If you have a certain weakness for powerful motorcycles, then scooters tend to take a back seat and one is inclined not to take such vehicles entirely seriously. One is encouraged in this opinion by the fact that the scooter models that have been offered in the GDR so far, while very well-behaved, but were not particularly stunning in terms of horsepower. 125 ccm are now only 1/8 litre. Neither colour nor shape make much difference.
The first scooter that was more convincing in terms of its performance was the Cezeta scooter with a displacement of 175 cm3. This, we call a "touring scooter", has now received a similar counterpart in the "Berlin" scooter, which, although provided with the abbreviation SR, or City Scooter, can be described as a touring scooter in the same vein as the Cezeta.
This is actually the most appropriate characteristic for this latest vehicle from our nationally owned industry. With the further development of industry and with the expansion of the supply of industrial goods, people have become more critical and also place higher demands on motor vehicles. IWL has obviously adjusted to this and is bringing a suitable vehicle onto the market.
The most striking features of this scooter are the 150 ccm engine, which has a maximum output of 7.5 hp, and the four-speed transmission. In all other parts, the scooter is not new because the tried and tested components of the SR 56 Wiesel were used. Nevertheless, apart from externally recognizable features, the "Berlin" scooter distinguishes itself quite noticeably from its older brother through its ‘liveliness’ and its smoothness.
We wrote as the final sentence in our Wiesel test in issue 11/57 of our magazine: "... it is quite possible that the tried and tested MZ motor could be brought up to 150 cm in a scooter edition. This corresponds to 6 HP and then the Wiesel will probably come close to the performance of the MZ 125."
So that's exactly what happened. The horsepower of the new scooter exceeds our careful estimates at the time. The scooter has a top speed of 83 km/h with a large man aboard, but a lighter person could achieve a speed of over 85 km/h. The scooter itself weighs 183 and a half kilograms and is 183 cm in length. Is that nothing? The prophecy of 1957 has thus come true with regard to driving performance. It can be seen that there is also some acceleration in it. The values can be found on page 354 above.
This means that the scooter has not become a super-sport experience and demanding drivers may turn up their noses. And they may! The scooter was not designed and built for such drivers. Let's keep in mind - scooter drivers are mostly first-time vehicle owners. You just want a scooter and nothing else. You make demands on this scooter, most of which are not yet of the real capacity of such a vehicle.
In terms of maximum speed, traction, acceleration and also braking deceleration, the Berlin still has noticeable reserves for such drivers. If you want to drive fast, you must know exactly how much you can trust your brakes, what you can trust of its driving characteristics. First of all, here are the braking values. From 40 km/h the scooter stopped in 14 metres when using both brakes. This corresponds to a normal deceleration of 4.4 nvs2. The foot brake alone brought 3.4 metres per second or 18 metres braking distance and the handbrake 3.5 metres per second or 20 metres braking distance. These measurements were carried out several times in both directions in dry weather on the motorway. The braking distances are of course considerably longer on wet roads.
Now to the driving characteristics, although almost nothing was changed on the front suspension of the Berlin compared to the Wiesel, except that the spring travel was 10 mm longer, there were several unpleasant overruns in gusty side winds. If a gust of wind drove under the front fender, then the scooter would pull away in the front, especially if in curve. So, if you want to push the scooter to its limits, this is something you should take into account. The only possible explanation for this behaviour is that when you drive faster with the Berlin, the front grip is lessened and then the conscious unsafe feeling can be felt in the steering when there is a strong wind. At least 80 percent of all Berlin drivers will, however, never feel this, because such driving will not apply to them. As far as the suspension is concerned, we believe that the chassis of the scooter has been improved by installing a rear shock absorber, so there are no longer any concerns due to the chassis. We soon had a shock absorber installed in the front of the ID 05-15 (one of the first Pitty’s) and had great experiences with it. We missed this damper with the Wiesel, with the Berlin it is almost absent. We know exactly how our industry calculates, we also know that the scooter Berlin is ‘almost the same as the scooter Wiesel but with some not very cheap improvements, but perhaps the IWL could think of this missing shock absorber at the front as a further improvement.' Vibrations occurring in certain speed ranges are not very pleasant. It is questionable whether something like this can ever be removed completely. With a scooter there are a lot more possibilities than anywhere else to amplify vibrations, which always occur in vehicles, and to make them unpleasant to feel and hear. So it was only in the last few days that we found out where the whirring noise that occurs at a certain speed had come from, which irritated us for weeks. The kickstand attached to the non-cushion side starts dancing in fourth gear at around 70 km/h, and taps against the cast floor plate, thus transmitting these noises to the entire body. If a rubber shoe were put on the kickstand at the factory, this problem would be eliminated.
Another noise is also noticeable while driving. This is the whistling sound of the fan, which increases with increased speed, which in turn proves it is working! You would hardly need the blower control lamp in order to notice that the V-belt failed (by the way, this never happened with us after 3500 km of driving.
The exhaust and intake noise is very quiet, but how can you adjust the carburettor of the scooter Berlin correctly, if you cannot get to the carburettor through the intake damper? If you adjust without the intake damper, then it is correct. The fitting of the silencer is not exact and with the intake damper it does not work or becomes almost a life's work. It is therefore best to adjust the carburettor according to the manual values, if necessary. Exact details about this can be found in the operating instructions, which should also be reissued, because the photos shown do not match some of the actual features of the scooter.
With these manual values you don't perform too badly. The maximum speed has already been mentioned. The fuel consumption when driving very smoothly with a mixture of 1:25 Hyzet two-stroke oil/red fuel, is about 3.3 litres per 100 km. The information of the work in the manual is honest and can really be taken at face value. It may be necessary to make the following observation about fuel economy. Various SR-59 owners reported consumption at around 3 litres - yes, we even heard something of 2.8 litres per 100 km. That would of course be very cheap, but definitely not unlikely.
One more of side note: we would advise against using white fuel with this scooter, which has a compression ratio of 8.
Actually, we wanted to stop here after we spoke to two scooter instructors who recently drove their newly purchased Berlin from Weimar to Berlin without seeming to know how to actually get to the spark plug. Any further observation of the Berlin scooter puts us a little out of place, but since there are certainly a large number of other Berlin drivers and interested parties out there, a short, brief technical description of the Berlin scooter follows.
The main part of the chassis is an electrically welded central tubular frame, which does not differ significantly from that of the Wiesel scooter, but has been reinforced at individual points.
At the front, a so-called rocker arm fork is used, which has 110 mm (100 mm for the Wiesel) of spring travel. The road bumps are absorbed by proportionally acting coil springs. Unfortunately, a shock absorber is missing here, so that the undamped suspension lets the front part of the scooter move.
The rear wheel is mounted in a swing arm with a trapezoidal guide. The rear swing arm was mounted on the central tubular frame in the middle of a torsion bar by a hydraulic shock absorber dampened and secured against puncturing by ring-like rubber components. The front wheel hangs with a normal axle in the swing arm with dropouts, the rear wheel is attached with a thru axle. Both wheels can be changed quickly and easily.
The mono-block engine is exactly the same as that of the MZ 125, but has a displacement of 150 cm. The fan required for cooling, working under pressure, is very powerful and enables the motor to always work in the correct heat range. The impeller is driven by a V-belt that runs over a drive disc that sits on the toe shaft stump. The V-belt can be changed quickly, if not without getting dirty fingers. A replacement V-belt is supplied from the factory in the tool kit. On the right of the crankshaft is the voltage-regulating direct current light bulb, which has an output of 60/90 watts. The alternator is a unitary alternator developed for the entire motorcycle industry.
In contrast to the Wiesel scooter, the Berlin scooter is equipped with a four-speed gearbox which - apart from the greater liveliness of this vehicle - has a particularly favourable effect on fuel consumption because the engine speed is more economical under all loads (for comparison, the gear and power diagram).
The N241 carburettor from the Berlin carburettor factory is still a flat slider carburettor with an additional air slide as a starting aid. In the foreseeable future, a round slide carburettor should be expected for the Berlin scooter, which offers an even better possibility for mixture formation and sometimes excludes the possibility of problems in the partial load range. Upstream of the carburettor is an intake damper with wet air filter.
The power transmission from the engine to the gearbox and from there to the rear wheel is carried out by chains. The secondary chain is encapsulated in rubber tubes and can therefore be operated for a particularly long time. The few greasy areas on the scooter are easily accessible. The brakes were taken over unchanged from the Wiesel. If used correctly, they meet the requirements the scooter at any time.
We do not write about the gearbox damage that constantly occurred on our test scooter because we know that it only occurred in the first 1000 units in the series. So much for that. If authorized IWL workshops send owners who call in about this gearbox damage with the remarks that these are shift errors by the driver, they have absolutely no understanding. Such defects must be eliminated. One more remark about the seats of the Berlin. If you are doubtful, it is considerably more comfortable than the bench, but they have a disadvantage. Instead of the foam rubber filling of the ES motorcycles, the Berlin seats springs, which you can feel very clearly after a certain running in. Due to the springs, there is also no good lateral support as with the ES seats of the controller, whose protective hood is very easy to tear off when removing and putting on the rear fairing. In addition, during our test, the contact lugs for the brake and taillight on the fairing hood broke off, because their material was of course too brittle We also noted the constantly loosening exhaust union nut and the black, non-chrome-plated exhaust, which already had a rust finish after only 3000 km. The reflector is hardly adjustable. That has to be changed. The keyword to this: MZ ES.
Our overall assessment of the scooter - the Berlin is very positive despite this or that complaint. At the same price as the "SR 56" the "SR 59" offers noticeably more than its predecessor.
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