KTM has quickly has become the leader with the way an off-road motorcycle manufacturer should advance technology in only just a few short years. KTM is producing quality production motocross machines that are consistently in the hunt to be on the top spot in our 450 MX Shootout and pushing the envelope when it comes to thinking outside the box. The WP 4CS fork has held the 450 SX-F back from its potential in the past, but now that KTM has gone away from that style of fork, we could see the orange machine reign supreme in the big bore MX class for 2017. KTM engineers made a few key changes to the 2017 KTM 450 SX-F from the 2016 Factory Edition model: The big changes are the 48mm WP AER fork that replaces the atrocious 4CS design (that saves nearly three pounds), the top triple clamp is slightly more rigid to help the SX-F corner more precisely, the outer fork tube thickness decreased 1mm for increased flex in the fork, updated handlebar mounts that are slightly stiffer, aluminum head stays (instead of steel), a softer rear shock spring rate, and a multi switch handlebar mounted map and traction control switch. Yes, that’s right traction control! We spent a couple days aboard the orange pumpkin and wanted to let you in on what we felt about some of the changes KTM made.
A smooth roll on type of engine character that builds into a huge mid to top end pull is what the 2017 450 SX-F’s engine is like to ride. You’re not going to get as much excitement down low like you will from a Yamaha, but what the KTM lacks in excitement down low certainly makes up for it through the middle to upper parts of the rpm range. If the track is disked up really deep or if there is heavy sand, the bottom end might feel lazy and somewhat lethargic, but once the track breaks in you will be glad you have that smooth transition into the mid-range. Mid-range is very useable and quite wide with excellent rpm response through 7000-8500 rpm. The air fuel mixture on both maps (1 and 2) seems to be really clean through the middle part of the KTM 450 SX-F’s power. If you like to rev your machine the KTM 450 SX-F is the only big bore motocross bike that will allow you to get away with this. The KTM will pull so far on top end and rev out almost like a 250F would. It literally feels like it revs a couple thousand rpms further than all 450 contenders. We did notice one small hiccup in the KTM’s armor however. Second gear seems very short on the tracks we tested on. Running second gear through corners felt too low and shifting to third felt too high. We ended up just lugging the bike more around the track, but felt it could get into the meat of the power sooner with a gearing change. The 13/48 gearing is not quite right to us, so we will be trying different gearing selections to see if we can remedy this. KTM engineers really seem to be getting the vibration down on these engines they are producing. Even when riding at high rpm’s there is almost no vibration going through the rider’s hands or feet.
Map Switches/Traction Control:
The on the fly map switches are really cool and the traction control is very effective. We normally ran map switch number one (standard) as it produced a longer power, which most testers preferred. Map switch number two gave the KTM 450 SX-F a little more bottom-end, but it wasn’t enough for us to warrant the shorter top end pull that was felt with this map. Traction control came in very handy around the two baked out, dry, Southern California tracks we tested at. With the TC on, the KTM was easier to handle as the track became rougher and turned slick in the afternoon test sessions. Flat tracking around corners that had nothing for the machine to push against let the rear wheel bite down and rear end squat giving the rider a planted feel. We kept the traction control button engaged most of the time late in the day and the KTM still had enough motor to pull us over every sizeable obstacle the track had to offer. The action of the suspension was also improved with the traction control engaged (late in the day on a dry, rough, blown out track) as the orange machine stayed planted to the ground (not letting the rpms get too high on the slick, dry surface) preventing the suspension from binding up.
Usually this is the part where you cringe, skip over, or even close your eyes when you get to the KTM’s suspension evaluation. Well do not fret, as the KTM 450 SX-F’s suspenders are not frightening in 2017. Is the WP AER fork as good as a KYB SSS fork? No, its not, but it’s actually the best air fork that comes on a production off-road bike to date. The 48mm WP AER fork actually moves in the top of the stroke. On acceleration bumps where the fork is light and in the top of its stroke the fork is plush and will not deflect. Mid-stroke harshness that plagued the WP 4CS is not as apparent with the AER fork. We ran the fork around 10.6 bars to start with and that left us with a fairly comfortable ride at the end of a longer 35-minute moto. When we say “mid-stroke harshness is not as apparent” as the 4CS, we are saying that there is a little harsh spot through the middle of the fork, but nothing compared to what we get with the KYB PSF2 or even the Showa TAC fork. We do however bottom the fork from time to time on steep jump faces or on the occasional over jumping situation. Most of our testers could live with this little bottoming nuisance versus having a fork that is so harsh; it would force you to ride slower lines, instead of just hitting the bumps. With the AER fork you can actually hit the sometimes rougher, shorter, faster line when entering a corner. The WP shock had a happy sag setting between 106-107mm and tracked very good out of corners. It too is a little soft for aggressive riders over 180 pounds, but stiffening the high speed compression a quarter to half a turn really helped hold the rear up on jump faces. With the front end improving on the 2017 KTM 450 SX-F it really helps the balance of the bike around the track. We are going to experience more with the fork settings as the week’s progress, so look for updated settings soon.
This bike feels light! It feels like a 250F in the air and mid corner the KTM 450 SX-F really lays down nicely. We did have a little hinge feeling in the front end on initial lean. It felt like the bike was hinging near the head tube and would release once inside the rut. What we mean by “a hinge” is, as you would start to lean the bike into a corner, there would be a heavy feeling, and then it would release/flop down into the corner nicely. We are going to experiment more with the fork settings (trying to get better hold up) at different tracks to see if this might help that feeling. Straight-line stability is impressive for such a light, powerful machine. We really like how the rear end always feels connected and doesn’t react too much (side to side movement) when clicking fourth gear through deep rolling whoops. Since KTM updated the frame in 2016 the chassis feeling on square edge, choppy tracks keeps getting better.
Other tidbits we noticed on the track is that the middle part of the KTM (shroud area) has a spot where some testers legs got hung up through deep ruts. The upper part of each shroud has an area where it bows out slightly and that has been getting riders knees/boots hung up somewhat. The ODI grips are a nice touch and easy on the hands when putting a lot of time in the saddle.
We will be getting more hours on the 2017 KTM 450 SX-F to see if we can tinker and improve on what is already a very good package. We asked for a better production suspension package from KTM and we received it. Could this be the year of orange in the 2017 450 MX Shootout? You wont have to wait long to find out!