Vespa Polini 210, bgm PRO 60mm, Dellorto SI26 - Tuning test engine - Part 3


The carburetor and intake area are prepared.

Now we can fill the engine with the parts we still need.

The 4 speed levels are in the form of a Px200 transmission built-in.

Switch cross and gear wheels are mounted accordingly.

The switch cross should be something threadlocking . use

Gear wheels, Seeger and Shoulder rings can then then be draped to create a pretty overall picture.

The play of the gear wheels should be in the range of 0,05mm-0,15mm during installation. It is best to control the existing game with 2 Feeler gauges. With new shoulder rings you can choose the game tighter, since the bearing surfaces of the shoulder rings shrink even more over the first few kilometers than with already used shoulder rings.

The crankshaft still gets even with that suitable tool missed the inner ring of the alternator bearing.

And the Ball bearing set implanted.

The ball bearings are with Cooler spray cooled and gently brought into your bearing seats by heating the housing halves.

Exceptions are the two needle bearings in the “small” half of the alternator housing.

The Alternator bearings should be safe with the matching tool be guided.

The B188Bearings for the main shaft have to be given a little extra, 1000gr. in shape a hammer should be enough as gentle intercession.

Once all the bearings have found their place, they will Shaft seals assembled and puzzles with the Needles of the spurious consequences. The individual needles with fat fixing helps a lot. You should still have a steady hand. Don't forget to count, 21 needles should work here.

Kick starter pinion and Segment are the last missing components.

Do not forget! the Pressure spring the kickstarter sprocket is best glued in with grease.

The crankshaft is installed and the housing assembled.

With the torque wrench, everyone will Housing bolt evenly tightened.

The oil pump drive is installed.

The Worm wheel is from 2 Thrust washers flanked. The one is missing in the picture below Seeger ring serves to secure the worm wheel.

Nachdem die Oil pump shaft mounted with a little oil can do that pinion placed on the crankshaft and mounted the clutch. Most crankshafts have a small radius towards the coupling stub on the coupling side. Therefore, the bevel of the pinion should point towards the crankshaft during assembly.

Here in the installed state you can see how nicely the dust lip on the wider sealing surface of the bgm crankshaft protects the actual sealing lip.

The most important link between the gearbox and the crank drive is the clutch.

Therefore we rely on the tried and tested bgm Superstrong clutch.

Designed for 10 springs, the Superstrong offers a lot of possibilities to vary the spring stiffness.

In our case we are using 10 XL feathers.

Dhe shaft-toothed hub is used with oil.

Clutch pinion and the Topping packt with steel discs consequences.

When installing the pads for the first time, you should add a little oil.

With the steel disks you have to pay attention to the positioning of the Washer with the notches respect, think highly of.

This is deliberately deformed by a few 1/10 mm in order to immediately create the clearance when the clutch is actuated so that the clutch separates cleanly.

Is the topping package and the Locking ring mounted, the coupling is ready for installation.

By the way, all complete bgm-Superstrong couplings are pre-assembled for you in exactly this way. Including adjustment of the clearance and control of the freedom of movement.

The self-locking Collar nut we fastened with 60Nm.

Now that the engine has been put together so far, the cylinder can be attached for testing purposes to measure the control angle. Nice job for tomorrow :-)


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