changing sevcon behaviour

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flippy   100 kW

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changing sevcon behaviour

Post by flippy » Jul 19 2018 10:01am

govecs put a gen4 size 4 in all their scooters and they all seem to have the VERY annoying habit of "hunting" at the top speed.

this means the max rpm fluctuates slighty constantly despite being under constant load.
i am looking at DVT but i have trouble changing the right settings to stop this behaviour.

does anyone have any bright ideas on how to stabilize the top speed?
Lithium beats liquid dinosaurs.

Cnutsol   1 µW

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Joined: Jun 26 2014 3:00pm

Re: changing sevcon behaviour

Post by Cnutsol » Feb 26 2019 3:56pm

change the front sprocket 13 teeth to a 16 teeth
and with the dvt software reduce the number of max rpm and change the speed radtio odo and trip.
this help enormously in rocking on topspeed
the new Govecs 1.5 2.5 2.6 already have a 16 tands sprocket

Cnutsol

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flippy   100 kW

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Re: changing sevcon behaviour

Post by flippy » Feb 26 2019 4:11pm

i understand that and i am desperatly looking at finding a bigger sprocket but even if i could find one for sale i still cant i mount it because the axle is different. it would require a custom made sprocket.

i already have upgraded the motor to a lektrika and "downgraded" the controller to a size 2 (the bigger storage is really nice and a size 2 is still way too much).
that did help a bit but that is possibly because i increased the top speed as well (3800rpm/53kph and 4500rkm/63kph respectivly) and already set the regen WAY up so it actually usable, i get 1.5kW of regen now. no need to use the brake anymore.
it does still hunt a bit but its already a lot better then with the italvel motor wich was basically destroying itself at 45+kph.

if you know where i can get a 16 teeth that fits a lektrika then i am all ears.
it would also be nice if it does not chews up belts anymore with the bigger sprocket.

i am seriously considering getting a e-max and trying that out, i am pretty much sold on the fact that hub drive is vastly superior to belt/chain drive.
Lithium beats liquid dinosaurs.

Cnutsol   1 µW

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Re: changing sevcon behaviour

Post by Cnutsol » Mar 07 2019 4:47pm

You can order a front sprocket 13 16 or 18 @ importers its fits the lectrika motor.
https://www.govecsgroup.com/importeure/

if you use the lectrika motor and size 2 sevon did you also replace the .dld file ??

Govecs has developed a duo belt drive for 45 speed and higher they call it "dirth"
hub-moters are old tech.
With belt drive, the motor can deliver much more torh during acceleration and lowers the amp's of the battery. The Vespa Elektrica itself has a metal gearbox. The Emax ,Vectrix VX-2 and Govecs are similar in design my opinion the govecs has the better technique

I have updated my Govecs Go s1.2 year 2012 with sevon size2 lektrika moter new front fork an back spring and blue display next step is to replace the battery for a BMZ battery with canbus 72v 32Ah and a blue tooth dongle
https://www.hsct.nl/winkel/speedapp-ev-for-sevcon/ :D

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flippy   100 kW

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Joined: Aug 12 2015 3:07pm

Re: changing sevcon behaviour

Post by flippy » Mar 07 2019 6:15pm

Helmstad has been quite "unhelpful" in the past with these matters.

i have all the original govecs files for all the motors. so i can put in any motor on any controller i want. but i got the letrika with the controller (and a spare frame :mrgreen: )
Lithium beats liquid dinosaurs.

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