motorsports |motorcycle modification |new motor bikes |2011 KTM 350 SX-F Long Term Test

Waheed gets into a rut aboard the 350 SX-F at Glen Helen Raceway during an REM Motocross race.

KTM shook up the motocross world this year with the introduction of its 350 SX-F. Like its nomenclature implies, the new SX-F dirt bike utilizes a liquid-cooled, 350cc four-stroke, single-cylinder engine. It’s designed for motocross riders looking for a machine between the current 250cc and 450cc configurations produced by other major motorcycle manufacturers.

If you’ve reviewed out our 2011 KTM 350 SX-F First Ride and 2011 KTM 350 SX-F Glen Helen Impressions review then you’d know how much we love riding it. Over the last two months we’ve put over eight riding hours on it (yes, we know that’s not a lot of time but keyboard duties have impeded our throttle pinning time). We’ve ridden it at a variety of Southern California tracks including: LACR (now closed… read about it in the LACR Motocross Track Shuts Down), Milestone, Pala, Perris, Glen Helen and Starwest.

Everywhere we go it impresses us with its many attributes including intuitive and functional ergonomics, strong brakes, sharp-yet-stable handing and high-rpm engine performance. In fact, the only thing that each one of our test riders agreed upon is that it needs stiffer spring rates in the fork and shock, as well as a seat cover with more grip. Otherwise, it’s almost perfect.

Blowing up a berms at the controls of the KTM 350 SX-F.

So far we’ve haven’t had any problems with the 350. The engine fires up immediately each time the starter button is pressed and all the mechanical parts still function like new. Despite constantly screaming near redline, the engine still feels strong. The clutch, transmission and brakes are also holding up to our abuse without any problems. Even the stock chain, sprockets and hand grips are still in good shape. Though, we have noticed that the wheel spokes become loose every couple of rides. But it’s nothing some time and a 7mm wrench can’t fix.

Maintenance costs have been minimal. We’ve changed the engine oil and filter once (after five hours of ride time) and replaced the OEM Bridgestone soft-to-intermediate tires with the Bridgestone M403 Intermediate Front Tire and Bridgestone M404 Intermediate Rear Tire (available at Motorcycle-Superstore.com) in original sizes (80/100-21 front, 110/90-19 rear). We chose to run full intermediate tires as they are more versatile for the multitude of terrain encountered at Southern California racetracks. We’ve also swapped the air filter a couple of times which is a breeze thanks to the tool-less side panel.

Right before we had to turn return it in preparation for this year’s 450 Motocross Shootout our sportbike and motocross test rider, Frankie Garcia, raced it at Glen Helen Raceway’s main track during a REM Motocross race. Take it away, Frankie:

I can’t believe what a great motorcycle the 2011 KTM 350 SX-F motocross bike is. And that’s saying a lot as I’ve never been a big KTM fan. But after spending a day racing it with REM at Glen Helen Raceway, the all-new machine is one of my favorite bikes to race. I think it could be great for other avid motocross riders as well. So let me now tell you how it all went down Saturday at Glen Helen…

After a nice rain early Saturday morning, we arrived at the Glen Helen just in time for practice. REM usually runs its races on Glen Helen’s smaller track but this time we were getting to ride the main track! After sign up, Adam Waheed and I unloaded our steeds and prepped them with fuel, air (for the tires), chain lube, bled the fork and checked the oil level. After that I geared up and got ready for practice.

As soon as I threw my leg over the KTM I immediately noticed one really cool feature - electric start! With the push of a button the engine is fired and ready to go. Another thing I noticed right away was the well-proportioned ergonomics. The initial feel and comfort of sitting on top of the KTM is spot-on. From its bar and levers, to the bike’s seat profile, it was almost perfect for my 5’ 10” frame.

(Above) The stock suspension spring rates are too soft for most riders above 150 pounds. (Center) Frankie Garcia wrecks during his first moto at Glen Helen aboard the KTM 350 SX-F (upper left). (Below) Just like us, test rider Frankie Garcia immediately fell in love with the KTM 350 SX-F during his motos at Glen Helen Raceway.

When practice got underway I headed out and used my first lap to analyze the well-groomed track and new machine. Once I was comfortable with the bike and saw where the muddy spots were, I put the hammer down. One of the first things I noticed about the KTM was that its engine power was much closer to that of a 450. Plus the handling and overall feel of the bike was more 250-ish. It’s like a dream come true. After practice I really could not find anything about the motorcycle that I disliked. I was having a great time and simply enjoyed riding it. As my first 450 Novice moto approached I began to get a little nervous. I thought to myself, “What kind of start will I get against the 450s? What about the uphills?” I guess I would soon find out.

After arriving to the gate late, I was forced to line up on the far outside. I walked over to my teammate Waheed who was lined up on the inside gates to have a few competitive words with him before the start. I believe the last thing I said to him was, “You watch, I am going to holeshot from the outside.”

Well, I got the jump and thought the start was mine but after clicking into fourth gear the power of the stock 350 wasn’t quite enough compared to the bigger 450s and Waheed just barely edged me out from the inside. I was fourth as we exited Turn 1 and made some quick passes to stay with Adam on his hot rod Yoshimura Yamaha YZ450F project bike. I moved by with an outside pass, but overshot the next tabletop and heard a loud clunk after bottoming the fork. That wouldn’t be anywhere near the last time I did it either.

About a half a lap later I made a mistake around an off-camber uphill corner and high-sided, landing on my head. Good thing I was wearing a Bell MX-1 helmet. Within seconds I was back in the race (got to love electric start) and was trying to chase down Waheed. I took a crazy line for a pass attempt through a rough part of the track, but the fork bottomed in some braking bumps resulting in the handlebar swapping and slamming into my stomach. With the wind knocked out of me I called it quits in hopes of getting some rest before Moto 2.

The REM crew does a fantastic job of pumping out motos quickly so I only had a small amount of time to regain my composure and make some suspension adjustments to the bike. I decided to try and tweak the shock to help with some rear end traction and stability. I softened the high-speed compression by a half-turn, softened the low-speed compression by two clicks, and sped up the rebound by two clicks. Making these adjustments gave me some much needed confidence for the final moto after taking a pretty nasty digger in Moto 1.

As the gate dropped, I got another awesome jump but was just edged out by a couple 450s, one being Waheed. Darn it! After my Moto 1 DNF I really wanted to win. I stayed behind Adam for a couple laps figuring out his weak spots and soon found where I would make the pass. I squared up the corner before one of the monster uphills and passed him on the inside. Would it work? It did with both of us motoring uphill right next to each other.

I kept the throttle pinned to the stop, leaned back and the 350 pulled side-by-side with Waheed’s built 450. Full of excitement, on the way back down I carried too much speed trying to be a hero through the braking bump and bottomed the fork again. Thankfully, with its fantastic brakes I managed to slow down enough to make the inside rut. After leading Adam for a couple laps my stamina came into play and I began to run out of juice. Soon enough he was on my rear wheel and after taking his pressure for a little while I decided to let him go. To my surprise just after I let him get by he made a bad line choice of one of the hills and lost momentum and stalled out giving me the easy win. I would end up with DNF-1 scores for the day.

KTM 350 SX-F Maintenance Costs

Months in Service / Total Run Time: 3 / 8 Hours
MSRP: $8499
Aftermarket Accessories Cost: $64.95
Maintenance Costs: $180.30
Parts Breakdown:

(1) Dirt Digits M10 Backgrounds: $64.95
(1) Oil Filter: $11.33
(2) Motorex Oil (Liter) 10W-40: $39.99
(1) Bridgestone M403 Front Tire: $62.99
(1) Bridgestone M404 Rear Tire: $65.99

Overall I am very happy with the KTM 350 SX-F. It is an outstanding motorcycle and is definitely competitive with the 450s. The bike’s engine power is outrageously smooth, yet it pulls forever. The suspension is definitely on the soft side up front and could use some springs for sure, but the shock was better. The fork valving seemed to be pretty decent - plush and smooth – but the WP just could not handle big holes during braking overshooting jumps. The rear shock absorber played a huge role in the bikes great handling, it took a lot of heat and the rear of the bike was planted after I made some adjustments. The braking system is excellent with some serious stopping power but is not too touchy like previous models. I’m also in awe of just how well-designed the ergonomic package is. It immediately offers comfort and confidence to the rider. My only other complaint would be that the seat could use a little more grip but with a quick installation of an aftermarket seat cover that problem can be solved very easily.

Make sure to keep your eye on Motorcyle-USA.com in the next few weeks as we find out how the 350 SX-F compares against the rest of the 450s, including its Austrian sibling, in the upcoming 2011 450 Motocross Shootout. Additionally we will be compiling more long-term test updates as we accumulate more hours on it.