The Taiwanese wheel manufacturer Alex Rimsthe Swiss company DT Swiss, the Spanish rim manufacturer Rodi (since 2023), as well as the Dutch rim manufacturer RIDE (since 2025) supply or supplied Stromer with rims.
AlexRims - Cracks in spoke holes
The AlexRims rims struggled with cracks at the spoke holes. The cause could lie in the quality of the lacing or the base quality of the rim. My AlexRims rear rim on the ST3 was replaced at a mileage of 8,800 km and relaced by my dealer. It lasted just under 20,000 km until cracks reappeared. I rode another 10,000 km until I had to replace the motor mounts at 38,970 km, and at the same time switched to DT Swiss H612 and butted spokes (Sapin strong G13/G14) and 14 mm brass nipples.
There are also isolated reports of corrosion around the valve. However, this problem is likely to occur mainly on electric vehicles in winter use, where salt leads to increased corrosion.
Rodi - Cracks in spoke bores and broken spokes
Starting around mid-2023, rims from the Spanish manufacturer Rodi began appearing on new electric scooters. They can be identified by the silver eyelet at the spoke drillings, BLACKJACK hubs, and a small „RODI“ imprint on the rim.
The problem with cracks at the drill holes continues with Rodi. In addition, there have been an increased number of spoke breaks – as seen in forums and FB groups to read.
According to a post in the forum speedpedelcreview.com of July 4, 2024, the cause is still unclear.
Partial excerpts from the forum:
Stromer says that it is extremely difficult to find out the cause because, according to Stromer, an identical combination of parts used to cause no problems and is now suddenly causing problems...
In the event of structural problems, Stromer now has the wheels retuned by the dealer or an external wheel service. Several dealers are also said to have chosen different nipples and/or different spokes and therefore solved the problem. The ball is now in Stromer's court to ensure that the wheels are 100 % from the factory. (Source)
...Stromer has been discussing the solution for almost a year now, but has not even identified the actual cause, although it really can't be rocket science. And yes, wheels with broken spokes are exchanged for other wheels that are likely to break again. (Source)
ST7 with spoke breakages
Occasionally, in 2024, there were also Reports that the ST7 also has broken spokes (1 | 2 | 3) should exist. DT Swiss rims are installed there. In the past, these were inconspicuous on the ST2S and ST5.
Analysis
An analysis of the problems can be found in the speedpedelcreview.com forum. I quote here the translated version of the Wheel specialists Spaakshop in Belgium.
As a full-time wheel builder and specialist for heavy-duty wheels, I would like to comment here. I have re-spoked all Stromer wheels for a dozen bike stores in Belgium.
Not only Stromer, but also many other (speed pedelec) brands have problems with their bikes (e.g. R&M, Stromer, Klever, Opium, ...).
The reason is actually quite simple: saving on parts and quality.
Four causes:
1. Bad Rims: The rims used are actually too light for the heavy demands of speed pedelecs. Additionally, the holes are not drilled at the correct angle, especially for the large hub motors.
2. Moderately straight 14G spokes: For this type of wheel construction, I only use Sapim Strong spokes with reinforcement at the spoke elbow, but still a flexible spoke that can withstand impacts. Stromer and others use normal straight 14G spokes.
3. The nipples are not secured: This makes the nipples easier to loosen than secured nipples.
4. Quality of construction and control: The wheels are not strong enough for the load, and there is a large variation in spoke tension. This is known internally at Stromer, and a solution is being worked on, or at least that's what the dealers promise.For this, my partner RAD15 rims (a Dutch company specializing in small-batch rims) developed a special rim that's really quite strong, the Storm33 with a 33mm internal width, suitable for the wider tires of high-speeds. Their „STROOP model“ is specially drilled so the angles of the rim holes align well with the spoke patterns of the STROmer and OPium motors (which are almost the same motors in terms of dimensions).
These rims have now been adopted by Opium as standard guarantee rims and are also used by Ellio and Santos, among others. We also build these wheels with Sapim Strong spokes and Sapim Secure Lock nipples, which are secured nipples that prevent loosening.
The combination of these components and the precise craftsmanship results in a super-strong combination, hundreds of which have already left the factory and none of which have ever come back with problems. These wheels are also mechanically loaded with up to 300 kg during the construction process to simulate the toughest driving conditions.
The problem for dealers is that Stromer still gives dealers the same rims and spokes under warranty, so the problem is really just postponed to several months/years later. Plus, of course, the refund is not enough for the dealers, so I have many customers (ie stores) who add this themselves because they know our wheels are 100 % fine and worry free. I even have one dealer who already includes re-spoking in his lease as part of the maintenance cost, simply because he knows the likelihood is high... (Source)
Price tag: New spokes with the STROOP rim and reinforced Sapim Strong spokes and nipples cost around € 233 incl. VAT. A new front wheel with DT Hybrid 350 hub, tubeless costs around € 330.
Solution from myStromer AG
If there is a problem with the Rodi rims, the dealer can submit a warranty claim to Stromer. Stromer will then replace the rim, have it re-spoked or reimburse the dealer a lump sum (as read) if he replaces the nipples/spokes himself.
Customers report that the problem can recur even after replacing the wheel or repairing the rim with individual or all spokes and nipples (Source 1 | 2 | 3).
According to a Contribution From September 30, 2025, on stromerforum.ch, Stromer is replacing defective rims with the Andra 29 from Dutch rim specialist RYDE. This rim is designed for cargo bikes and is intended to better handle the stresses on the rear wheel of the Stromer. See also „Rims 27.5“ - Alternatives“.
Solution from retailers
Power traders in Holland and Belgium, a major power market, have been looking for solutions themselves. They identified the problem with the eyelets/spoke drilling of the Rodi rim in combination with the nipples used, their length, and the relatively large deflection angle of the spokes on the rear wheel. Furthermore, there seems to be a wide variation in the quality of lacing. The spokes are not secured and can loosen. An excessively high system weight (max. 150 kg for 27.5″ models) is also said to exacerbate the problem.
The solution of the aforementioned retailers is that longer Spoke nipple (14 mm instead of standard 12 mm) or Brass nipples to be used. A complete re-spoking with replacement of all spokes does not seem to be necessary. If the defective spokes and all nipples are replaced with brass or aluminum nipples of 14 mm, that seems to be sufficient, at least according to customer feedback.
Nipple recommendation
- SAPIM: Polyax brass Ø 2 mm | length=14 mm (e.g. for bike24.de)
- DT Swiss: DT Pro Head, Brass (12, 14 mm)
Spokes
If you also want to replace the spokes, you can use the DT Swiss Champion spokes 2.0 J-Bend, black, 188 mm buy. This fits, for example, the DT Swiss H612 rim.
If you want even more stability, you can use the Sapim Strong Spokes (13G/14G single butted) J-Bend Black – Use 189 mm. And it is recommended to treat the spokes with threadlocker to prevent loosening from operation later on.
Alternatively, you can also DT Swiss Prolok nipple can be used.
Alternative rims - 27.5″
Alternative rims are one way to solve the problem once and for all.
See Kapitel – ,Alternatives - 27.5″ rims' / (Spoke calculator / Spoking)