REAL TESTS! 2010 MXA RACE TEST OF THE HUSQVARNA TC250:

July 3, 2010
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Q: FIRST AND FOREMOST, IS THE 2010 TC250 BETTER THAN THE 2009 TC250?

A: We’re going to say yes, because Husqvarna did not import the 2009 TC250 to the United States. The last Husqvarna 250cc four-stroke that MXA tested was back in 2005. It was an electric-start, 237-pound, undersprung, slow bike that we said was “a blast to ride, but not all that much fun to race.”

Q: WHAT CHANGES DID HUSQVARNA MAKE TO THE TC250 FOR 2010?

A: The MXA wrecking crew got a sneak peek at the 2010 Husqvarna TC250 way back in February 2009 in the Canary Islands. We were impressed by the handling characteristics of the TC250, but we noted that the powerband wasn’t anything to write home about.

The Italian company, owned by BMW, spent the last eight months improving on the prototype that we rode on the Spanish islands. Their goal was to produce an extremely light motorcycle with improved reliability, performance and handling. Here are the list of changes on the 2010 Husqvarna TC250:

(1) Engine. Husqvarna deserves immense credit for building the smallest and lightest engine in the 250 four-stroke class. Thanks to a Formula One engineer who focused on the lower end, Husqvarna was able to shrink the powerplant down to a svelte 48 pounds. That is ten pounds lighter than any other 250 engine.

(2) Suspension. After years of using Marzocchi Shiver forks, Husqvarna made the switch to 48mm Kayaba forks. To work in conjunction with the Kayaba forks, Husqvarna designed new triple clamps. Not new, but certainly worth noting, is that Husqvarna relies on the Austrian-built Sachs shock. This system has come standard on the TC250 for many years.

(3) Plastic. Husqvarna continues to be a trendsetter in their plastic design. For 2010, they developed stronger, more flexible plastics. There are also new inmold graphics embedded into the radiator wings and side panels.

(4) Frame. Husqvarna and KTM are the last two proponents of chromoly frames. In the past, the TC250 shared its frame with the TC450. This was not a recipe for a lightweight chassis. Thanks to the all-new, compact engine design, the 2010 TC250 now uses the CR125 two-stroke frame.

(5) Swingarm. The swingarm has been shortened by 15mm to improve traction and handling.

(6) Rear brake rotor. The 2010 TC250 uses a cauliflower-shaped, 240mm, Braking rear rotor. It is self-cleaning and dissipates heat.

(7) Cooling. The TC250 has new radiator connectors and coolant hoses, as well as a high-performance water pump for improved cooling system efficiency.

(8) Wheels. The new front and rear wheel hubs are lighter and stronger (the axles have been improved as well).

The swan: Husqvarna’s ugly duckling days are behind them. The cutting edge styling of the Italian bike is now mainstream.

Q: HOW FAST IS THE 2010 HUSQVARNA TC250?

A: Although the MXA wrecking crew is enamored with Husqvarna’s amazingly compact engine design, we had to take the rose-colored glasses off after racing the 2010 TC250. Why? In short, the TC250 is slow?in every sense of the word. MXA test riders complained in unison that the Husqvarna engine lacked the hit, snap and punch that they yearned for.

As a rule of thumb, 250cc four-stroke engines have at least one rpm range where they shine. For example, the 2010 KTM 250SXF is impressive at high rpm, the 2010 Yamaha YZ250F has brilliant low-end throttle response, and the 2010 Honda CRF250 does its best work in the midrange. Thus, we expected the 2010 Husqvarna TC250 engine to have its moment. It did, but it was so low on the rpm band that it wasn’t usable. Overall the low-end was anemic, midrange lackadaisical and top-end sickly.

Q: WHAT IS THE BEST WAY TO USE THE TC250’S POWERBAND?

A: Getting the Husqvarna to move forward on the track requires a two-stroke approach. What do we mean? In order to be successful, we had to be willing to abuse the clutch, dance on the edge of valve float and never shut off (even when the clutch was pulled in). Keeping the engine shrieking masked the TC250’s laziness exiting turns. Flubbing a corner was the kiss of death. Test riders who rode with abandon could be rewarded, but the potential for mistakes with this riding style meant that even the slightest flub would lead to the pack passing by and fading into the distance.


Prize: The TC250 engine is light, small, compact and slow.

Q: HOW DOES THE 2010 HUSQVARNA TC250 COMPARE TO ITS COMPETITION ON THE DYNO?

A: We’ve tested bikes in the past that felt slow on the track, but produced excellent horsepower figures on the dyno (and vice versa). Unfortunately, the 2010 Husqvarna TC250 doesn’t fall into either category. It’s slow on the track, and it’s slow on the dyno.

Maximum horsepower is 34.26 at 10,800 rpm with 18.89 foot-pounds of torque. The 2010 YZ250F reached 35.88 horsepower at 11,500 rpm with 19.19 foot-pounds of torque. The 2010 CRF250 produced 36.37 horsepower at 10,400 rpm with 19.18 foot-pounds of torque. The KTM 250SXF (the most impressive of the four bikes on the dyno) pumped out 36.90 horsepower at 12,200 rpm with 19.33 foot-pounds of torque.

An overlay of the four bikes’ dyno charts reveals that the TC250 tops the field from 5500 rpm to 6200 rpm (a place on the rpm curve that is rarely used on a 250cc four-stroke). From 6300 rpm through 13,000 rpm, the TC250 is the least productive bike. The engine tapers off quickly after it reaches peak horsepower at 10,800 rpm (when nearly every other bike is still climbing up the horsepower scale).

Q: WHAT WOULD BENEFIT THE 2010 HUSQVARNA TC250 ENGINE THE MOST?

A: There are several problem areas that the MXA wrecking crew thinks can be addressed by the aftermarket this year (and by Husqvarna engineers in the future).

(1) Starting. We haven’t encountered such a temperamental bike in a decade. It doesn’t want to start, and the situation isn’t helped by a kick-start lever that barely spins the engine over (and when you do get a healthy rotation going, the kick-starter gets stuck in the footpeg…and bends with use). Through trial-and-error, we learned several techniques for starting the Husqvarna:

Cold engine. When cold, pull the choke out, keep away from the throttle, and kick with as tall and steady a stroke as possible. We’d like Husqvarna to change the gear ratio on the idler gear to get the engine to turn over more times per kick.

Hot engine. Starting the TC250 when hot requires pulling out the hot start button (inconveniently located on the carburetor), finding top-dead-center, nudging the kick-start slightly past compression, and then kicking slowly. Patience is a virtue, especially when starting the red hot TC250 engine.

Foolproof method. Sit bolt upright in the saddle and have someone push you down a hill.

(2) Exhaust. MXA is currently testing a prototype Pro Circuit TC250 pipe. The stock TC250 exhaust isn’t getting the job done when it comes to producing usable ponies on the track or dyno. On the plus side of the TC250 chart, the stock TC250 exhaust is very quiet. At 93.1 dB, the titanium pipe easily passes the current AMA/FIM 94 dB sound limits.

(3) Forks. We were happy to see that Husqvarna switched to Kayaba AOSS forks for 2010. We’ve had good luck in the past with Kayaba, and there is a wealth of tuning information available for the AOSS units. The stock setup is way too soft. We swapped out the stock 0.43 kg/mm springs for heavier 0.45 kg/mm springs immediately.

Q: HOW IS THE JETTING?

A: Slightly rich would be the best way to describe the stock jetting. The first step is to adjust the accelerator pump so that the set screw is backed off 1-1/2 turns from contact. MXA‘s recommended jetting is as follows (stock settings are in parenthesis):
   Main: 180 (190 stock)
   Pilot: 40
   Needle: OBDVR
   Clip position: 3rd from top (5th from top)
   Fuel screw: 2 turns out (1-1/2 turns out)

 
Q: HOW WELL DO THE NEW KAYABA FORKS WORK?

A: Perhaps the most shocking news of the 2010 season was Husqvarna’s switch from Marzocchi forks to Kayaba (2007 YZ250F forks to be exact). The TC250’s Kayaba forks are a good package. The only downside is that the spring rates are too soft for many riders. If you weigh under 150 pounds or are a Novice or lower-level rider, then the forks will be sufficient. Anyone not fitting into this bracket (in weight, speed or intent) will need to jump up a spring rate. Once stiffer springs were in place, MXA test riders were happy with the performance of the Kayaba forks.

Q: WHAT ARE MXA’S RECOMMENDED HUSQVARNA TC250 FORK SETTINGS?
 
A: Here is what the MXA wrecking crew ran in its 2010 Husqvarna TC250. Stock settings are in parenthesis:
   Spring rate: 0.45 kg/mm (0.43 kg/mm)
   Oil height: 290cc
   Compression: 14 clicks out (9 clicks out)
   Rebound: 16 clicks out (13 clicks out)
   Fork leg height: 5mm up


Sachs shock: The shock is amazingly good.

Q: WHAT DO WE THINK ABOUT THE SACHS SHOCK?

A: The Sachs shock is very unique, and you might assume that the MXA wrecking crew would approach it with some trepidation. Not true. We have had nothing but good luck with Sachs shocks in the past. The shock offers many different options, and coupled with the proper spring rate and damping, the shock works very well. The Sachs shock has a unique feel compared to the Showa, Kayaba and WP shocks that we’ve tested. The Sachs has a very springy feel to it, but that’s not necessarily a bad thing. On whooped-out straights and through braking bumps, the Sachs shock soaked up the chatter and didn’t transfer it through the chassis. If it weren’t for the soft fork springs, test riders would immediately find comfort in holding the throttle on through the roughest sections of many tracks.

Q: WHAT IS MXA’S RECOMMENDED HUSQVARNA TC250 SHOCK SETTING?

A: Here is what the MXA wrecking crew ran in its 2010 Husqvarna TC250. Stock settings are in parenthesis:
   Spring rate: 5.4 kg/mm
   Race sag: 100mm
   Hi-compression: 11 clicks out (10 clicks out)
   Lo-compression: 16 clicks out (15 clicks out)
   Rebound: 16 clicks out (18 clicks out)
   Notes: We recommend running between 100 and 105mm of sag to maximize the shock’s potential.

Q: IS THE CHROMOLY STEEL FRAME A PLUS OR A MINUS?

A: Plus. Steel frames are not dead. KTM and Husqvarna have good reasons for sticking with chromoly steel.

(1) Weight. When used properly, a steel frame can be lighter than an aluminum frame.

 
(2) Flex. Steel frames are livelier and more flexible. With every aluminum frame manufacturer trying to feed flex back into their Delta-Box frames, it seems that the virtues of rigidity were overstated.
 
(3) Modification. A steel frame can be repaired, strengthened or gusseted with welding-shop simplicity.
 
(4) Access. If you need to work on the carburetor on a bike with a Delta-Box frame, you are out of luck. Husqvarna’s steel frame doesn’t just make the carb accessible, but it can be worked on without taking it off the TC250.
 
(5) R&D. With a steel frame, factory engineers can easily make geometry changes without having to wait for cast or forged parts to be made. This allows for more options during the prototype cycle.

Q: HOW DOES THE 2010 HUSQVARNA TC250 HANDLE?

A: MXA test riders liked the way the Husky handled. It didn’t do anything weird through corners, nor did it suffer from head shake. We could hit inside lines with ease and rail outside lines without dealing with understeer. It should be noted, however, that conven-tional wisdom points to the fact that slow bikes always handle well because they aren’t subject to the G-forces caused by rapid acceleration.

Of all the areas on a motocross track, the 2010 TC250 feels most comfortable in the air. The Husky is light and flickable, thanks to the narrow-feeling chassis and the lightweight engine.

Q: WHAT DID WE HATE?

A: The hate list:

(1) Powerband. Sometimes good things come in small packages. Sometimes not. The Husky engine is light, compact and slow. As with most “first-year” designs, the Husqvarna has nowhere to go but up in the future.

(2) Starting. Husqvarna needs to address their starting issues. After a dozen kicks, we started getting melancholy thoughts of the old electric-starting 2005 TC250. The five-year-old bike was heavy, but at least it started.

(3) Hydraulic clutch. Typically, the MXA wrecking crew is in love with hydraulic clutches, but the Brembo unit on the TC250 faded when it got hot. It would actually come and go in the middle of a moto  (and following heavy acceleration several test riders complained that the clutch was unresponsive). We bled the system and eventually replaced the slave unit, but the problem never went away.

(4) Side panels. Wait a second, there aren’t any side panels on the Husqvarna TC250.

Q: WHAT DID WE LIKE?

A: The like list:

(1) Suspension. A quick spring rate change makes a huge difference on the Kayaba forks, but even in stock trim the suspension works well. We especially liked the Sachs shock.

(2) Sound. The TC250 has a quiet exhaust pipe. It may hinder performance, but it measured 93.1 dB in our test. Did we also mention that it’s titanium?

(3) Handling. The TC250 settles into corners and doesn’t do anything weird.

(4) Front brake. The Brembo unit is powerful and progressive. It is superior to any other front brake in its class, except for KTM (which also has a Brembo brake system).

(5) Tires. The Pirelli MT32 tires worked quite well in varied terrain, especially in soft-to-intermediate dirt.

Q: WHAT DO WE REALLY THINK?

A: The 2010 Husqvarna TC250 is step one. It has an incredibly small engine, pleasant chassis, strong brakes and workable suspension. Step two will be to get more power from that revolutionary engine.

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