Out of frustration about the quality of the spare parts available or due to the fact that for some needs there is no product offering at all, I started to rebuild parts for my own use in larger quantities.
Reinforced spring for rearshock Wideframe/GS150:
This spring is about 30% harder, progressive and cylindrical. This makes it possible to easily carry loads and an additional passenger, without having the impression of constantly driving uphill. In solo mode the suspension appears firmer and the scooter is more agile overall. The spring is designed to fit on both the Italian shocks and the German Boge dampers.
Because of the cylindrical shape keeps the spring away from the tire and clutch cover.
Reinforced front spring ( until '54, short swingarm, without shock):
The original spring is aged and much too soft. Together with the short swingarm the steering feels wobbly. The about 30% harder spring provides significant improvement especially when driven hard on bumpy streets and with tuned engines.
Nagy-Blechroller inlet manifold for 125cc-motors (beginning 1948):
The manifold has an inner diameter of 23mm and an outer diameter of 28mm. It is intended for the use of larger carburetors (e.g. 21 or 23CP Polini) on your 125cc wideframe engines. He is painted and sandblasted, so that rubber is fixed and carburetor cannot twist off. The connection rubber can be supplied on request.
When you think about tuning, you have to use a larger carburetor in conjunction with this intake
This is how it looks when installed in your 125cc motor:
The basis for tuning your original Wideframe cylinder is the right spacerkit. This is the only way you can sustainably and meaningfully change timings and porting. With this set you can bring your engine with suitable peripherals to easy 8 HP.
As already mentioned:
With modifications and tuning measures, the vehicle looses its legal street registration and may only be moved on non-public, racing locations!