KTM RC390 Street To Track: The Conversion Begins!

The folks at KTM would not sell me the AMA KTM RC390 Cup bike that is a race ready package. These kitted Cup bikes were restricted to racers under 22 years of age who would race it in the USA. Besides the fact that the Cup bike was about double the price of the street bike, I am neither under 23 nor interested in racing in the USA. This meant I could not buy the “ready to race” bike. I bought the street version instead and started the conversion from street bike to road race bike.

My KTM RC390 arrived at Mission Cycle in Angus Ontario in late April. After doing some break in time on the street, the bike started its conversion into a road race bike. We started by having Mission Cycle have a look at setting up the suspension “sag” to my weight. I am of course more svelte than any photos of me might lead you to believe. “Sag” is important as a starting point for any suspension tuning of a bike. Setting the sag is not just for suspension experts. Go online and there are lots of “how to” videos on setting sag for your motorcycle.

My plan to road race the RC390 meant that I had to remove all of the street stuff. Off came the mirrors, signal lights, headlight, tail light and licence plate brackets. This stripping process took about a day in the shop. I labelled all the pieces with where they go on the bike so that someday it can be a street bike again.

I found that there was no available racing bodywork for the RC390 so the stock bodywork is staying on it for now. The mostly uncomfortable looking rear passenger seat actually looks like a racing tail and will stay on the bike for now. I was able to buy a few of what KTM calls “Power Parts” for the bike. I got a racing only front windscreen that looks like the stock screen but has no opening for the headlights. I also got a Power Parts bellypan. A bellypan is required for racing as a blown up motor could “oil” a track. The bellypan prevents engine oil from getting onto the rear wheel or the track. Oil inside the bike = good. Engine oil outside the bike – bad!

While the stock street (under engine) exhaust system is neat and effective for a street bike, it won’t do for a road race bike. After a considerable amount of time spent getting the exhaust “box” off, I was able to replace it with an F1 Fuel Racing system from the UK. KTM sell an Akrapovic system for the KTM which is really nice. However, it is also very expensive and had questionable availability. I went with the Fuel as it was already available and about half the price. The new exhaust mounted up without too much grief in about 2-3 hours. It is all polished stainless steel and looks great. But holy crap, is it loud! Now boys and girls, it is important to remember that a change on any bike to a free flowing exhaust requires some changes to fuelling. With carburetors it means a richer set of jets. With fuel injection like the KTM, it means re-programming the bike’s ECU. If you don’t do this the bike will run really lean, this in turn will cause the bike to run hot to very hot. Too hot and it shuts down.

So this meant a return trip to the dealer. Todd at Mission Cycle had his team change the ECU program in about an hour. No, you can’t do this at home, unless you have a programming add-on module like a Power Commander or Pazzazz unit.

My plans to race the KTM mean I will be removing the ABS brake system. This requires new brake hoses and an afternoon spent removing the ABS sensors, ABS wiring and the ABS controller. When changing brake hoses, be careful as brake fluid will ruin paint. After the stock brake lines were replaced with a set of new lines, the system required “bleeding”. This is the process required to get the new brake fluid into the system and to remove all the air in the lines. Air in the braking system makes a “mushy” brake feel. Air left in the system can also be a major problem if not removed. Again, there are lots of on line videos on how to bleed your brakes. Production racing rules mean I can’t switch to a radial type handle master cylinder for the front brake or change to a bigger FR rotor.

A word on brake fade; brake fade is when your brake pads and fluid get hot (ok, really hot) and don’t stop as well as they did when cold.

Normally, the next race mod would be replacing the street bike brake master cylinder. I decided to leave the stock master to comply with production racing rules.

A set of Pirelli Super Corsa sticky tires replaced the stock street tires. These tires are street legal and about as sticky as running slicks.

The next required change was to mount a belly pan. Fortunately, Mission Cycle was able to obtain one of the KTM Power Parts belly pans designed for the cup bikes. Belly pans are required to ensure any engine blow up doesn’t result in oil getting on to the track or your tire!

Racing organizations don’t like oil on the track or antifreeze. So all antifreeze has to be drained and replaced with water. Next comes the long and tedious task of drilling fasteners for safety wire. Again there are lots of Youtube videos on how to drill fasteners and then use stainless steel wire to ensure the nut or bolt is secure. Trust me, it is a long, tedious process, but necessary.

Take a look at my first post in my KTM RC390 series here...

My next post...

Flashing isn't Porn: KTM RC390 ECU Upgrade

Your comments are welcome.