2006 Xtreme Pro Stock 125 Bike Test

April 4, 2007
JC Hilderbrand
JC Hilderbrand
Off-Road Editor|Articles|Articles RSS|Blog |Blog Posts |Blog RSS

Hilde is holding down the fort at MotoUSA's Southern Oregon HQ. With world-class dirt bike and ATV trails just minutes away, the hardest part is getting him to focus on the keyboard. Two wheels or four, it doesn't matter to our Off-Road Editor so long as it goes like hell in the dirt.

Highlights of the 2006 Xtreme Pro Stock 125 are its engine  4-speed tranny  and its new aluminum frame.
The Xtreme Motor Company, the people that helped fuel the fire for the mini moto craze with its pit pro bikes, sent us its 2006 Xtreme Pro Stock 125 to use and abuse.

The successful launch of the Xtreme Motorsports “Original” Cooper Replica Pit Pro CR107 in 2004 helped kick off the mass appearance of affordable race minis. Since then the Arkansas-based company has been refining and expanding its line of race-ready equipment and branching into street markets as well. Since my dirty mind isn’t particularly interested in a small-bore cruiser or scooter, we borrowed the new 2006 Pro Stock 125 to toss up some roost.

Immediately after taking delivery of the blue, SOHC, 124cc Thumper, all of our would-be roost turned to mud and our mini testing program came to a rain-soaked halt. With the weather recently back in our favor, we headed out to finish this eval at our favorite track that was prepped and dragged especially for us.

From the beginning Xtreme has been associated with Guy Cooper. Imitation is the sincerest form of flattery, so we thought we’d make like old Air Time and be tossing mini whips in no time. Not quite. It was fast apparent that we wouldn’t be freestyling this little guy. The Pro Stock certainly feels like a stock bike in the suspension category, or at least it does in comparison to some of the other minis we’ve ridden. We’ve had the pleasure of spinning laps aboard some bad-ass aftermarket springs and some factory specs in the Monster/BBR 115 from last summer. Unfortunately, the Xtreme isn’t on par with either. Even our lightest tester found both ends too soft for his 135, jump-happy pounds. You can imagine the consequences for larger riders.

Under different riding conditions  the Xtreme would have kicked up a nice roost  but JC had to settle for slinging a little mud.
Oregon winters turn the soil to muck, but at the first sight of sunshine JC was determined to put the Xtreme Pro Stock 125 to the test.

This doesn’t mean the bike doesn’t do some things well; it’s just that jumping just isn’t one of them. As you probably assumed, the soft 33mm fork and rear shock do a good job on small rubble, but the boundaries are quickly stretched with the 6 inches of front travel and 5 inches out back reaching their limits in clanking fashion. Perhaps the biggest letdown on the suspension was a lack of adjustability. Neither fork nor shock offer any room for tailoring compression or rebound damping. It’s possible to adjust preload on the shock, but that is as far as it goes for fine tuning.

Thankfully, as quickly as we identified the suspension as a weakness, the motor, 4-speed manual transmission and new aluminum frame emerged as the highlights. To start with, the motor feels comparable to other 125cc machines. It doesn’t rev as quickly as some high-strung customs, but it makes up for it in reliability. We never had any problems with the engine despite running it through multiple track days with riders ranging from beginner to pro and up to 190 lbs.

Xtreme’s 125cc motor is probably the most competitive feature on the bike. After we dropped the needle one position to clean up the 20mm carburetor, it pulled strong across the power range without glitch. We didn’t ride in temps above the low-70s, but oil and air cooling was sufficient to keep the bike from overheating. Our heaviest testers could just get it to pull third gear effectively on fast straights, but fourth was out of the question for motocross applications. Our lighter, and faster, guys were able to use the gearbox more extensively.

Testing on an arenacross track was just one of the ways we escaped soggy conditions.
Testing on an arenacross track was just one of the ways we escaped soggy conditions. Jumping the Xtreme must be done with care. Even on a track with groomed landings, the soft suspension is still overwhelmed.

Shifting the four-up pattern is precise and easy. Our clutch was a little out of adjustment to begin with, but once it was at the proper tension things worked smoothly. The clutch does fade fairly quickly, which leaves the rider banging gears late in a moto, but it returns quickly and adjusting the cable tension religiously kept us in play-mode all day.

An all-new aluminum chassis and swingarm help keep weight down to 133 pounds, tank empty. It’s still not the lightest-feeling bike while loading your pickup, but on the track it feels relatively nimble. The 12-inch rear tire and 14-inch front offer ample traction with Xtreme’s own “Original” custom knobby pattern. The bike’s actually a pretty big layout, with the seat height at 30 inches and wheelbase stretched to 43. There’s one problem, however, that keeps riders from fully enjoying the 110-sized cockpit: extra-soft seat foam. Riders get sucked in deeper than an overstuffed Barcalounger, which makes moving around a chore. Luckily, most of the movement that happens on minis is standing up and sitting down, which isn’t really hampered by the spongy seat. This foam would be a catastrophe on a big bike, though.

Upon first straddling the Pro Stock, MotoUSA’s mini guru, Brian Chamberlain, noted, “It doesn’t have a whole lot of seat foam. Actually I guess it does, but it’s made of marshmallows.”

The 198mm wave-style rotors had a good bite despite all the caked-on mud.
The front wheel’s 198mm hydraulic disc with wave-style rotors had a good bite despite all the caked-on mud.

If we wanted to ride the world’s largest s’more, a gooey center would be just dandy. As it was, we got tired of coming away with bruised butt cheeks from bouncing off the subframe rails. The seat wasn’t always this soft. Foam density was normal during our first ride but subsequently became softer and softer with each outing. It only took three rides to reach Stay Puff status, but it now seems to have reached peak squishiness, thankfully not squishing further.

The seat epitomizes the Xtreme’s biggest problem – a poor user interface. Every component that connects the rider to the bike needs some improvement. Because they are literally what a rider holds onto, it’s easy to get a more negative impression than this bike really deserves. From top-down, the hand grips are some of the least comfortable we’ve ever used. Our bike was fresh out of the crate, but the grips reminded us of an old tennis ball that’s been lost under the hedge for a couple years; what should be firm-yet-pliable is instead hard and brittle.

Further south is the aforementioned seat which is coupled with rudimentary and wimpy suspension. The last missing piece of the Pro Stock puzzle are the footpegs. They’re mounted through the frame, which is a blessing. We’re sure the cases would be destroyed if they were bolted directly to the motor like some other budget minis. The pegs are fairly wide and stout, but almost all of our testers used the same term to describe them: droopy. They fall away from the bike which was generally an unwelcome feature. Only one of our testers liked the pegs and thought they allowed for him to get his feet on and off steel teeth with ease, especially in full-size boots.

Get it JC! What better way to truly test the suspension than with some onboard air-time.
In order to give a fair assessment of the mini, JC goes to extremes to test the 2006 Xtreme Pro Stock 125.

Riding the Pro Stock 125 in today’s mini world is kind of like buying a kick-ass laptop and using DOS. Sure, it works and you can get the task accomplished, but ultimately it’s being unnecessarily handicapped. The potential is right at your fingertips but unless you take the initiative to install Windows XP, the user interface will always be a bit slower and a serious pain in the ass (pun intended).

The good thing about all this is that each and every complaint is easily fixed with a few aftermarket accessories. Xtreme buyers should be able to upgrade to a set of burly pegs, replacement seat foam and tacky grips for in the neighborhood of $200. Even with the extra expense, the Xtreme still rings in for less than many pre-fabbed pit bikes. Getting into the suspension issues will take a considerable amount of dough, but these quick fixes will help minimize the suspension shortcomings. If you want to get extra serious about your race results, go ahead and order the necessary components to upgrade your suspension. Even though it’s a little weak, we bet you’ll be flogging what’s there until the new stuff shows up. This bike is still plenty of fun.

If you really want to race hard and often, Xtreme offers the Original Pit Pro “CR” Stage III. This Cooper Replica is a more advanced package, but the differences between the two aren’t in the areas that really need improvement. A disc brake in back, matching 12-inch tires and a slightly smaller stature and claimed weight are the main alterations, which do nothing to solve the suspension and seat woes. Since we haven’t tested the Stage III, we’ll just stick to what we know, and the Pro Stock offers plenty for the majority of weekend riders.

JC turns a wrench while the cameraman gives us a good look at the 33mm oil-damped telescopic fork.
Adjusting the handlebars was a real pain. Attention to details like this probably weren’t overlooked, just ignored to help keep the retail price low.

“It could be competitive in local pit bike races but nothing more,” says pro rider Mike Horban. “I guess for 1900 bucks it’s pretty good. It just needs a shock and some fork work.”

A perfect example of how this bike does a good job of offering performance while remaining an affordable $1899 MSRP is in the braking system. A 198mm wave-style rotor on front complements the sturdy handling. The hydraulic system never faded or had any problems whatsoever. We had a Pitster Pro X2R on hand, and the Xtreme front binder had much better bite. Out back is a drum brake which is completely adequate for the speeds this bike is capable of. Some of our testers felt the drum rear, while not as cool as a matching wavy rotor, was a highlight simply because it helps keep costs low, is easy to adjust and is less susceptible to damage.

The only mechanical problem we had with the Pro Stock was a failed wheel bearing in the rear wheel. Once we pulled it apart we discovered that another was on the verge of uselessness. Having to replace 2-of-3 bearings in the rear was discouraging after only two rides, but once they were replaced the problem didn’t repeat itself.

“For the price, the bike is a good deal,” sums Martin. “It has a fast motor and really good handling.”

As with any bike, you’ve got to take the bad with the good. Considering what this bike is manufactured to do, it doesn’t have anything really bad about it. Once we readjusted our race attitude, the bike comes across in a much better light. As Ian said, the motor is fast and reliable, handling is awesome and the revised 4-speed transmission handles a ton of abuse. Cap it off with a great braking package and the Pro Stock 125 delivers exactly what’s promised: a terrific foundation to build a race winner.

The Xtreme isn t the lightest bike on the scales  but it feels maneuverable on the track.
The Xtreme isn’t the lightest bike on the scales, but it feels maneuverable on the track.

Xtreme Pro Stock 125 Specs:

Engine Type: Air/Oil Cooled SOHC single-cylinder 4-stroke
Displacement: 124cc
Bore x Stroke: 52.4 mm x 57.5 mm
Compression Ratio: 10.0:1
Carburetion: 20mm Slide Piston
Horsepower: 8.2 ps @ 8500 rpm (claimed)
Torque: 7.2 N.m @ 6500 rpm (claimed)
Transmission: 4-speed manual SCR Team Cooper Special
Shift Pattern: 4 up
Ignition: Electronic C.D.I
Start System: Kick
Fuel Capacity: 0.8 Gallons
Oil Capacity: 1 quart 10W-40
Seat Height: 30.0 inches
Wheelbase: 43.0 inches
Overall Length: 62.5 inches
Overall Width @ Handlebars: 29 inches
Overall Width @ Pegs: 20 inches

The 2006 Xtreme Pro Stock 125 at China Gulch.
With the fervor surrounding the mini market, the Xtreme Pro Stock 125 needs a few aftermarket upgrades but has the potential to be a stalwart starting racing mini.

Ground Clearance: 12.0 inches
┬áTire Size: 2.75 x 14 (front); 2.75 x 12 (rear); “ORIGINAL” Custom Xtreme Knobby Pattern
Front Brake: 198mm Hydraulic disc with Wave Rotor
Rear Brake: Drum
Front Suspension: 33 mm Oil Damped Telescopic forks
Rear Suspension: Hi-performance Mono Shock with New Tapered Aluminum Swingarm
Suspension Travel: 5.0″ front / 6.0″ rear
Dry Weight: 133 (tank empty)
Available Colors: Blue and Orange
MSRP: $1899

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