Endurance test final balance: Yamaha YZF-R 125

Table of contents

Endurance test final balance: Yamaha YZF-R 125


Endurance test final balance: Yamaha YZF-R 125

Endurance test final balance: Yamaha YZF-R 125
The Yamaha YZF-R 125 after its endurance test

Who would have thought that life at the lower end of the displacement scale could be so enjoyable? The YZF-R 125 demonstrated a lot of stamina over 25,000 kilometers and was even more enjoyable.

Andreas Bildl


In this article:

  • Endurance test final balance: Part 2
  • Readings
  • Balance after 25,000 kilometers
  • Costs and maintenance
  • Reading experience
  • Yamaha takes a stand…
  • Used Yamaha YZF-R125 in Germany


Buy complete article

Endurance test final balance: Yamaha YZF-R 125

Endurance test final balance: Yamaha YZF-R 125
The Yamaha YZF-R 125 after its endurance test

9 pages) as PDF

€ 2.00

Buy now

wise, a 125cc does not attract much attention from the MOTORRAD testers who are spoiled for performance and displacement. And so far, with the Hyosung GT 125, only one representative of this displacement class has got lost in the long-term test fleet. But this time things were a little different.

From day one, little Ypse had a stone in the editorial board. With its close visual proximity to the super sports cars R6 and R1, it not only nodded appreciatively everywhere. She was neither avoided nor spared, but welcomed with open arms and quickly chased through her test program in 21 months.

Not only did she benefit from her rather grown-up demeanor. Rather, it was solid qualities that made them a welcome companion even for longer trips. The lively engine in particular received a lot of praise. Already 5500 rpm were enough to easily swim along in city traffic or to leave dreamy drivers standing at traffic lights.

Thanks to this characteristic, warming up after a cold start was not a problem either, since in the city you did not mutate into a hiking chicane even at medium speeds. And from 8000 rpm, the little single put on a few more briquettes, with which even overtaking maneuvers on the country road could be mastered quite quickly. If he was in a good mood or even had a tiny incline as an accomplice, then in the wild he turned cheerfully into the red area, where the limiter waits at 10,000 rpm. Which, according to the speedometer, was 134 km / h.

Endurance test final balance: Yamaha YZF-R 125


With the right tires, the Ypse awakens the thirst for action even in the wet.

Whether twice in autumn or once Magny-Cours and back, the YZF-R 125 got around quite a bit. The amount of space available also enables taller pilots to master longer tours without having to go to an orthopedic surgeon. And if the handlebar stubs were too low, it was relatively easy to help with small, self-made spacer bushes, which bring the handlebars a few millimeters higher (see endurance test interim balance, issue 13/2009). A little more information in the cockpit, such as a clock or a second trip counter, would certainly not be an exaggerated luxury, especially on longer tours.

But the really astonishing thing: Although constant full throttle was practically constant companion, the little one sucked Yamaha on average only a modest 2.9 liters of super per 100 kilometers through the injection nozzle. She was so economical with the expensive raffinate that some drivers wondered whether the fuel gauge was broken. In the absence of any significant oil consumption, it was only necessary to refill lubricant over the test distance once. And even after frosty nights, the Yamaha had no problems responding to the starter’s wake-up call immediately. A very strong performance that the single-cylinder, built by Minarelli in Italy, delivered. In addition, a smooth clutch and a smoothly running gear, heart what more could you want?

At best, sensitive natures can accuse it of a somewhat pronounced mechanical background noise. But nothing more. Second asset of the pocket racer: the chassis. Stable and manoeuvrable, equipped with a great front brake, makes it really fun to bend the red and white speedster around corners. However, the driving pleasure depends heavily on the tires. The Pirelli Sport Demon, with which the Yamaha approached the editorial underground car park when starting work, are convincing in both dry and wet conditions. The Michelin Pilot Sporty, on the other hand, are not very happy.

The French rubber apparently often used in the original equipment is then also remarkably often the subject of complaints in readers’ letters. It should be used with caution, especially when it is wet, as its grip is then strictly limited. Which doesn’t exactly correspond to the entry-level idea of ​​a problem-free 125cc. However, the Yamaha is in great shape with the Bridgestone BT 45, which – see the interim endurance test in issue 13/2009 – is a real tip in all weather conditions.

Endurance test final balance: Part 2

Endurance test final balance: Yamaha YZF-R 125


On longer tours, the YZF-R 125 demonstrated outstanding standing qualities. So it’s no wonder that she had her 25,000 kilometers together so quickly.

“Where was that thing when I was 16?”, colleague Gerhard Eirich sums up his enthusiasm mixed with melancholy. Now slowly, only praise and nothing to complain about? Well, basically not. Because the only defects that overtook the Bonsai-R1 were a loosely vibrated plug connector at mileage 11672, which was done with a flick of the wrist. And shortly afterwards a broken link on the drive chain, which was then replaced during the upcoming inspection. The newly installed one, however, only lasted a surprisingly short 5000 kilometers. What further depresses the cost balance is the oil change that is due every 3000 kilometers. Amazing, because the same engine in the WR 125 doesn’t need it.

It has to be inspected every 6,000 kilometers. The costs for this were still within a pleasing range at around 160 euros. Only the 12000 maintenance was much more substantial at 479 euros. However, it also includes brake pads and the chain set mentioned above. In the course of this, the tank was also replaced as part of a recall campaign.

It was only when the Yamaha turned onto the home straight that somewhat stronger mechanical noises came out of the engine and seemed to have lost some of its top speed. Which is also reflected in the somewhat weaker performance at the end of the test. The final compression diagram did not show any abnormalities, however. And the final step on the dyno roller certified the YZF-R 125 still strong 14.5 hp. However, with significantly increased power loss.

So what would dismantling bring to light? First of all, nothing spectacular. All four valve seats tight and not knocked wide. The valves themselves without undue carbon deposits or shaft play. The camshaft and roller rocker arm are also still in good shape.

Endurance test final balance: Yamaha YZF-R 125


The Yamaha proved to be a reliable companion for all occasions.

Only the piston skirt showed clear signs of running. The piston running clearance and the piston ring joint clearance, however, are completely in the dark green area. And the cylinder has also kept itself free of damage and shows neither wear nor ovality. It continues in this style. The clutch plates must have gotten really bored, because the thickness of the friction disk was still well within the installation tolerance. Transmission gears, tiptop. The roller-bearing, one-piece crankshaft can also move back into the crankcase, as can the water pump. The shift drum looks as robust as if it came from the FJR 1300, and the shift forks show only minimal tracks. Anything else would have been a surprise, given the switch box that worked precisely right up to the end. It is therefore possible that the O-ring chain installed instead of the original single chain was already worn and was the cause of the higher power loss in the final power measurement.

However, the Yamaha did not get away with it completely. The shock absorber has lost its cushioning and thus comfort over the distance. The toothing for the pinion on the gearbox output shaft has broken out of material (see: “Yamaha takes a stand…”). In addition, the front brake disc had to be replaced shortly before the end of the endurance test; its wear limit had been reached. And the brake pads were also due for replacement for the second time. Otherwise, however, the YZF-R 125 is still clean after 25,000 kilometers. The motor housing looks a bit worn, but otherwise the paint quality is good, there is nowhere noticeable rust or sloppy plug connections offend the eye. The bearings of the swing arm, steering head and wheels are still flawless. The processing is therefore on a similar level as its driving dynamics qualities. Somehow it’s a shame that the 25,000 kilometers are already over.

Endurance test conclusion:
After this endurance test, it is completely clear why the YZF-R leads the registration statistics for the 125 cc and is the top seller at Yamaha. At just under 4,000 euros, it is not a special offer. But you also get a lot on offer. The chassis, brakes and engine impress with their dynamic qualities and stability. On top of that, it is easy to use. So you don’t just lure 16-year-olds out from behind the stove. Still, there is room for improvement, particularly in terms of tires and chain and brake wear.


Endurance test final balance: Yamaha YZF-R 125

Drawing: archive

Power on the crankshaft; Measurements on Dynojet roller test stand 250, corrected according to 95/1 EG, maximum possible deviation +/- 5%

Initial / final measurement 1310 km / 24 370 km

0-50 km / h sec 3.7 / 3.9
0-80 km / h sec 8.9 / 9.3
0-100 km / h sec 15.7 / 16.5

50-80 km / h sec 12.6 / 13.9
50-100 km / h sec 22.0 / 24.5

Average fuel consumption over 25,000 km

Fuel (super) l / 100 km 2.9
Engine oil l / 1000 km <0.1

Balance after 25,000 kilometers

Endurance test final balance: Yamaha YZF-R 125

Drawing: archive

The wear diagram of the Yamaha YZF-R 125: Everything in the green area.


Cylinder head: All valves tight, the valve seats hardly widened. The valve guides show only slight wear. The camshaft with roller bearings and the rocker arm rollers are also in good condition.

Cylinder / piston: The compression has decreased somewhat, there are marked running marks and heat discolouration on the piston, but the piston play is okay. There are only slight tracks on the cylinder liner, the diameter and shape of the cylinder are within the tolerance range.

Crank drive: The axial and radial clearances of the roller-bearing crank mechanism are within the tolerance. The piston pin and the connecting rod eye are in good condition.

Power transmission: The clutch is hardly worn. The shift forks show harmless tracks, a tooth has broken out on the pinion receiving toothing of the output shaft.

Frame / chassis: The processing of the frame, chassis as well
the plastic parts make a good impression. The rear brake disc is worn out, the damping of the shock absorber has decreased.

Costs and maintenance

Endurance test final balance: Yamaha YZF-R 125


Honey, I shrunk the superbike Strong appearance of the YZF-R 125.

Operating costs over 25,000 kilometers:

8 liters of oil at 12.23 euros – 97.84 euros
5 oil filters at EUR 6.17 – EUR 30.85
2 air filters at 12.49 euros – 24.98 euros
2 spark plugs at 8.4 euros – 16.80 euros
2 sets of rear brake pads at EUR 44.10 – EUR 88.20
2 sets of front brake pads at EUR 44.10 – EUR 88.20
2 chain sets of 99 euros each – 198.00 euros
1 brake disc – 159.48 euros
Small parts, lubricants, seals – 59.16 euros
Inspections and repairs – 830.71 euros
Tires (including assembly, balancing and disposal) – 235.12 euros
Fuel – 945.41 euros
Total cost – 2774.75 euros
Acquisition cost – 3745.00 euros
Loss of value – 1445.00 euros
Estimated price (dealer selling price) – 2300.00 euros
Costs per kilometer (without depreciation) 11.1 cents
Costs per kilometer (with depreciation) 16.9 cents

Maintenance and repair costs:

Spark plug cap vibrated loose at km 11672
Chain set (link was broken) as well as front and rear brake pads renewed, tank renewed (recall) at km 11848
Michelin Pilot Sporty renewed tires front and rear at km 13,711
Front and rear tires renewed Bridgestone BT 045 at km 14624
Chain set renewed at km 16531
Front brake disc, front and rear brake pads renewed at km 23572

Reading experience

Endurance test final balance: Yamaha YZF-R 125


The reader Oliver Beilke on his Trentino Dolomites tour with the Yamaha YZF-R 125.

Not driven for 22 years, then little Ypse came along!? The photos show our 2009 Trentino Dolomites Tour on the way to the Stelvio Pass (2720 m). And that with a 125! With my 41 years of age (unfortunately still no big driver’s license) and over 100 kg live weight uphill, of course, I can’t win a race, but you can keep up, brakes, engine, chassis, everything is great! But alas, it’s going downhill … the Mendel Pass was the most fun. To the point: big praise to Yamaha, really a great machine!
Oliver Beilke, Neuss

Since a half year I am an enthusiastic driver of the Yamaha YZF-R 125. The lively engine impresses in cooperation with the stable Deltabox frame and offers driving fun, especially on winding roads. Even if you have to correct the course in the curve or throw the anchor, it remains stable in the desired lean angle. The absolutely reliable and sporty, ambitious engine is praiseworthy. It starts immediately even at the lowest temperatures (minus seven degrees). Not to mention the precise gearbox and the easy-to-dose, smooth-running clutch. Although, in my opinion, the fifth and especially the sixth gear is too long, in contrast to the first three gears, there is noticeably a lack of steam. The sporty look is also impressive, it not only makes a very good impression on the school car park, it also amazes seasoned motorcyclists. A pillion passenger is not comfortable, but acceptable. Yamaha probably currently has the best 125 cc on the market, which boasts a successful balancing act between sportiness and suitability for everyday use.
Kai Strycker

I already have 10,000 kilometers now ridden my Yamaha. Basically I am quite satisfied, but I also have a few complaints. The very low consumption of between three and 3.7 l / 100 km is good. It also runs very smoothly, the Brembo brakes respond well, and for its four-stroke engine it also has comparatively good acceleration. In addition, their purchase price at the time of purchase was relatively far below the competition à la Aprilia RS 125 or Cagiva Mito. In my opinion, the chassis of the R 125 is not built for sporty driving. A big drawback is the standard tires, at least if they are called Michelin Pilot Sporty. In bad weather and / or low temperatures, it is just dangerous. I don’t know what Yamaha rode to put this tire on the R 125. It takes forever to warm up, and if it is tilted a lot, it tends to slide. However, the driving behavior has changed positively with Bridgestone BT45. Despite regular maintenance, the standard chain ran out very quickly. On the R 125 I would have liked a firmer chassis, an upside-down fork, wider tires and a more powerful engine from Yamaha. All in all, however, it is a very reliable motorcycle that starts immediately and (at least for me) had no defects. It attracts attention and is often thought to be bigger than it really is. It is a great everyday motorcycle, but inferior to the competition when used for sporty purposes. I really enjoyed my two years with my Yamaha, but next time I would choose an Aprilia RS 125.
Tobias Schneider

Both me and my parents were enthusiastic at first sight. The first few days with mine “red and white racer” My parents saw me only driving away in the morning in motorcycle clothes and in the evening exhausted, but coming home with a big grin on my face. I drove the Michelin Pilot Sporty for the first 6000 km. In the dry, I was extremely satisfied with it. But the grip qualities in the wet are bad. On the following inspection, I wound up Bridgestone BT-45. One of the best decisions in my opinion. Very good both in the wet and in the dry, and the minimum tread depth was still present after 8000 km. A huge plus point of the Yamaha: the fuel consumption! Their 13 liter tank capacity is enough for at least 350 km even with brisk driving style. The little Japanese girl’s driving behavior is breathtaking. For a novice driver, it is perfect after a few kilometers, and the ‘little one’ is a lot of fun even for experienced drivers. After 25,000 km my conclusion: Long distances over 800 km on the highway as well as short distances to eat ice cream, my white and red racer never caused the slightest problem. I can do that for all newbies to motorcycling Yamaha YZF-R 125 Highly recommend.
Marcel Hildmann

So far there are 4239 km on the speedometer and I can actually only say good things about the machine. You sit pretty well (at a height of 178 cm), and I also get along perfectly with the spring adjustment. You have the machine well under control even on uneven roads. What I find only partially good is the fork, which plunges very deeply during strong braking maneuvers. The main focus of me and many forum members: the standard tires “Michelin Pilot Sporty”. We are of the opinion that the tires are completely unsuitable for beginners. This is not really good as Yamaha is trying to appeal to the younger generation as this is the generation with no experience. The tire is very difficult to control for beginners and has poor cornering properties. The engine is great to drive. He has a nice pulling force in all speed ranges. A straight route is required. The YZF runs out of breath on a winding and uphill stretch and you can’t stop shifting, but that’s understandable for a 125cc four-stroke engine. The fuel consumption is very humane. I drive them with an average of about three liters.
Harald Rauer

Yamaha takes a stand…

Endurance test final balance: Yamaha YZF-R 125


Yamaha representatives Karl-Heinz Vetter and Ralf Keller (from left) examine the engine parts with the author and workshop boss Gerry Wagner.

…to break out material on the toothing for the pinion on the gearbox output shaft.
It is surprising that no traces of material were found. Maybe the part was a minor manufacturing error. We would continue to use the wave without hesitation.

…the service life of the secondary chain and the broken plate.
The quality of the chains has meanwhile been improved and we assume that such damage no longer occurs today.

…to the criticism of the first tires Michelin Pilot Sporty.
We accept this criticism and are happy to pass it on to product planning. The Michelin Pilot Sporty, however, offers a long service life, which is an important aspect especially for young people.

…to the tracks on the piston.
From our point of view, this is only a visual flaw, since the piston and cylinder are still in the area of ​​the installation tolerance or in the initial area of ​​the operating tolerance. In our opinion, the traces are possibly due to a bit too short warm-up phases while driving.

…to wear on the brake system.
The degree of wear on the brake discs is only slightly below the manufacturing dimension, so it has a very low tolerance. Since the brake was still working perfectly, it shouldn’t be viewed as critical, but you should still change the disc.

…to the lean cockpit.
Especially for products in this price range, calculations are consistently made with a sharp pencil. We are also happy to include this point as a suggestion for product planning.

Used Yamaha YZF-R125 in Germany

Endurance test final balance: Yamaha YZF-R 125

1000PS marketplace app

The selection of used Yamaha R125s is large.

The Yamaha R125 is one of the most popular A1 motorcycles on the market and you can feel it on the used market. The choice is wide and the prices start very low. Various copies have already installed accessories, but most are original. Here is an overview of the used market: used Yamaha YZF-R125 in Germany.

Leave a Reply

Your email address will not be published. Required fields are marked *