What is top speed potential of my mobility scooter with reprogramming?

[YellowBuzzaroundEX]

Hello! My name is Charley.

I live in USA and own a mobility scooter that in USA is called a Golden Buzzaround EX.
In UK that scooter is called a TGA Zest Plus.
It has a Dynamic 90A Type R controller.
It has two 12V 35AH (in series) Powersonic PDC lead acid AGM U1 batteries. So a 24V system using AGM batteries.

I weigh 150 lbs (68 KG).
I am physically handicapped and use my mobility scooter for mobility and transportation.
My profession is computer IT software support and software engineer.

I've never programmed a scooter before. This will be a new experience for me. I'm learning as I go.

Today I ordered a Dynamic brand DWIZ-KIT and OEM-U dongle from a scooter store in Taiwan that I found online. I think this is what I need to reprogram the scooter's controller.

What is top speed potential of my scooter by altering it's program with no physical modifications?

 

[Chalo]

You haven't furnished enough data to make an estimate, and the manufacturer specs for that scooter don't either.

To make an informed estimate of top speed, you should know
- how much maximum current your controller can deliver
- what the steady battery voltage is at that current
- what is your motor's RPM per volt
- what is the overall gear ratio between motor and wheel, and
- what is the drive wheel diameter.

 

[YellowBuzzaroundEX]

Tire Diameter 10"
320W Motor
Motor RPM pee volt. I have no clue.
90A Controller
   Continuous Current 14A
   Peak Current 40A for <60 sec
   Boost Current 10A
   Booster Current 90A
   Boost Time 8 seconds

I just want to increase speed 1 mph (from 6 to 7 mph). Surely that small increase wouldn't harm the batteries or motor?

 

[AussieRider]

The top speed of mobility scooters is set mainly by the final drive ratio.
Only way to change that is a new transaxle or bigger diameter wheels / tyres
When you get your cables, OEM dongle & software set up, you'll probably find that the maximum forward speed parameter is already set to 100%. Most scooters with the Dynamic R series D90 controller are. You can up the acceleration, but at the expense of the batteries, both in range and overall cycle life.
Have fun.

AussieRider

 

[E-HP]

Tire Diameter 10"
320W Motor
Motor RPM pee volt. I have no clue.
90A Controller
   Continuous Current 14A
   Peak Current 40A for <60 sec
   Boost Current 10A
   Booster Current 90A
   Boost Time 8 seconds

I just want to increase speed 1 mph (from 6 to 7 mph). Surely that small increase wouldn't harm the batteries or motor?

At those speeds, the KV of the motor (or voltage) is the limiting factor for speed. So, the motor isn't going to spin any faster unless it's provided higher voltage, so you'd need to change the gearing for more speed. At higher speed, wind and rolling resistance would be a greater factor, so more power could yield some gains, but that's not the case here.

How are you measuring the speed? If there's actually a speedometer, you could test to see if the controller is imposing a speed limit by checking the wheel speed with the wheel elevated (no load) and the speed when riding, and if both are the same, then the controller could have a speed limit imposed in the software (or hardware, if there is a jumper). If that were the case, then you may be able to remove that limit, but can't tell without more information.

Since you already ordered the interface, no need to guess. You can play around with the settings and see what happens. Good luck.

 

[YellowBuzzaroundEX]

I use a GPS Speedometer app on my phone to measure speed.

I already increased speed from 5 to 6 mph by increasing tire diameter 1" taller than stock.

Although I have not received my Dynamic DWIZ programming kit yet, I did download it's user manual and read it. I also downloaded and read the user manual for my scooter's controller.

Controller user manual says the max speed limitation parameter can be set to anywhere from 10% to 100%. It says 60% is the default. So it might be possible to increase the controller's max speed parameter, but I don't know if my batteries and motor are up to it.

I guess I'll just try it and see what happens. The scooter is rated for up to 325 lbs person and I weigh only 150 lbs. So it seems to me unlikely that I will damage anything from attempting to increase speed 1 mph.

 

[YellowBuzzaroundEX]

I downloaded and read the controller's user manual (but my DWIZ kit has not yet arrived by mail).

There's adjustable parameters for:

Maximum Forward Speed, which can be set from 10% to 100%. Default is 60%.

Maximum Motor Voltage, which can be set from 2V to 40.2V. Default is 28.8V.

The manual contains the following note about the Max Motor Voltage setting:

"Note: If local regulations require scooter speed be limited to a specific value, use Max Motor Voltage parameter to set a speed limit for a particular scooter type (for specific motor and wheel diameter)."

Might I use one or both of those controller parameters to increase speed 1 mph?

Technically I mean one additional mph. I already increased tire diameter 1" to get from 5 to 6 mph. Now I'm hoping to alter programmer parameters to get from 6 to 7 mph.

 

[YellowBuzzaroundEX]

My DWIZ controller programming kit has not yet arrived by mail, but trying to get a headstart on knowledge, I downloaded and read the user manuals for my controller and DWIZ-KIT.

I got the controller parameters info (mentioned in my prior post) from the user manual for my controller. I read the manual hoping to learn some possibilities.

Until my DWIZ-KIT arrives, I can't yet know what my scooter controller's settings currently are.

 

[Chalo]

If you have any way of determining your wheel RPM (optical tachometer, or comparing against a beats per minute audio track), then you could block up the scooter and juice the motor directly from a 12V battery. From that plus a measurement of battery volts while running, you could calculate the wheel RPM per volt. That would help a great deal.

 

[YellowBuzzaroundEX]

Since I already ordered the Dynamic DWIZ-KIT and OEM-U dongle, I think the easiest way to find out if my scooter can go faster is to change the parameters for forward speed and max voltage allowed (if they can be increased). Then I'll drive it and look at my GPS Speedometer.

 

[AussieRider]

G'day Charley.
When you get your D-wiz kit first thing to do is, once you have the config loaded, is to save it in case you mess up.
Don't ask how I know!
Yes, the controller manual may say the default maximum speed is 60% but that's the factory default. Then the scooter manufacturers load their own configs.

AussieRider

 

[YellowBuzzaroundEX]

G'day Charley.
When you get your D-wiz kit first thing to do is, once you have the config loaded, is to save it in case you mess up.
Don't ask how I know!
Yes, the controller manual may say the default maximum speed is 60% but that's the factory default. Then the scooter manufacturers load their own configs.

I saved a backup of settings-parameters to my desktop computer hard drive before changing the settings-parameters in scooter controller.

 

[YellowBuzzaroundEX]

I improved max acceleration parameter's performance from sluggish to excessive. Now it feels like I was launched from a catapalt. It's now to much acceleration for comfort.

Next I'll going to try a max acceleration setting somewhere around medium acceleration.

I increased top speed by 0.5 mph by removing max speed limitation. It's now as much rpm as I can get with a 24V lead battery system.

However, I gained an additional 1 mph speed by installing 1" taller tires. To accomplish this on front wheel (of my 3 wheel scooter) my cousin installed a different steering headtube/fork from my larger model of mobility scooter of same brand. The new steering headtube and its bearings are same size, but the fork is larger and accommodates a taller tire.

Increasing diameter of rear wheels was easier. He removed wheel/tires from my large scooter and installed on my small scooter. He used an angle grinder to make a little more clearance for the 1" taller tires (which are also 0.5" wider tires).

My small scooter originally went 4 mph. It now goes 6.5 mph. That's fast enough for a small, portable travel-boot scooter.

My larger scooter originally went 5 mph. It will go 6.5 mph when we're done.

That's the limit of what we can accomplish with these scooters and their stock 24V systems. If we still wanted more speed, we'd need to step up to 36V, but it's not worth the effort to me.

 

[AussieRider]

Hi there Yellow.
Somewhere on the transaxle you should find a label with the drive ratio eg: 22:1. If you can find a transaxle from an old scooter with a taller ratio, say 18:1 you'll get a higher top speed. I've seen ratios up to 13:1 but gave the scooter roughly double the legal top speed of 10km/h here in Aus.

AussieRider