2011 TM MX300 TWO-STROKE MOTOCROSS TEST: A BIG-BORE TWO-STROKE MOTOCROSS BIKE WITH ITALIAN FLAIR

As it sits, the TM MX300 competes for attention against the KTM 300XC, Husqvarna WR300, Gas Gas XC300 and kitted YZ250s and 250SXs. As a rule of thumb, the extra 50cc is worth three horsepower over its 250cc loaner engine


2011 TM MX300-2T Cross: TM doesn’t just buy parts from outside suppliers. They try to build as much of the MX300 as possible at their factory.

Q: WHO BROUGHT TM MOTORCYCLES TO AMERICA?


A: Way back in 1994, Pete Vetrano was at the Trask Two-Day Qualifier when he spotted a three-man team of wily ISDT veterans riding full-size TM 80s. At the time, Vetrano was importing Italian motocross products and asked his Italian friends to introduce him to the people at TM in Italy. Late in 1994, Vetrano signed a deal to become the U.S. importer of TM motorcycles. In his first year, Pete didn’t sell very many bikes (because they were delivered late in the 1995 season). But over the next five years, TM USA increased their sales to over 200 TM motorcycles a year. That may not sound like much, but selling 200 exotic motocross bikes in a single year is a major accomplishment.

Q: WHY DID TM MOTORCYCLES GO AWAY IN 2005?

A: In 2005, Pete Vetrano’s TM USA company was faced with the daunting problem of a falling dollar, a strong Euro and mediocre TM four-strokes. Pete threw in the towel. The Italians quickly found another importer, but sales fell so far that they virtually returned to where they were in the first year of being imported. Things looked grim for the future of TM motorcycles in America. In fact, after the second U.S. importer failed, the only way to get a TM was through the Canadian distributor (and they weren’t very good at cracking the American market).

Q: HOW DID TM MOTORCYCLES COME ROARING BACK IN 2011?

A: At last year’s USGP, the Italians, led by Gastone Serafini, ran into Pete Vetrano in the pits. Neither party was being coy, and before long, TM asked Pete Vetrano if he would become the importer again. A few months later, the two sides met in Milan to work out an agreement. Vetrano gave TM his proposal. TM countered with a proposal of their own. In the end, Pete Vetrano said, “We compromised on an agreement that neither of us was happy with, so it was probably a fair deal.” TM is back, thanks to one man who can’t call it quits...even after calling it quits six years earlier.

Q: WHAT IS A TM MOTORCYCLE?

A: TM is an Italian boutique brand that was founded in 1977 when two friends joined forces to build a motocross bike. One, Claudio Flenghi, was a talented kart-engine designer and the other, Francesco Battistelli, was a motocross racer. The two friends left their jobs and founded TM motorcycles, and they are still in business today in their Pesaro, Italy, factory. The TM factory is more like a four-story race shop than a motorcycle plant. Visitors get the impression that TM is all about building high-end racing motorcycles—and that selling them is an afterthought (that pays the bills).

Kart: TM’s two-stroke powerplants are famous in karting.

Q: IS TM A TWO-STROKE OR FOUR-STROKE MANUFACTURER?

A: Originally, TM was a two-stroke company based largely on their World Karting Championship engine designs. But, in 2005, they built their first four-stroke engine. Today, the TM line is equally split between 85cc, 125cc, 250cc and 300cc two-strokes, and 250, 450 and 530 four-strokes.

Q: IS THE MX300-2T CROSS ENGINE FAST?

A: Yes. That is a fairly simple answer, given that 300cc two-strokes tend to hit the sweet spot of two-stroke horsepower and torque. As it sits, the TM MX300 competes for attention against the KTM 300 (XC or kitted 250SX), Husqvarna WR300Gas Gas XC 300 and aftermarket 300c YZs. As a rule of thumb, the extra 50cc is worth three horsepower over its 250cc loaner engine. The 300cc can make more horsepower, but at the same time have a torquier and more manageable powerband.

Pulse: The power surprised us. We expected a torquey enduro-style power. Instead, we got a 250 powerband on steroids.

Q: WHAT IS THE MX300-2T CROSS POWERBAND LIKE? 

A: Here is what the MXA wrecking crew expected from the MX300-2T Cross engine: (1) More low-end grunt than its 250cc brethren. (2) A broader and healthier midrange. (3) Less top-end over-rev (because the same stroke as the 250 engine would be pushing a much larger piston). What did we get? Not what we expected. The TM MX300-2T was fast...very fast. It didn’t have the low-end grunt that we thought would come with the big piston. Instead, it hit like a country mule in the midrange and took off like a scalded cat. Need more animal references? It would propel itself into action like a charging rhino and flatten on top like a flounder burying itself in silt. This wasn’t a casual, big-bore trailbike with a lackadaisical approach to making power; it demanded your attention, a quick clutch hand and a willingness to go for broke. The MX300-2T engine rewarded talented riders with all the midrange power they could ever want, but punished the maladroit with its tricky low end and flat top (we expected the top end to be flat).

Q: WHAT IS THE BORE AND STROKE OF THE 2011 TM MX300-2T?

A: The bore and stroke is 72mm by 72mm for a 294cc displacement. This is the bore and stroke of most 300cc dirt bikes. The TM MX300-2T has a 66.4mm bore and the same 72mm stroke.
Two maps: You get to choose between two ignition maps.


Q: HOW DID THE TWO-SWITCH MAP WORK?

A: The MX300-2T Cross has a two-map selector switch on the handlebars. The map differences weren’t as noticeable as on the TM four-strokes, but test riders still felt that Map 2 was better than Map 1. 

Q: WHAT ABOUT THE CLUTCH?

A: We loved the clutch, and we used it a lot. It was easy to pull, didn’t fade and self-adjusted when it got hot. The master cylinder is from Brembo, but the slave unit is designed and built by TM.

Q: WHAT ABOUT THE JETTING?

A: Straight out of the Italian crate, the TM MX300-2T Cross was lean on the bottom and rich on the top. We made low-end adjustments with the air screw, but for different altitudes and temperatures, a pilot jet change might be the best choice.

Here is what we ran in our bike for SoCal’s sea-level tracks:
   Mainjet: 165 
   Pilot jet: 50
   Needle: NOZE 
   Slide: 7.0
   Air screw: 1-1/2 turns
   Clip: Third from top
   Notes: For summer temperatures, we’d probably fiddle with the air screw and clip position to clean up the low-to-mid hesitation.

Q: HOW DOES THE TM MX300-2T HANDLE?

A: Over the years, the MXA wrecking has dreaded testing Italian bikes. We still have nightmares about the flex in the bolt-together frame of the VOR, major understeer of the Vertematti and slack angles of previous TMs. No more. We have to applaud the Italians, both at TM and Husqvarna, for abandoning their old understeer for a much more neutral frame geometry. Subject to setup and suspension settings, the MX300-2T Cross was a good-handling bike. It was very predictable at the entrance of turns and very stable in a straight line.
Italian razor: TM has produced a chassis that shares none of the irritating quirks that used to plague previous TMs. This is a stable platform bike that treads down the middle of the road when it comes to handling—not too quick and not too slow. 

Q: WHAT ABOUT THE BRAKES?

A: The TM MX300-2T has a fearsome brake combo. TM specs a massive 270mm front braking rotor. That is a big rotor—about 30mm larger than the standard Japanese front brake rotor. With a Brembo front-brake caliper (powered by a Nissin master cylinder), there is no such thing as going in too hot. The rear brake is also oversized, with a 245mm rotor (it gets the Nissin parts from a Yamaha). For riders who want to run their rear brake pedals low, we had to cut some threads off the master cylinder rod. (This is the same thing we do to Kawasaki brake rods.)

Q: WHAT ABOUT THE REAR SUSPENSION?

A: The Swedish-built Ohlins rear shock, unlike Kayaba and Showa shocks, is very sensitive to clicker changes. What you might accomplish on a CRF with four clicks, the Ohlins achieves in one. That means that overexuberance in solving a problem can contribute a whole new set of symptoms to the diagnosis. A savvy tuner will make small changes on the Ohlins. We carefully set the sag to 100mm, clicked the low-speed compression out until the shock responded positively, and lightened the rebound damping to allow the shock to reset itself for the next bump. All TMs imported to the USA come with Ohlins shocks, while many European countries get TMs with less high-tech Sachs shocks.

Gold-plated: In Europe, TM buyers get a Sachs shock, but the American version comes with a Swedish-made Ohlins.

Q: WHAT WAS OUR BEST SHOCK SETTING?

A: As a starting point, we recommend these settings:
   Spring rate: 5.0 kg/mm
   Race sag: 100mm
   Hi-compression: 1 turn out
   Lo-compression: 19 clicks out
   Rebound: 20 clicks out
   Notes: The rebound adjuster doesn’t use a screwdriver, but can be spun by hand.

Shiver: Marzocchi has come a long way, and it shows.
 
Q: WHAT ARE THE BEST FORK SETTINGS? 

A: We had some doubts when we first saw the Marzocchi forks, but our fears were for naught. The 50mm Marzocchi “Shiver 50” forks worked decently—no worse than many forks available on other brands. Fast riders will need stiffer springs. Luckily, Marzocchi has an American office (not far from MXA’s palatial headquarters) for parts and advice.

For hardcore racing, we recommend this fork setup on the 2011 TM MX300-2T:
   Spring rate: 0.45 kg/mm
   Oil height: 280mm
   Compression: 20 clicks out
   Rebound: 19 clicks out
   Fork leg height: 5mm up
   Notes: There is a tiny air-bleed valve hidden underneath a rubber plug on the fork cap; just press and go. Additionally, fork preload can be adjusted by turning the inner portion of the fork cap.
Q: WHAT DID WE HATE?

A: The hate list:
   (1) Height. As with most European bikes, the TM’s stance is a little taller than some MXA test riders like. Lower is better.
   (2) Triple clamps. The CNC-machined triple clamps don’t have rubber mounting for the handlebars. There was some vibration.
   (3) Grips. Domino grips aren’t on any MXA test riders’ top-ten lists.
   (4) Low-rpm bog. It didn’t happen often, but when it did, it was a big surprise. The power felt like it was there and then vanished. We kept our clutch hand on Defcon 4 at all times.
   (5) Bolts. Allen bolts fill with mud and have to be cleaned before they can be turned. The TM uses Allen bolts on the plastic parts, clutch cover, seat, engine cases and ignition cover. 
   (6) Black gas tank. Black gas tanks are cheaper to mold. That’s why manufacturers use them. Black gas tanks prevent a rider from seeing how much gas is in the tank when filling it—until his boots are damp.
   (7) Rear sprocket bolts. There are nine bolts on the rear sprocket. That seems a little excessive.
   (8) Shock preload ring. We hate KTM’s nylon preload-adjustment ring, so we weren’t thrilled to find it on the TM’s Ohlins shock.

Q: WHAT DID WE LIKE?

A: The like list:
   (1) Components. Unlike the typical bike, which comes from a variety of anonymous suppliers, TM uses Brembo, Takasago, Nissin, Ohlins, Marzocchi,BrakingReikon and HGS components. And there are lots of handmade CNC-machined parts on a TM. 
   (2) Brakes. The 270mm Brembo front brake is about as big and powerful as you would ever want on a 300 two-stroke. This thing could stop a charging rhino.
   (3) Hubs. TM’s hubs are works of art. They are billet-machined aluminum, highly polished, spool-style hubs that are laced to blue anodized Takasago Excel rims (with Michelin Starcross tires).
   (4) Ergonomics. The TM has a roomy feel to it, and the only thing the test riders complained about was that the bars felt too low.
   (5) Hydraulic clutch. Very sweet.
   (6) Shifting. Surprisingly good.
   (7) Displacement. The TM MX300-2T Cross is also available in a 249cc version.

Q: WHAT DO WE REALLY THINK?

A: Exotic motocross bikes are not for everyone. You need a strong personality to buck the trend and a modicum of mechanical skill to deal with problems (sans the ability to ask the guy next to you in the pits for advice). What is cool about the TM MX300-2T is that it is a brand-new, modern, high-tech two-stroke for riders who haven’t drunk the four-stroke Kool-Aid.

For more info on TM Motorcycles go to www.tmmotorcyclesusa.com

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