2016 KTM 350XC-F

Introduction

• 350cc bikes are a blend of power and lighter weight, perfect for lots of off-road conditions.

The 350cc four-stroke is nothing new. But is it viable. KTM sells more four-stroke bikes in the 350cc displacement size than any other. Even without a dedicated displacement-based racing class for the size. It is like the 400cc four-strokes before it, the size has a magical trait of low-end torque and high RPM horsepower without the weight penalty of larger sizes. With the better technologies, materials and systems only 350cc is needed to get what took much more displacement before. And KTM keeps pushing the development basically making an all-new engine for the SX-F and additionally for the XC-F too. Wrap that motor in the latest and greatest chassis KTM has, throw a few off-road racing goodies in its direction and you have a machine that breaks molds and sets standards. We know the bike is good but how good is it and who is this bike for. Dirt Bike Test set out to answer those questions.

Changes

• All new and based off the Factory Edition SX machines.

The 350XC-F is all new from the ground up. This could be called a Factory Edition off-road racer since it’s base is the pure SX-F motocrosser in every way that is needed. The chassis is a newly designed Chromoly steel design that is lighter providing more torsional rigidity and less longitudinal stiffness. The aluminum subframe has a matching smaller profile. The swingarm looks familiar externally but it too is revised with a new internal structure. Even small details like the footpegs were completely redesigned to be lighter, more grippy and very thoughtful in the way they keep dirt from clogging anyplace in them, including the pivot. The triple clamp now features rubber mounted bar mounts and allows adjustability for different rider sizes and preferences.

On the suspension side the XC still uses the WP 4CS fork with revised settings to improve the plush feel. The rear shock rides through a new linkage ratio and is valved to work with all the changes in the chassis. Both ends of the suspension are set up specifically for off-road racing. Some small bits that show attention to detail are the ODI clamp-on grips, Galfer wave rotors, Giant rims and Dunlop AT81 tires. Of course the plastics are all new in design and there is even higher function here. The radiator louvers are shaped to force more air through the radiators with a tighter fit. The air box is not only sealed better with a tougher cover but the clamping mechanism for the filter is basically foolproof using a pin design for locking. On the XC there is the 2.25-gallon translucent fuel tank that is hardly wider than the SX tank. An aluminum kickstand and handguards are standard too.

The engine is much smaller in physical size and drops a few pounds in the process. Without a kick-starting attachment, everything got more centralized to reduce the rotating mass feel and make it more compact. Running a 44mm Keihin throttle body controlled by a new engine management system that includes launch control internally but does not include the button to activate it, see your KTM hard parts for that. The top end is all new too, especially the cylinder head and all its pieces. The piston is a CP bridged-box design attached to a shorter and stiffer connecting rod. The gearbox is a six-speed semi-close ratio design, up a speed from the motocross bike.

Power

• A very lively engine character that revs for what seems like forever.
• Very reluctant to stalling as long as the throttle isn't closed.
• Great clutch control and a well spaced transmission that lets the bike pull to over 100MPH.

Just how do you describe the KTM 350XC’s power? Lively is a word that keeps popping up. It would be too easy to say the power is a cross between a 250F and a 450F, even though that is very close to what a 350F really is. But with KTM’s improvements to the engine, it is blessed with a way more 250F lightweight feel while putting out some very impressive power way up on top. Yes, it now revs like a 250F.

Off of idle there is a noticeable decrease in the flywheel feel that you might confuse as torque. This motor will stall out easier with zero throttle and we found setting the idle rather critical on this bike to get the best performance down low. (see http://dirtbiketest.com/fresh-dirt/ktm-throttle-body-tuning/ ) But it has plenty of torque and more of it as you open the throttle. Not chuggy and feeling the piston going up and down—now it is a blended and smoother delivery of power with a pick-up that is impressive. It makes the older 350 XC-F feel sleepy and the current 350 XC-W and EXC feel sleepy and slow. And the power picks up what can be described as exponentially when compared to other motors. The more RPM, the more power. Super high RPM, way more power. As much as you can stand ringing this motor out it can keep on delivering power so you soon really learn to rev the bike to get the most out of it. 12,500 RPM is peak power but the bike pulls cleanly for at least another 1000 more. Putting the spinning stuff closer together and making it lighter has paid off in how light the bike feels when it is singing.

The spread is very long so working in a single gear without shifting becomes a reality more than just about any other bike we have ridden. Once the idle is where you like it, the FI is spotless and even where it feels as if this bike should not function, very large throttle openings and low-low RPM for example, it keeps chugging and will pick-up without much clutching. First gear isn’t the lowest but it is low enough for anything you’d encounter in a GNCC or a GP. Not to say that adding a tooth or two on the rear would hurt anything. Our bike went a GPS indicated 105.6 MPH on a dry lake bed! The gear spacing is wide enough so that you feel the shifts but never wide enough to have a gap. Compared to SX the XC starts out with a first gear that is ever so slightly lower and then second gear is just a bit taller. Then it progressively gets a little bit higher in each ratio so that even fifth gear is higher than the SX and you have the sixth speed to spare. If you feel anything on the track it is that the second to third space is longer than a true MX bike.

The clutch is really good in feel and durability as long as you don’t abuse it. It is a conventional coil spring (6) design now. We were riding on a sand track and pulling out of turns pretty close to two gears high in some turns and the clutch let us know it was getting hot, trust us, it was definitely abusive and the warnings were obvious. Riding in the proper gear allowed it to cool without ever stopping.

The lack of a kick-starter has some concerned, not us. The bike started every time we wanted it to but sometimes it can take a little more cranking than we were used to. For some reason 350cc bikes do not seem to be the best at firing quick. The Lithium battery will crank the bike just fine but on cold mornings it needs a quick push of the button and a few second wait to allow the battery to self-warm. Also, setting the idle properly helps this especially when the bike is hot. And then there is the exhaust note. As a competition bike it is average but for off-road it is a little on the loud side. The canister on the header is said to help power and noise a little and these chambers are now common.

Suspension

• The WP 4CS fork is improved in plushness beyond what we though was possible.
• The XC-F will handle motocross right up to the point of steep jump takeoffs and still have manners on the trail.
• With adjustments you can shift the performance in either direction (more or less aggressive)

We have beat up the KTMs riding on the 4CS fork a little bit (not as much as some because we found ways to get past the harshness) and we were very surprised by the suspension on this 2016. Whatever WP and KTM have done inside the fork has really worked and changed the harshness feel of the fork specifically and onto the chassis feel of the bike overall. It is still a unique design and the adjusters and the results of what they do may not be familiar, but the suspension is really pretty spot on for the bike’s intended purpose.

For starters and for off-road this bike rides stiff, as it should. It is almost motocross stiffness but not quite. Stiff enough to hold the bike up tall in the stroke but not so much that the wheels will chatter on the ground on rocky or rooty conditions. Here the break point where the fork and shock start moving is a little less than a MX bike but nowhere near how soft, plush and springy a EXC, XC-W trail type bike would be. The ride is stiff so you can feel what the tires are touching just short of beating up the rider. Even on a motocross track the bike does not feel soft. In bumps like whoops and on jump faces, the bike uses the travel and does not bottom much at all. It takes a pretty strong hit to get a good clank out of either end. It does not get harsh, have stiction or react poorly in the mid-stroke like previous 4CS forks did.

In testing we did not play with the clickers much from standard as there were very few complaints. On tighter trails backing out the compression on the fork had mixed results and we actually found running the compression and rebound a little stiffer made the bike act softer in the smaller bumps. Here is where you have to think differently about the way the 4CS fork reacts. The clickers seem to act more on the mid-speed valving and in turn affect more of the riding height of the fork. Stiffer has it riding higher in the stroke and in a softer part of the action.

On the other hand the shock is very conventional and seems to be working better than ever as well. On trails we softened it a click or four and at the track we did the opposite. Our ride height settled at 103mm for the best in handling and shock performance. With its softer front spring in the fork compared to SX and the same out back a lot of the difference in ride comes from the valving which is just plain more progressive. Additionally to counteract the downside of the softer front fork springs the oil level is set higher to combat bottoming too.

Chassis - Handling

• The light feel of the KTM while riding contradicts convention with the high power output.
• A very roomy layout for such a compact bike.
• The chassis transmits the feel of the ground to the rider, not the most comfortable but effective for racing.

The handling department is what the 350 is all about. It is the lightweight feel combined with decent torque and horsepower as a unified, or as some people prefer a “perfect” package.  Scaling in at 242.2 pounds with a full tank of gas (229 lb. empty) the XC-F is a very light bike. Nearly as light as some 250cc four-stroke motocrossers. And it feels this way no matter what. Truthfully the biggest improvement from the previous model is how much lighter it feels all the time, and especially when riding the bike hard high in the RPM range. It doesn’t gain the weight that usually comes with the power. It is the sensation that factory 450cc motocross bikes are so sought after for and that takes a lot of very expensive and rare metals inside the motor.

Being a smaller bike overall it is amazing that the KTM still feels as roomy as it is. Maybe not as spread out as they were a few years ago but it is far from cramped. With that smaller feel comes the lighter feel too, thin as well.

When going fast in tighter conditions this maneuverability is where a 350 will outshine any bike and this KTM excels. It has the ease of rideability since the power spread is so long, letting the rider largely ignore shifting or the clutch. It likes to turn on the front wheel but will just as easily slide with a little extra throttle. The bike can be set up to ride a little higher in the rear or a little lower in the front and the turning will only get better until there is a loss of stability but it is obvious when you have gone too far. Another area of praise is when the bike is under acceleration the power is just fast and hard enough to drive the bike forward without being too much and trying to lighten or lift the wheel when unwanted.

Then in faster conditions it is amazing how stable the bike stays for turning so well. There isn’t any headshake to speak of. If there were any complaints and maybe these may be complements as well, the XC-F has that two-stroke light on its tires feeling. This makes the bike feel like it is dancing a little bit as opposed to being rock solid planted to the ground like a 450cc four-stroke is. But what the 350 does is use its compression braking on deceleration where the front end really sticks in the turns like no two-stroke we know of.

The chassis has a stiffer nature to it but the rubber-mounted bar clamps take the sting out of the handlebar. Riders can feel a little of this in the footpegs, which are excellent at gripping the boot and cleaning in the mud. As is common on the KTMs the brakes are strong and have great feel and get better in feel as the rotors break in.

Working on the KTM is relatively simple and the basics like oil changes and air filter (no tools) is excellent. We don’t know for sure about the durability of the new bikes but we’d suspect they will be excellent as we have come to expect. KTM did take a few measures inside the engine to increase the service life of the crankshaft so we know they are thinking about it all the time. But any time the weight drops you end up with what some people like to call less motorcycle. We’ll keep an eye on it but in over 12-hours on the bike, none of them very easy on it, it has been perfect and the oil came out very clean. Our only issue was a slight oil leak out of a set screw in the ignition side cover which was fixed with a little sealant on the screw.

Some of the KTM niceties include the easy adjust brake and clutch levers and the adjustable two-position of the handlebar clamp. The design of the front number plate also includes the flap to hold the brake cable integrated, which is sano and clean. The plastic has proven strong in our occasional tip-overs and the impregnated graphics, which are very plain Jane, do not come off. The O-ring chain is excellent for stock equipment as is the chain guide and chain skids. Handguards keep the small branches at bay but will fold if asked to bust bark or protect levers in a crash. The bar pad is big and proper though. We added a KTM hard parts skid plate and swingarm protectors after our initial photoshoot to keep from destroying the bike in our desert rocks and it was a smart move. We wish we would have had the ignition position switch on the bike since we had a chance to try it at the initial press launch and it can really alter the character of the engine for different conditions.

On the left side of the fuel tank the fuel hose sticks out into thin air and looks like it could get damaged in a crash or by branches or aggressive roost. And there is the locking push-to-open gas cap which is a love it or hate it affair for most, depending on the temperature.

Conclusion

• This is a "one bike can do it all" machine without much compromise.
• It is a skidplate away from the starting line for GNCC or any off-road race really.
• For average motocrossers the XC serves up an excellent track performance, yes even compared to SX.

Now in riding there is always talk of compromises. The 350 size has its obvious advantages and disadvantages. But KTM has chosen to go after the weight side of the equation and has succeeded in spades. The bike feels light like no other 350 can claim, light like a 250F motocross bike with power coming out of the muffler! The jump year-to-year is pretty huge but if you go back just a few years the transformation is amazing. Where the 250F’s have had to become more focused on peak power, this 350 has broadened its horizons on all accords. More power and torque with less weight feel and a handling and suspension that works in a wide range of conditions.

The 2016 350XC-F has very few--if any flaws. As an off-road racer it is on point, as good as it could get for a stock bike designed to work for wide range of riders. You can take it trail riding and it has enough manners, way more than any motocross bike has, to make the ride pleasant, not just tolerable. You can take the 350XC-F to the track and get with it on anything short of supercross-type obstacles.  Plus it isn’t going to give up much to any other size displacement, especially on tighter circuits. If you are looking for one bike to do it all on and your definition of all is really far reaching, fast stuff and tight and technical alike, this KTM is calling your name. It isn't cheap but you are not going to do it any other way for less either.