Quote from: AldobaroniSocal on December 16, 2025, 12:50:18 AMHi everyone, hoping to get some advice from anyone who's dealt with this before.

I recently picked up a RadRover 6+ used and it's throwing Error 21 on startup. The display boots normally through the RAD sequence, then once it hits the speed screen it flips to an oscillating 21. The bike will not assist.

Here's what I've already tested to rule things out:
I unplugged the tail light and the error stayed.
I unplugged both brake cutoff switches and the error stayed.
I swapped in a known good display from another working RadRover 6+ and the error stayed.

One brake-related issue I still have is that only the right brake lever activates the rear brake light. The left lever does not, even though the front brake itself works mechanically. The rear brake is weak and likely needs a bleed, but I understand the hydraulic issue is separate from the electrical brake cutoff.

At this point I'm trying to determine if this is a controller issue, wiring harness issue, or something less common like the motor. I do have another working RR6+ and I'm planning to try swapping components to isolate the fault.

If anyone has had Error 21 persist after ruling out the display, brake switches, and tail light, I'd really appreciate hearing what the actual fix ended up being.

Thanks in advance for any insight. I'm trying to avoid throwing parts at it if possible.

Did you ever solve the error 21 problem?

So I'm just wondering, what happened to peanutbutterpope and the "Double your battery life" thread. It was started by DickB who made a device and then peanutbutterpope was going to take over the production... and then the thread died out.

Double your battery life

Anyone know what happened to that project? I'd be interested in buying one or something similar.

Thanks
MikeC

That fixed it. Thanks for that and all the knowledge sharing you do.

Any update on the problem and solution?
Thanks

It could be me, or my cellphone, because we're camping in hinterlands. But the link doesn't work for me. The Google drive message says it's in the trash, and details about the file say the public can't download it...

Any more takers? He can't start until he gets a few more takers.

Thanks
Mike

Quote from: DickB on September 09, 2021, 09:12:13 AM
If you want a diode device, send a message with your email address. I will send you a PayPal invoice. You can pay with a PayPal account or credit card.

Hi Dick, PM has been sent.
Mike

Quote from: DickB on September 04, 2021, 05:03:56 AM
I will be making up a batch. It will be a couple of weeks for me to order parts and build. When I work out how to take orders and payment, I will post here.

Just a thought. Chase bank, so I assume others too, use a service called Zelle/sp. If you set it up in your bank's app, people can send you money by sending it to your cellphone number, which you include when you setup your account. Maybe you can PM with interested buyers to provide your cellphone number rather than post it here in the public forum.

By the way, I'll take one.

Quote from: DickB on August 11, 2021, 04:50:06 AM
The parts are relatively inexpensive, but I got parts from multiple sources, so shipping costs can add up. I'd consider making a small batch if there is sufficient interest.

I can solder, but it ain't pretty. If you're keeping a tally, I'd buy two (one for both myself and my wife).
Mike