My ZIPPER brand e-bike is en15194 compliant so does that mean it's not possible to de-restrict it? I can't figure out how to change speed through the display either. BAH HUMBUG to legitimacy!
In the absence of a 'dongle' or popular utube vid hack, the catch all solution (well most) is a replacement of the control system that contains the compliant programming with a generic model usually that will also provide more amps for torque and speed.
If lucky its a pull and plug in a replacement silverbox and display unit. - Most ebike control systems especially the generic replacements use software in both the control box and the display unit, #1 rule BUY BOTH TOGETHER to avoid communication problems.
Now if your bike can reach and maintain 15 mph ok and the battery lasts long enough for the trips you take, I would think long and hard about about making the mod to your bike.
Bikes with good brakes can handle 15 mph even with a lump like me on em, - start moving at 20mph or more and other road users wont expect you to move that fast and your stopping distance will grow. btw rolling at speed when Not downhill.. without pedalling is a dead give-away..
If its something you NEED to do, dont cheap out on the replacement controller- opt for the forum favourite KT brand. This will allow you to set a default max 15.5 mph top speed. Then if you want to negate that just enter the config and lift it.. Should you get stopped turn off the system (battery switch is probably the quickest way) and it will restart with the default speed cap as it should.. - set a security code for the settings and if asked for it by plod suggest you were never given it..
Not fool-proof nor is it advice, just information..
Depending on where you are in life you could be risking a lot for very little, if involved in a rta your non compliant pedelec would be a blame and liability magnet possibly making you the default cause and footing the bills. and if you have/need a driving licence??
Check out the Seizures thread and how frequently its updated with reports from local press..
imho if you need to move faster than the 15.5 mph pedelec speed cap, get a moped or e-moped.. or pedal faster.