Selling E-Bike Tuning Kits; Implications & Legalities


Well-Known Member
Piedmont Highlands
"In particular e-bikes fitted with 25 km/h Bosch systems are easy to tune with a widely available kit. It’s simple to make such bikes capable of a 45 km/h top speed. However, Bosch is able to track the possible hampering of each individual drive system when logged on for possible malfunctioning of the system. When hampering is ascertained the regular 2-year warranty is cancelled."
In other words, pony up for the s-pedelec version or your warranty is void, right?

To your 2nd post - don't they have anything better to do with their time? what a waste of resources.
"...dealers can be held fully liable for all damages." (In case of accidents) - obviously seller's attorneys feel they can get around any legal claims by using the disclaimer that the tuning kits are for "off road use only".

Tuning kit sellers also point out how easily the kits are removed. However, as each year goes by, we don't know what kind of electronic tracking might be built into the Bosch controller. Like " black box" capabilities? This potential recording aside , who in their right mind would take the bike in for warranty work without removing the tuning kit first?

The above notwithstanding, the Bosch system is so reliable that most users will not be needing to use the warranty anyway.
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If its got a motor somebody is going to figure out a way to tweak it for more power. Its been going on for years and years. The big problem is not the machine but the operator who acts like a knucklehead.
I think you guys are missing a critical point in the article. "However, Bosch is able to track the possible hampering of each individual drive system when logged on for possible malfunctioning of the system." When logged on to what? When you take your bike in for maintenance or tuning?

Now I'm curious if anyone who's modded one has looked for a gps tracker or RFID chip while in the motor/controller.
Lol really...I guess we have a different calibration on 'law breakers'.o_Oo_O
Anyone in the U.K. can use a more powerful e-bike but as well as using all that speed they have to man up to the responsibilities regarding registration, insurance, safety equipment etc. You may be a cell centered hard man who needs the adrenaline rush of tweaking a push bike with an electric motor, me, if I want to go faster I ride my motorbike. It's easy to make fun of legislation but it's there for a reason and it's abuse can affect us all. I hope it's fun in your world, pushing the limits, I'm just glad my life is a bit more meaningful and real. Sad!
Here in the UK you can tune one if you have the licence insurance etc or you use off road. I had an international motorcycle race licence but would still like my bike to go faster than 15mph.
What good reason keeps them at 15mph when I can pedal at over 20?
Maybe with Brexit, this EU regulation will change for the UK, but not by next week. I guess the 15.5 mph limit is designed to give the amount of assist to bring the rider up to the average commuter cyclist. That may work for much of Europe, where the majority of the population are in cities and commuting distances are relitively short. The population in the US is far more spread out and commuting distances are significantly farther, hence the 20 and 28 mph limits. Myself, I'm 11+ miles from milk and bread. I don't think many ebikes would be sold in the US, with a 15.5 mph limit. I don't think I would own one, much less two!
Fortunately I live in the country and no where near a town, I can get to a town off road so unresticting it makes sense. I'm hoping to pick some warranty bits up tomorrow so I will ask to see how they can tell if it's be unrestricted
My biggest challenge with this personally is how it impacts legislation and access. I'm in NY and I have been fighting for years to clarify the laws for Ebikes. Last year we would have passed a law, but NYC wanted NYS to include language to make it a misterminor to tamper with the speed. NYS didn't want to get involved so they decided not to push the bill to a vote this year.

Obviously it's hot enough of a topic for it to come up in the legislation discussion. I don't want to be a downer, but I have recently become aware the possible implications of this and I think most should consider them.

The eMTB thing is a big concern as well and we're beginning to see this in the U.K. and the EU as the market grows. My feeling is companies like Bosch are going to end up shut it down. As the market grows we will see more and more regulations to keep consumers safe. Ultimately I think whatever you decide it's probably a good idea to not speak to speak in forums like this about it.
We've been given several reasons for why the NY state revisions didn't pass. This seems like a legitimate concern for a big city where vendors are using ebikes in somewhat reckless ways.

What role is Bosch playing in all of this? The most popular DIY mid-drive is the BBSHD. Admittedly, it will produce 1500 watts with the highest performance battery. On the other, the motor is locked down to 30 amps (30 X 52v is the max wattage). When a vendor wants to bump up the wattage, they are forced to use a separate controller with the HD, and that is available. But Bafang has locked down the motor at 30 amps. I think this means they could lock it down to 20 amps, or whatever they felt they had to do. About 15 amps would be the 'most legal' with a 60 volt cutoff.

So, Bosch allows dongles or other hacks to increase the power of the motor? The motor and controller architecture is such that it can be tuned against the factory spec, and illegally? How much of this is on Bosch? They can't do what Bafang does, although Bafang is clearly cheating the wattage numbers.

The California labels, covering Max speed, wattage, and Class of bike, kick in a month from now. Bikes come out of California, so they may be Cal configured. I still don't know how they are going to do this, exactly, but once the label is set, it's more of a legal problem if you change the parameters on the label.

@Chris Head was talking about voltage conditioning on one of his bike lines. That works better with watt limits, I guess. It will be dealers and manufacturers of ebikes that will have to comply. But can't they force the manufacturers to make controllers that are locked down? Doesn't Bosch play both sides of the street, not locking their stuff down.
I feel that Bosch is working to limit their liability on this issue. It's a challenge because I'm sure they don't want to redesign their whole system to prevent this. I think we're going to see more on this topic soon.
The dongles just double your cut off limit, they don't change anything with the motor. So, instead of PAS kicking out at 20mph, it would be 40, meaning you can get assist all the time.
Given how many people are using dongles, it is just a matter of time before Bosch and their competitors add a GPS chip to controller.
It's been an issue for years, has anyone heard a peep from any of the manufacturers? I don't think they care.
Kind of like Detroit didn't care when people took their cars and trucks and after marketed them silly? Every car sold just about is able to break any legal speed limit

It voids the manufacturers warranty to add a dongle which is their out. They are not liable so why should they care?
If only, @JRA! Legal liability is a slippery slope when someone is injured riding a modified ebike. Companies or dealers can say that they have no liability if an owner modifies a bike but it doesn't really work that way in reality. Just having a written statement by a manufacturer doesn't prevent a lawsuit by an owner. They all will still have to deal with the attorneys & courts and the cost isn't all from the bills, it's also from the negative publicity.