Gavin DPV battery replacement? What Ah?

[PfcAJ]

Sure... Not for awesome guys like yourself sir. *clap clap*

(Btw, See you still hasn't aged much during the last decade or so that i haven't been active in here... lol)

Consistency is key

 

[Gone for diving]

So this is all in all just a voltage regulator that you can adjust on-the-fly right? (or leave at one voltage out? Like 24v, right?)

It is not a voltage regulator...
Input voltage and output voltage is the same. It controls current mainly... under load it will look like the voltage is lower,
But it is really a very fast toggle SW being turned on and off very fast, at different speeds, for variable speed,

Do you have any hands on experience with the Gavin, and this brush board consern? I would like tho hear from someone that acually had this problem, and not just people hearing about others, like i have..

I have no experience with this brush board. It has given zero problems, which means it can handle it.

I am very surprised how little safety are on these old units... no temp sensor or cutouts, battery level etc. Its really flying blind,

Here are a few pictures that I have. Of the gavin we added a battery voltage graph,
But you can get voltmeter that size as well.

 

[tbone1004]

one note about the voltage regulators and what not. One of the ways that we knew the scooters were dying with the lead sleds where when they started slowing down due to the battery voltage dropping which you could feel. On the modern scooters they tend to kick down to a lower gear if they don't have a battery display. You lose both of those if you are using a "dumb" regulator that doesn't give you any warnings. Food for thought.

 

[the_dragon_no1]

It is not a voltage regulator...
Input voltage and output voltage is the same. It controls current mainly... under load it will look like the voltage is lower,
But it is really a very fast toggle SW being turned on and off very fast, at different speeds, for variable speed,

I have no experience with this brush board. It has given zero problems, which means it can handle it.

I am very surprised how little safety are on these old units... no temp sensor or cutouts, battery level etc. Its really flying blind,

Here are a few pictures that I have. Of the gavin we added a battery voltage graph,
But you can get voltmeter that size as well.

Ah ok.

I got this mounted inside the dpv, last owner mounted it. Shows battery voltage/status/history over bluetooth to a phone app. (sorry for the norwegian link) . Kinda wanna see if i can get an external display for this, over bluetooth. Should be possible. Hard casing a phone or something. lol

PROUSER Bluetooth Batteritester

PROUSER IBT1 Batteritester med Bluetooth 6V/12V/24V: IBT1 er en fantastisk nyhet for deg som ønsker kontroll på batteri og ladetilstand Kan kobles til alle typer batterier og gir informasjon om ladespenning, batterispenning og batteristatus direkte på smarttelefon eller nettbrett. Kan kobles...

provolt.no

 

[ofg-1]

Well, I recomment taking the lid off the Gavin, taking out the battery holder, disassembling it, throw it away, go and buy a Blacktip, cut 2 feet off the Gavin tube, attach a long handle, insert a power wire, and turn the Gavin into a really big trolling motor. Would really push a canoe fast.

 

[Whitrzac]

Well, I recomment taking the lid off the Gavin, taking out the battery holder, disassembling it, throw it away, go and buy a Blacktip, cut 2 feet off the Gavin tube, attach a long handle, insert a power wire, and turn the Gavin into a really big trolling motor. Would really push a canoe fast.

I have a black tip, The gavin is probably faster and more reliable....

 

[tbone1004]

I have a black tip, The gavin is probably faster and more reliable....

There is exactly a 0% chance that a Gavin is faster. A Gavin is comparable in speed to a Sierra, but the Blacktip is much faster with about 20% more thrust which is more comparable to the UV-26 which has a faster wind on the motor and brush boards that can handle it.
It's not to say the Gavin isn't "fast enough" but it's not faster.

Reliability is subjective and I wouldn't really say that the Gavin is definitively more reliable as I would argue that the relays are more prone to failing than the ESC's are, as are the AGM batteries. It's a less complex system for sure but I wouldn't go so far as to say it's more reliable.

 

[PfcAJ]

Gavin reliability issues (well, stock ones) always came down to the trigger assembly and prop.

Trigger wire would break or jump off the wheel (the larger wheels are MUCH better), the yoke would break, the blades would wallow out the pitch adjuster, or (weeping and gnashing of teeth) the center screw would back out and jettison your prop into the abyss.

Relays can stick but at least you can still use the scooter. It just sucks.

 

[RTodd]

And Gavin speeds can very dramatically. I had one with a blue tail that no one wanted but was faster than most in the fleet by a large enough margin to make turning it down enough to match speed a chore. Even sounded different. My other one had constant trigger issues as mentioned by AJ.

 

[rjack321]

Gavin reliability issues (well, stock ones) always came down to the trigger assembly and prop.

Trigger wire would break or jump off the wheel (the larger wheels are MUCH better), the yoke would break, the blades would wallow out the pitch adjuster, or (weeping and gnashing of teeth) the center screw would back out and jettison your prop into the abyss.

Relays can stick but at least you can still use the scooter. It just sucks.

Same for me. The relay never caused me issues. The trigger wire itself was fine once I upgraded to the larger wheel after about 2 dives.

The prop was dreadful. I replaced a couple of yokes, and a set of blades. Despite all that the holes on the blades were always sloppy and loose anyway. The hub screw was a continual maintenance issue. It was fine as my second scooter and even an "upgrade" from my Mako. But it's not worth putting $2000 usd worth of lithium batteries in.