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2011 Yamaha YZ125 First Ride

Wednesday, December 29, 2010
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2011 Yamaha YZ125 First Ride Video
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Watch the small-bore YZ in action in the 2011 Yamaha YZ125 First Ride Video.
Four-strokes continue to develop on the forefront of dirt bike technology, and it’s safe to say, generally speaking, that the buying public and media have been sucked into the thunderous vortex. That isn’t to imply that there’s no interest in two-strokes, nor that they are competitive. There are plenty of holdouts and die-hard premix riders (you all remind me every time we post a new four-stroke test). But, the changing of the times is undeniable and in the last decade we’ve all been swept up to a certain extent. The point is that when we do get to ride two-strokes like Yamaha’s 2011 YZ125, we get to reexamine an old concept with fresh eyes – and what a treat it is.

Yamaha is the only Japanese manufacturer still importing two-strokes to America, and after a day of riding them at Milestone MX we’re sure glad it makes the effort. Yamaha ships these bikes all over the world and rather than making different models for different countries, the Tuning Fork brand has elected to standardize the bike for easier global distribution. For 2011 the YZ125 receives minor updates which make it able to pass European standards. Passing a 96 dB sound limit is the concern and the 125 gets a revised silencer in order to meet code. Core diameter increases from 27 to 30mm and the silencer is 75mm longer overall. The new dimensions allow it to be packed with nearly 72% more glass wool. The 38mm Mikuni carburetor gets some internal tweaks to make the bike run properly with the new exhaust by allowing more fuel. A needle change equals a half-clip richer and the main jet jumps to a 430 (from 410). Our day at Milestone revealed a strong and clean-running 124cc machine. The piston squishes premix into a 54 x 54.5mm bore and stroke which delivers power through the six-speed transmission.

2011 Yamaha YZ125 First Ride
2011 Yamaha YZ125 First Ride
The YZ gets a new exhaust silencer which helps
it stay at 96 decibels. All of our riders found that
the bike has plenty of power to get over jumps.
“The YZ has a great overall powerband for a 125,” says intermediate tester, Nick Thiel. “It pulls itself well through all the corners and has good throttle response as long as you stay on top of gear selection - which is normal for any small-bore two-stroke. I had no problem getting over any of the jumps and even found myself over-jumping a few due to how much extra corner speed I would carry. This being said, I would say it is still under-powered compared to any of the 250F motorcycles. But if you’re looking for a great motorcycle to have fun on or looking for a great transitional bike from the 85 to the 250F, this bike is awesome.”

Riding the 125 is an act of precision. It’s pretty easy to keep the right wrist tipped back, but the little YZ requires an active left hand and foot to keep it driving forward. The clutch and tranny work flawlessly and require very little pull. We hammered through the gears without the clutch and the blue machine never complained, just changed cogs and went on its zippy way. It doesn’t take long to get back in the swing of riding these tiddlers and by the second session lines were coming together and by the end of the day even our slower rider was clearing everything on the track. Even though the YZ takes a lot of effort to ride, it’s still easier to put in longer motos than any other big bike. Manhandling a 125 is nothing like a 250F, and even when it’s on the pipe the bike never yanks it ProTaper handlebars out of the rider’s grip. Being aggressive at the controls is a necessity and the reason it’s so much fun to ride.

“I rode the bike hard for 30 minutes and had very little clutch fade, which was great,” comments Thiel. “The transmission worked flawlessly and I had no complaints. After riding the bike for a while I noticed the gearing was a bit short but I think this helps with keeping the bike on the pipe thus helping to alleviate potential clutch fade.”

Keeping the motor singing is a thrill in its own right, but the thrills just get bigger when it’s time to pitch the 125 into a corner. With a claimed curb weight of only 208 pounds, the YZ is feather-light. The 48mm Kayaba fork and shock were both a little soft for our testers, but they still handled everything with ease. Big jump landings were the roughest, but the Kayabas were especially good on braking bumps. The lightweight machine flies into corners with control and a lack of engine braking helps it skim across corner entry. Once in the turn, the YZ is extremely predictable and is more than willing to find any rut your eyes can identify. Also, because its power isn’t explosive, tracking through flat turns is easy as well.

2011 Yamaha YZ125 First Ride
2011 Yamaha YZ125 First Ride
Handling on the YZ125 is a strong point. Our testers had the confidence to throw it around and take any line through the turns at Milestone MX.
“The handling was the best part about riding this bike,” Thiel says. “The line choices are endless. Anywhere you want to go whether it is inside, outside or down the middle of a flat corner, the bike works great. It has amazing stability through the rough sections and also felt light and flickable in all the corners and on the face of jumps.”

Yamaha’s aluminum chassis is easy to grip and takes little input to throw around. The rider triangle is confortable despite our larger testers who appreciate the lofty 39.3-inch seat height.

“I have always meshed really well with the ergonomics of Yamahas,” continues the 6’1” Thiel, “and the 125 is no exception. It has a nice midsection with a nice open layout. It may be a bit cramped for anyone taller than me, but I had no complaints.”

Even though Yamaha hasn’t dumped a lot of R&D into the YZ125, at least it’s still available in US dealerships. As an important stepping stone from youth machines to full-size dirt bikes, the YZ is a smart move for someone looking to ease into the world of high-powered motocrossers. It’s also a smart move for anyone wanting a ride that’s easy on their bank account. Maintaining a 125 is far less expensive than a 250F and the MSRP of $6250 is significantly lower as well. There wasn’t a single journalist or test rider who wouldn’t mind having the YZ in their garage permanently, regardless of skill level. Because of its impeccable handing, light weight and wide-open-all-the-time engine, this is a top choice for any rider whose top priority is having fun.

“After riding the YZ it made me remember how much fun screaming around the track on a 125 still is,” sums up Thiel. “Being close to $1000 cheaper than a 250F, this bike is the absolute most fun you can have for the money.”

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Technical Specifications
2011 Yamaha YZ125 First Ride
2011 Yamaha YZ125
Engine: 124cc, liquid-cooled, 2-stroke, reed-valve inducted
Bore x Stroke: 54.0 x 54.5mm
Fueling: Mikuni TMX 38
Transmission: Six-speed
Front Suspension: Speed-sensitive 48mm Kayaba fork; fully adjustable, 11.8 in. travel
Rear Suspension: Fully adjustable Kayaba shock; 12.4 in. travel
Front Brake: Hydraulic single 250mm disc
Rear Brake: Hydraulic single 245mm disc
Seat Height: 39.3 in.
Wheelbase: 56.8 in.
Ground Clearance: 15.2 in.
Fuel Capacity: 2.1 gal.
Curb Weight: 208 lbs (claimed)
Warranty: 30 Day (Limited Factory Warranty)

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Kyle818 -Kmanracer.  January 10, 2011 02:46 PM
@Rancher, do you REALLY believe the switch from competition 2 strokes to 4 strokes is about the environment? I would encourage everyone to check out the comments I write here, to see for themselves, but, an F1 car race ( almost ALL F1 cars are made by Honda ) pollutes more in one full day of racing than every 2 stroke motocross bike did in an entire MX season of racing. Honda does not care anymore about the environment than they do about saving the 2 stroke. It's about money and how they are portrayed, when everyone "jumped" on the environmental wagon, so did Honda, they saw it as a way to push their inferior 4 strokes on a world full of "followers" and for the most part, it is working. They knew no one would win on a 4 stroke if the rules were fair, so they bought the AMA and the FIM and set out on their agenda. They make millions of dollars on parts alone, parts made from the earth, the same earth, they are trying to save. Come on, you really buying this crap?
Ren Schmidt -Pres. of Revanche2strokes.com  January 10, 2011 02:32 PM
All of this pro 2 stroke energy is great. However, we stroker fans have not "bought" into the big 4's agenda of pushing the inferior 4 strokes down our throats like the Kool-Aid drinkers have. What we should be doing is forcing the spineless AMA to right the wrong and make the rules fair in regards to the MX/SX nationals, then the real champions will re-surface and the 2 stroke will take it's rightful place atop the number one position. Having the rules fair in local racing does no good, what wins on tv, is what sells and until our machines win on tv, we will be relegated to 2nd class. The 2 stroke is a superior form and should be allowed to compete fairly. If I was a 4 stroke fan, I would be screaming for fair rules, I would want to know I beat the best and did it fairly, I couldn't stand rules that gave me every advantage and these rules made it so, that I couldn't lose. Sign the petition, support companys like ours who are fighting for them and support them at the races and in the dealerships. Soon the general public will wake, and see the crap the AMA is "shoveling" on them and, hopefully, they will go away, along with those who don't fair competition.
mx4ever1 -2T  January 8, 2011 10:32 AM
2T's rules. Here is why. 1- Lighter, That's a lot, 2- More hp per cc, 3- Easier to maintain & repair, 4- Cheaper to maintain & repair, 5- Lot easier to start, 6- Costs less, 7- Snappy and quicker rev, 8- Higher ground clearance, 9- Runs cooler ( Less danger to get burned ), 10- Less parts to worry about. People don't get fooled by the companies pushing their $ 4T. Last year I got fooled and bought an 450. From day one it was an night mare. I crashed over an bump due to engine bugged. Then it was starting night mare. And finally, The weight over the jumps and turns. Sold it and got back to 250 2T. Why would anyone buy one of those sucker 4Ts !?
Consumer -Adam-MotoUSA  January 5, 2011 12:35 PM
Last year I bought a 2010 KTM250SX because Yamaha's 250 smoker was almost $400 More. Can you believe that a KTM or any non Asian company was a cheaper deal! This year alone the Yamaha went up $250 more then when I was looking to buy.

kyle -2 stroke  January 3, 2011 05:53 PM
I have a 09 yz 85 and you just have to spend alot of time on the 2 stroke to get used to it. when your used to it the 2 strokes flat out go and can easily beat the 4 strokes. i have a drag strip and a bunch of riding buddies we always drag and i can beat my friends kx100 and my friends all stock race quad 09 kfx450 and i can beat it with ease. after putting vforce reed valves and a new exsaust and sinlencer this thing kills. bottem line if you plan on sticking with a bike for a season or 2 get the 4 stroke but if u want one longer than that 2 stroke is the way to gay mainly because the powerband on the 2 stroke is so touchy. you have to know them better than you know youre mom
YZ Owner -Above the Influence.  January 2, 2011 05:38 AM
First of all, please no commercial/advertisements here. Second, I do have a 06 YZ125 purchased brand new. I always hear complaints why no 2T in pro AMA races, or even in larger local/regional events. Solution: Vote, buy, influence. Corporations like Honda/Kaw/Yam are not unlike BP, Reytheon (makes so much money selling weapons to oversea customers) or Phillips Morris. They need to make MONEY. So they promote 4 strokes with explosive engines. What, you don't know AMA is in the pockets of OEM? Look at AMA road racing now. Sad.
Ron -Rancher you're wrong  December 31, 2010 07:57 PM
The 125 is the perfect transition bike between an 85 and a 250F. Have you even ridden a yz125?
kevin -2t's  December 30, 2010 07:19 PM
Guys, it is inflation. Corn, bread, beef, and milk have not changed in decades but they cost more today than they did 5-10 and more years ago. Cost of materials, labor, etc. keep going up no matter if the bike changes or not.

As far as 2t's go. They don't need our sympathy. They need the powers in AMA racing to pull their heads out of their a$$'s. They need to come up with a fair displacement for 2t's vs. 4t's. Allow 175cc 2t's to race the 250f class and allow, say, 300cc 2t's in the 450f class. I'm not saying these are the perfect displacements but you get what I mean. Get out of the 125 and 250 frame of mind and come up with displacements that are fair. It's not rocket science so obviously, if they wanted 2t's racing, they would use this common sense.

2t's don't need our nostalgic sympathy's. They are weapons and, given a fair shake, they are absolutely as competitive as 4t's.

adam - motousa -consumer  December 30, 2010 02:02 PM
i agree with consumer. im not sure why the price keeps climbing on this bike because it hasn't been changed in a few years. i would like to see a bigger price disparity between this and the four-strokes if that was larger i think companies would sell more two-strokes. regardless this yamaha yz125 is tits and i would like to get one for weekend racing and play riding.
rancher -transition?  December 30, 2010 12:19 PM
i thought the honda crf150r was the bike between the 85 and the 250? this yamaha 125 is a full sized bike and way too big of that kind of jump. it's really sad that the other three japanese makers are as agressive about the enviroment as well as the safty of our youth.
R34 -ummm...fun!  December 30, 2010 09:02 AM
Consumer -Price climber?  December 29, 2010 08:14 PM
Why has Yamaha raised their prices on 2strokes they really haven't changed...?? Answer; to sell 4strokes silly! It's a just a shame that a 125cc smoker has almost(and in some cases more) power then a 250cc thumper. But I can live with the higher sale price and small power difference because after the first 2stroke top-end rebuild I do, I'll still have money left to spend.