Stromer models with a chain have a motor located in the hub motor. Freewheel. It is an independent mechanical component and connects the motor to the cassette. It decouples the cassette, chain and cranks from the driven rear wheel so that they do not continue to rotate when you roll without pedaling. The rear wheel is therefore able to overtake the stationary crank in terms of speed, which is why freewheels are also called 'overrunning clutches'.
Type
The Stromer freewheel is a pawl freewheel. For the models ST7 | ST5 ABS | ST5 2018 | ST3 2018 | ST1 LCI | ST1 2019 it is a Cannondale Formula freehub body (FH-528 -11 gears).
The pawls and the spring are not available individually from Cannondale. As the user Henry In the NL-Stromerforum, as can be determined in a self-experiment, almost identical freewheel units from DT Swiss can be used. They are slightly less high and symmetrical. They are said to be even quieter in operation than the originals.
Defects / repair
Defekte sind selten und entstehen meist durch falsche Montage. Eine Reparatur des Freilaufs ist möglich, allerdings fraglich beim Originalpreis von ca. € 50.
The individual parts are not available as a repair kit, but you can buy them separately.
- Inventory: 2 pcs. 15x28x7mm (6902)
- Thread: Diameter 26 mm
- Sperrklinken: original nicht erhältlich. Alternative: DT Swiss 8×8
When removing the rear wheel, make sure that the freewheel is only attached and can come loose together with the cassette and fall to the ground.
Für die Montage muss ein geeignetes Fett (kein Öl) verwendet werden, z. B. das Park Tool HPG-1 Park Tool high-performance grease.
It is important to ensure that all locking pawls are clean and properly engaged in the freewheel receptacle of the motor. See Installation video.
Ein Fehlerbild kann ein festgebackener Freilauf aufgrund fehlender oder falscher Schmierung sein. Die Sperrklinken verlieren dabei ihre Funktion.
Speaking of lubrication:
Es reicht, wenn die Sperrklinkentaschen mit einem Tropfen Fett geschmiert werden. Bei der Verzahnung im Motor reicht ein Schmierfilm. Ist zuviel Fett eingetragen, kann dies durch die Motorabwärme (bis 150 °C) zu einem Verbacken der Klinken und somit zu einer Blockade führen.
What bearing is used on the st3 pinion rear wheel free hub.
Mine needs replacement as it had moisture ingress and corrosion so is now a bit rough.
Purchased late 2024, over 15,000 kms.
There is no 100%% verified information on the internet about the bearings used (6902 / 6802?), at least I haven’t found any. The thru axle on the ST3 has a diameter of 12mm.
Due to the relatively low price of a new freewheel body (approx. €50 depending on the supplier), it is questionable whether it is worth the effort to replace the bearings individually.
https://www.google.com/search?q=FREEHUB%2BFORMULA%2B11%2BSPEED%2C%2B3-PAWL%2BFREEHUB%2BFOR%2BAXIS%2B142x12& oq=FREEHUB%2BFORMULA%2B11%2BSPEED%2C%2B3-PAWL%2BFREEHUB%2BFOR%2BAXIS%2B142x12& gs_lcrp=EgZjaHJvbWUyBggAEEUYOTIHCAEQABjvBTIKCAIQABiABBiiBDIHCAMQABjvBTIHCAQQABjvBTIGCAUQRRg8MgYIBhBFGDwyBggHEEUYPNIBCDUwMzlqMGo0qAIAsAIA& sourceid=chrome&ie=UTF-8