The Portsmouth-based owner of this fuel injected 2006 KTM 990 Adventure (fitted with Akrapovic cans) was quite succinct in his request to us; “Look mate, it’s sh*t, if you can’t fix it chuck it in the skip.” To be honest, we didn’t think it could be that bad, so we rode it. Shutting off for a roundabout, tapping it back on gently to go one way the bike took off of its own volition – the throttle was so off/on with nothing in between, and sitting at a constant speed was nigh-on impossible, especially in traffic. The bike’s owner, it seems, was bang on!
On the dyno it went for a full sort out and ECU remap. We’ve done a few SMT 990s now but this was the first Adventure we’ve strapped on for this treatment; the plan was to take our time, unpick the engine management bit by bit, and build a fully sorted map for the bike as per the customer’s request (which was to make it rideable).
So we did just that. There are several reasons that these big KTMs behave as badly as they do at low speeds and part throttle openings; firstly, the MAP (Manifold Air Pressure) sensor is responsible for the ‘hunting’ in the mid-range, around 3-4,000rpm, when it’s essentially switching back and forth from the MAP map to the main map. But the snatchiness, the on/off throttle is directly down to an extremely aggressive ignition map added to the unnecessary input of the secondary butterfly valves. We spent a lot of time building an overall map for this bike, via our RexXer, Dyno and computer that effectively neutralized all of the negative effects so obvious out on the road.
The job in hand here was to make this bike an enjoyable prospect to ride. The requirement wasn’t for outright horsepower, and we’re not altering anything to do with the engine’s configuration, such as cam timing etc. Purely by remapping the ECU the net result is as follows;
1) You no longer have to think about the throttle, you just ride the thing, in an old-fashioned ‘analog’ style fashion.
2) It’s gained 7bhp in the midrange, and pulls like a train…
3) …but has lost 4bhp right at the very top end.
The owner, when he came to pick it up (before he put it in his van) took it around the block for 15 minutes. When he got back, he was beaming ear to ear and all he could say was “It’s a miracle…!” Our skip remains untroubled.