC V) and you have a brand new motorcycle...
Fit a pipe to a VT (and a PC V) and you have a brand new motorcycle…

Triumph twins of all capacities respond well too. The owner of this Triumph Bonnie America was a switched on type of chap and as he’d added free-breathing pipes was concerned about his fuelling. He was running one of Triumph’s own maps (to suit the pipes) but it didn’t work for him so he brought it in for a remap.

And it was immediately obvious why once we’d gone and and read the map; it was massively lean. So an awful lot of fuel was needed to sort the throttle response out. One of the main tables that we work in is the switching table between the Manifold Air Pressure map (MAP) and the main throttle position map.

This makes a huge difference because what Triumph (and many others) do is to get the engine to run on the lambda and MAP map, because then the ECU can control the fuelling. When it goes onto the throttle map the rider has a lot more input – this is purely to squeak by the Euro 4 emissions testing.

The result after the remap was like night and day – a very pleasing engine feel and 54bhp at the rear wheel.

Open pipes and a Bonnie America running lean – nothing an ECU remap couldn't fix.
Open pipes and a Bonnie America running lean – nothing an ECU remap couldn’t fix.
Brian's Bonnie fully ECU remapped!

Brian’s Bonnie fully ECU remapped!

We recently ECU remapped the Bonnie SE above and its owner Brian was kind enough to drop us an email with his thoughts after he got home. Cheers mate!

From: Brian Ward

Sent: 29 July 2015 14:06

To: info@bsd.uk.com

Subject: re-mapping

Good afternoon all,

Just got home, after you re- mapped my Bonneville SE. A marked difference in throttle response, better starting, and a slightly deeper exhaust note. A1 service, friendly and helpful.

Would recommend your services to others.

Many thanks guys,

Regards, Brian.