At a recent Australian Flat Track National (AFTN) training day, the covers came off Jack Miller‘s impressive KTM 450 SX-F, matching that of AFTN Pro 450 Thriller Motorsports rider Billy Van Eerde’s. Both were built and maintained by Hayden ‘Franko’ Franklin of Franko’s Race Shop.
Billy was third in the series just 106 points off the then current leader Mick Kirkness, before the final round at Gunnedah. However, luck was not on Billy’s side, who had a breakout round previously at Brisbane. Billy found himself solidly in the top five all weekend but suffered a nasty crash in race three, ruling him out of the final moto. He ended up hanging on to third in the Championship.
While Billy was out, we thought we’d take a look at his impressive steed with his mechanic Hayden Franklin. This is quite possibly the most intricate build in the AFTN. The Thriller Motorsport 2023 KTM 450SX-F is running only a slightly modified powerplant, with the focus directed at transferring the power to the ground through the 19-inch wheel combination used in the series.
THE MECHANIC
Hayden Franklin
Is this the best flat track build you’ve ever done?
The standard forks are mounted in factory KTM adjustable offset triple clamps and upgraded with a WP 6500 cartridge kit with DLC lowers and Kashima coated upper tubes, while the rear shock gets a bladder kit and preload adjuster. Both front and rear are lowered with a custom setting to suit, giving the bike its overall stance/geometry while retaining that all-important downward pressure to keep the wheels driving into the surface.
The Kullyco AFT spec exhaust, combined with the quick shifter connected and mapped to the ECU allows Billy to seamlessly up shift through the gearbox with maximum power while a Factory WP steering damper assists in keeping the front end stable around the track. All parts and modifications have a strong emphasis on building a complete race package.
To race the AFTN series, the bare basics are 19″ wheels and lower setup bike to correct the bikes geometry with the smaller front wheel, to help with traction down the straight and to retain corner speed, when the rider is on the throttle heavily. These two bikes are far from a basic build though. We are looking to raise the bar and elevate the sport with these bikes and win the AFTN with Billy (Van Eerde).
Jack (Miller) wants to win every race he enters and has the same attitude when it comes to the Thriller Motorsport Team so we went a little further with both the builds to make sure we have fast, rideable and reliable race bikes. The 19-inch Flat Track tyres, depending on the surface type, don’t offer huge amounts of grip, so the focus is more on smooth power delivery and really getting drive regardless of the surface.
FIVE THINGS WE DIDN’T KNOW ABOUT AFTN
- There are six rounds to the series
- Max Whale and Tom Drane (Page 84) made an appearance at the last round
- Four races per round, three rows of a six grid format
- Race are 6-15 laps
- Flat track and TT layouts
For the full feature, check out issue #533 of ADB.
