increasing 250 watt Radwagon 4 to 350 watt

[Dara]

Hello all,

I have recently bought a radwagon 4 in France limited to 250 watts. With 2 kids and an uphill climb to school the bike suffers a bit and me too. I was wondering if I can change the settings to get a bit more torque like 350 watts.

Few more things,

** I've lost throttle response time (and sometimes no response) which is a big problem when I have to pedal after red light turns to green carrying two kids. I'm stuck in the middle of the intersection.
** Secondly does anyone know what "speed" is means when we go into the settings, there are different levels 1,2,3..
** I'm going to install hydraulic brakes but won't have the motor cutoff system. Will that be a problem?

Huge thanks for your time. Hope some you experienced rad owners can help me out.

Best Regards.... Dara

[John Rose]

Limiting the power seems dumb, if the object is actually to limit the speed, especially for a bike that is purpose-built to carry more than just a single rider. 

** I'm going to install hydraulic brakes but won't have the motor cutoff system. Will that be a problem?

It could be, from a legal standpoint.
Some jurisdictions require an automatic motor cutoff when you stop pedalling and/or either of the brakes are applied.

In addition, from https://www.businesscoot.com/en/study/the-electric-bicycle-market-france :

[UPDATE: 12/10/2023]
Current regulations
All electric vehicles, including EABs, must be certified.
Whether in France, Belgium or Switzerland, it's important to have homologation certification to be able to drive. Generally speaking, it's the seller who has to provide this document. Alternatively, you can contact an organization such as LNE, UTAC or CRITT, whose homologation certificate ...

And 'homologations" means:

Homologation is the granting of approval by an official authority. This may be a court of law, a government department, or an academic or professional body, any of which would normally work from a set of rules or standards to determine whether such approval should be given.

So, any mods like the one(s) you're considering would mean that it's no longer a homologated product.

I am unable to locate the actual laws (on a government site, not some cycling club web site) concerning the detailed technical requirements for ebikes in France. That's what you want to find, since that's what the police will go by if you get pulled over.

As far as the throttle is concerned, I was under the impression that in the EU (maybe it's just in the UK?) you could have a throttle that is limited to some short length of time, like for getting through an intersection after a stop light.
But you sound like you have a faulty and/or intermittent throttle, is that it?

If you have a cadence sensor (which the North American RadWagons have), and you are at maximum pedal assist, then once you turn the pedal crank a half turn or so it should be the same as giving it full throttle. On my RadMini ST2 for instance, the displayed power peaks at 500 W whether it's pedalling with PAS 5, or fully twisting the throttle. In either case, the controller ramps up the power so that it doesn't send you flying over the rear fender. (That's what I'm given to believe at any rate, and that it's not just inertia.)
So that's, what, 1 or 2 seconds delay?

[Dara]

Thank you for your reply. About the power I want to increase from 250 watts to 350 watts, not to decrease. I will consider more seriously the legal aspects in my attempts to improve things. Regards

[Ddaybc]

On my Canadian RW4 I can use the throttle even when I'm on "0" pedal assist. However I've seen some EU reviews indicating, for some brands, the throttle doesn't work if pedal assist is set at "0". John Rose is correct about the motor taking it's cue from the cadence sensor so it may take some time to kick in. Mine kicks in at about 1/4 turn but many have said it takes 1/2 turn of the pedals.
In the EU I also believe the maximum speed is limited by what pedal assist level you have the bike set at. Is that correct? On my RW4 the full throttle and speed may be accessed regardless.
Perhaps look into the Eggrider controller system. It will unlock your bike to obtain what you are looking for and it's made in the EU.

[handlebar]

https://www.youtube.com/watch?v=3k_Y-cgNKKQ
A couple of years ago, Ryan, who runs the forum, put an upgraded controller on his Radwagon 4.

I put upgrades on two Radpower bikes because they weren't giving me the rated motor output. They also offer more user settings, such as whether I can start with throttle only and how briskly the throttle will give a stopped bike power.

If your hydraulic brake levers were made for ebikes, I think they must have places to insert cutoff switches if the switches aren't included.

[inoxa]

Here is an option so that you don't have to put new brake levers on your bike and still upgrade to hydraulic. 

https://amzn.to/3u369nd

[John Rose]

... I put upgrades on two Radpower bikes because they weren't giving me the rated motor output. They also offer more user settings, such as whether I can start with throttle only and how briskly the throttle will give a stopped bike power. ...

Hmmm. Maybe Rad has changed that since then because on our unmodded RadMini ST2 (2020?) and RadExpand 5 I can get going from a stop on throttle only.
I can use short bursts of the throttle instead of the (too-speedy) Walk Mode when I take them up the short ramp out the basement door.

[handlebar]

Both my Rads had throttle always available. With two other brands, you have to have PAS 1 or higher to have throttle available. With my aftermarket controllers, I could set it either way or other ways. (The settings manual is 40 pages.)

With the aftermarket controllers, I can set how fast the throttle gives me power from a stop. With the stock Rads, it built a little slowly. That's what I would want if I were using the throttle to walk a bike up a ramp.

[JimInPT]

Here is an option so that you don't have to put new brake levers on your bike and still upgrade to hydraulic. 

https://amzn.to/3u369nd

I can vouch for those, which I bought through Area 13 at a better price, but that was over a year ago.  I'm very happy with the slight but noticeable increase in braking power, less need for adjustments and the fact that the pistons push from both sides instead of just one like the factory calipers, so they don't distort the rotors.

[Dara]

The Juin Tech hydraulic/cable brake system is a great idea. Didn't know this system existed. Will definitely look into it after I return my recent purchase of replacement hydraulic brakes. Thank you very much