MXA’S 2012 TM MX250-2T MOTOCROSS TEST: THERE IS NO TWO-STROKE MOVEMENT; THIS BIKE DOESN’T EXIST; IGNORE THE MAN BEHIND THE SCREEN

March 22, 2012
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Q: WHO IS TM AND WHAT IS A BOUTIQUE BUILDER?

A: Italy-based TM is a boutique motorcycle builder. Boutique companies are small, intense and passionate manufacturers that build with their hearts instead of their pocket books. Sometimes, boutique builders grow up to become major manufacturers, but most often they stay small and build products to address the demands of their unique audiences.

TM started in 1977 when engine designer Claudio Flenghi and racer Francesco Battistelli quit their Italian motorcycle-industry jobs to create their own high-end, exotic bike for a niche market. TM has been successful enough to stay in business for 35 years.

Never a member of the “Big Five,” TM wasn’t bound by the constraints of mass marketing. TM could build what they wanted?and that gave them a reputation for building jewel-like machines with powerful and creative engines. In fact, Flenghi’s engine designs were so successful that they have become a major supplier to World Karting Championship teams.

Q: WHERE HAS TM BEEN FOR THE LAST FIVE YEARS?

A: Everywhere but the USA. In 2005, when the economy soured and money got tight, the market for exotic, expensive, one-off, Italian, two-stroke motocross bikes dried up. TM importer Pete Vetrano, of Motoman Distributing, decided to stop importing TMs and concentrate on other aspects of his business. Without Vetrano (a successful importer of several boutique brands) at the helm, TM bounced around from importer to importer until there wasn’t an American importer anymore.

In the fall of 2011, TM and Vetrano met by chance at a European motorcycle show. The rest is kismet. Vetrano agreed to take command of TM’s fate in the USA again, and the Italian stallions were again loaded in containers bound for America.
 

Modern iron: Technically the 2012 TM MX250 is a 2011 TM MX250 with BNG, but the Italian bike is a fully modern, up to date two-stroke, with more in-house trick parts than you can shake a stick at.

Q: IS TM A TWO-STROKE-ONLY COMPANY?

A: It is easy to get that idea because of TM’s karting heritage and lineup of 85cc, 125cc, 144cc, 250cc and 300cc two-strokes. But, TM also makes four-strokes with engines of their own design in 250cc, 450cc and 530cc displacements. The MXA wrecking crew has recently tested TM’s MX144 and MX300 two-strokes, along with their 250cc and 450cc four-strokes. Now we add the 2012 TM MX250-2T to the list (2T is Euro-speak for two-stroke).

Q: WHAT’S THE DIFFERENCE BETWEEN A 2011 AND A 2012 TM MX250-2T?

A: Since TM began importing bikes back into the USA late in the 2011 model year, what is the difference between a 2011 TM and a 2012 TM? Two things: BNG and the front fender. TM will be getting updated 2012 models, but mainly the TM MX125

Q: WHAT’S THE DIFFERENCE BETWEEN THE TM MX250-2T AND MX300-2T?

A: The bikes share almost every component, save for the center cases, cylinder, piston, jetting specs and porting dimensions.

Q: HOW FAST IS THE 2012 TM MX250-2T?

A: The TM MX250-2T does its best work in the middle of the powerband. The bike is responsive off the bottom with a bit of an old-school two-stroke feel, but does its best work in the midrange. It has a broad and steady pull until it falls off on top. It’s not an abrupt fall, but the power does sign off. Don’t think that means that the 250 has to be short-shifted, because most MXA test riders found that the MX250-2T’s midrange was broad and fruitful?especially if the rider worked his shifts to maximize the middle of the powerband.

Q: HOW DOES THE MX250’S POWER STACK UP AGAINST THE COMPETITION?

 
Italian fire: TM holds strongly to their two-stroke heritage. The TM MX250’s midrange powerplant was an effective race weapon after we added a tooth to the rear sprocket.

 
Auto upgrade: Euro models start with a Sachs shock, but all U.S.-imported TMs have Swedish-built Ohlins hardware.

 
Screeching halt: The Brembo caliper, 270mm rotor and Nissan master cylinder are a very potent combination.
 
50 cal: TM’s 50mm Marzocchi forks had the pogo syndrome at first. After some vigorous clicking, we were happy.

A: To find out, MXA set up a round-robin test session with three test riders switching back and forth between the TM MX250-2T, KTM 250SX and Yamaha YZ250. In these back-to-back comparisons, the TM’s overall power was super competitive with the YZ250. The YZ came on the pipe harder, but the TM’s transition was easier to manage. Once in the meat of the powerband, the TM and YZ could run nose to tail with each other. Neither the TM nor the Yamaha could match the KTM’s massive horsepower or willingness to pull hard and long to the rev limiter.

Q: HOW WAS THE GEARING?

A: Tall gearing is a European tradition. The MX250 came stock with 13/49 gearing (the TM EN250-2T enduro version had a lower 13/52 setup). With the stock gearing, there was a big gap between second and third gear. To compensate, most MXA test riders wound second out and then clutched across the gap. To make matters worse, some test riders complained that they were shifting down to first gear in tight turns.

The solution to both of these bugaboos was to install a larger rear sprocket to tighten up the gap, eliminate first as an option, make second gear the low-speed cog for tight turns, and get to third gear sooner. A 50-tooth rear sprocket made a night-and-day difference that suited the TM’s midrange power and internal gear ratios much better. It fixed the gap from second to third, and, contrary to common sense, testers shifted less often because they could stay in second in turns and quickly jump to third on the exit.

Q: WHAT ABOUT THE JETTING?

A: Italian two-strokes have a bad reputation when it comes to jetting, but those were old-school Dell’orto-equipped bikes from the early 1980s. Thankfully, the 2012 TM MX250-2T comes with a 38mm Keihin PWK carburetor.

Here is what we ran in our bike for SoCal’s sea-level tracks (EN250 jetting is in parentheses):
   Mainjet
: 185 (180)
   Pilot jet
: 50 (45)
   Needle:
NOZE
   Clip
: 3rd from top
   Air screw:
1-1/2 turns out
   Notes:
The MX250-2T ran perfectly in cool weather, but on warm days we had to adjust the air screw to lean out the mixture. In the dog days of summer, we might consider a smaller main.

Q: HOW DOES THE 2012 TM MX250-2T HANDLE?

A: The easy answer is that it handles identically to the 2011 TM MX250-2T, but that wouldn’t reveal much to TM-starved American consumers. In the good old days, the only thing that would make an Italian bike turn a tight corner was a brick wall. Italian bikes understeered and pushed. Thankfully, those days are gone. No more choppers from the Appian Way.

On the contrary, TM’s current chassis is on the aggressive side of neutral. Some of this can be attributed to the stinkbug stance and a momentary hiccup when passing through 25 degrees of lean on the entrance of turns. Thankfully, most of this is easily fixed with careful setup of the race sag and fork height.

The TM MX250-2T is an able-handling machine that, when set up properly, exhibits a touch of oversteer on the entrance and then goes neutral from the center out. Nice, but not exceptional.
 
Q: HOW GOOD ARE THE TM BRAKES?

A: They are 270mm worth of good. Japan specs their bikes with 240mm and 250mm front rotors. KTM goes upscale with a 260mm Braking front orb. Yikes, TM specs a 270mm rotor. TM’s brake combo is unique in that it uses Brembo calipers mated to Nissin master cylinders. The stopping power is worthy of a factory bike. The faster the test rider, the more he appreciated the brakes.

The only complaint was that the rear brake pedal could not be lowered enough to satisfy the old-school test riders. Not to be denied, they used a hacksaw to cut off a couple threads on the push rod to get the pedal below the footpeg height.

Q: WHAT ABOUT THE REAR SUSPENSION?

A: If you buy a TM in Europe, the base model comes with a German-built Sachs shock. Not in the good old USA. American importer Pete Vetrano didn’t want his customers to be searching for Sachs parts in Des Moines on a Saturday night, so he had TM install Swedish-built Ohlins shocks on every bike headed west across the Atlantic. Good move, because Ohlins makes high-quality components that every suspension shop is familiar with. Later this season TM will begin importing bikes with TM’s proprietary shock.

Here are a few notes about the easiest way to get the shock dialed in on the MX250-2T:

(1) Front/rear balance . The forks play a big role in how well the shock works, so get the front end in the ballpark before fine-tuning the shock. The rear end is especially important for two-strokes, so adjust it last.

(2) Stinkbug . The bike’s attitude leans to the stinkbug side of the scale. Most test riders compensated for this by running 105mm of sag (instead of 100mm). Additionally, they lowered the forks 2mm to bring the chassis closer to level.

(3) Clicks.
No shock on the planet is as adjustable as an Ohlins. MXA test riders could feel the difference between single clicks on compression or rebound, so when making adjustments don’t get too carried away with spinning the clickers.

Q: WHAT WERE OUR BEST SHOCK SETTINGS?

A: Here is what we ran in our bike for hardcore racing (stock settings are in parentheses):
   Spring rate
: 5.2 kg/mm
   Race sag
: 105mm (100mm)
   Hi-compression
: 1 turn out (1-1/2 turns out)
   Lo-compression
: 19 clicks out (13 clicks out)
   Rebound
: 15 clicks out (22 clicks out)
   Notes:
The rebound adjuster is a ring that can simply be clicked by hand.

Q: WHAT WERE OUR BEST FORK SETTINGS?

A: Through the years, Marzocchi’s forks have been somewhat hit-and-miss, but with the introduction of the Shiver model, they have become a player in the suspension game. You gotta love the Shiver’s massive, 50mm fork legs and black anodized fork tubes. For racers who like an active front end, the stock TM setting is in the ballpark. The forks feel very fluid and supple in the initial part of the stroke. They maintain their plushness through the midstroke, but about the time when they should be ramping up on the compression damping, they stay fluid. Most test riders, even the small ones, wanted more compression at the end of the stroke and increased resistance to bottoming. The quick and easy fix was to raise the fork-oil level in 5cc increments.

For hardcore racing, we recommend this fork setup on the 2012 TM MX250-2T:
   Spring rate
: 0.45 kg/mm
   Oil height:
300cc
   Compression
: 10 clicks out (20 clicks out)
   Rebound
: 15 clicks out (20 clicks out)
   Fork-leg height:
3mm up
   Notes:
Fast or heavy riders will have to increase the spring rate, while everyone else can just add 5cc of fork oil to each leg to ramp up the compression earlier. One note: the air-bleed valve is 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) Radiator cap. We got a defective cap that fell off twice. Part of the issue is that the radiator spout sits well above the radiator shroud and is exposed to danger. We got lucky and found the errant cap?once. Fortunately, we had a CV4 KTM cap that fit perfectly.

(2) Sprocket bolts . Does it really take nine bolts to secure a rear sprocket? TM makes a good engine, but come on, guys, it’s not that powerful.

(3) Gas cap. Be careful about keeping the seal in the gas cap bedded and the cap threaded properly, because we experienced some spillage.

(4) Bar mounts. The bar mounts and top clamp are one solid piece. We don’t like the beefy look and think it transmits more vibration?whether it is actual or just perceived.

(5) Allen heads. The Italians seem to have an affinity for Allen bolts…we don’t get it. They get packed with mud and make the bike difficult to work on at the track.

(6) Seat . Some tester put this on his “like” list, but most testers wanted a lower, softer saddle.

(7) Rear brake pedal.
It sits high and cannot be lowered without some mechanical help.

Q: WHAT DID WE LIKE?

A: The like list:

(1) Parts . If you have never seen a TM in person, it will definitely get your attention. It is trick, as you would expect from a boutique builder.

(2) Front brake . It would be considered oversized for any of the “Big Five,” but TM calls it standard. It gets the bike to stop, no problem.

(3) Map switches. There wasn’t a huge difference between the two maps, but the handlebar-mounted switch was fun to play with.

(4) Shifting.
It’s important on two-strokes, and, luckily, shifting was very accurate on the TM MX250-2T.

(5) Hydraulic clutch . Very sweet.

(6) Big bore. The TM MX250-2T is also available in a 294cc version.


Blip the lip: Like most 250 two-strokes, the TM bounded lightly over obstacles and didn’t mind if the rider chopped the throttle on the jump face.

Q: WHAT DO WE REALLY THINK?

A: TM has a lot of pride in their two-stroke heritage?and the MX250-2T oozes it. The MX250-2T is a special bike, and it shows in its scary, $8310 price tag. For the money, you get a bike that is competitive, unique and not found on every street corner (maybe in Pesaro, but not in Des Moines). It may not be the most practical race bike ever, but it is passionate. For more info on TM Motorcycles, go to www.tmmotorcyclesusa.com.

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