Tuesday, 17 September 2013

Honda Beat EV takes its first drive

Saturday 14th September, got stuck into the car early on Saturday morning as Steve was planning to visit and give me a hand getting the car going, removed the throttle position assembly and took it indoors to do a full breakdown and check (on Steves advice) I can believe I did not do this initially but I guess I thought there was not much that could be done wrong here.

How wrong was I, after emailing Steve last week he had advised I took the TPS assembly out and diagnosed it on the bench to make sure It was putting out a clean 0-5V signal from zero throttle position to 5V max throttle position, plus I had a sneaky feeling that I may have put the magnets in wrong (when I got the TPS assembly from Steve it had no magnets or sensor fitted).

Spent half an hour or so re-soldering the sensor to the throttle cable to allow for better insulation of each TPS sensor wire, it’s a very small sensor, and the hole it fits into is not much larger either so it leaves very little space to insulate everything.

Wired it up to my bench PSU and gave it 5V monitored output signal and waved the sensor at the magnets, nothing not a dickybird!

I was beginning to wonder if the TPS was stuffed when I discovered that the hall effect sensor only works when it is in close proximity to the magnets so I fitted the sensor in its housing and screwed this into the TPS assembly and voila I had needle movement on my DVM, spent the next 30 minutes discovering that I had the magnets 90 degrees out of phase and one set reverse orientated, corrected all of this and I had a good signal coming out of the TPS, Time to put it back in the car.

Refitted the TPS assembly and fired up the Soliton for a recalibration of the throttle, there was no apparent change until I touched the throttle after recalibrating and heard the pleasing sound of the Kostov whirring into life

WICKED, IT WORKS! “Quick love get the camera” I shouted to my partner and here is the result.


  1. Hello. I'm doing a conversion, help me giving me the list of materials that you used. Motor, controller and components that you consider necessary and special. Have electrical plans or something? If you want to help, send me an email to admdq@hotmail.com
    Thank you!

    1. Hi Gabriel

      Great to hear you are converting your own EV, do you have a blog?

      All of the detail is in my blog on what parts I used but it would take a while to find it all so here goes.

      I used a Kostov K9 HV (220V) Motor, Soliton Jr controller from evenetics, 108 x LIPO 5S batteries with LVC/HVC cut-off boards from Jozztek.co.uk (I also bought my batteries from Steve), and I am building the 12kw charger from EMW.

      That is all the basic bits plus:-

      Several meters of welders cable
      A PSU to act as an alternator equivalent (a cheaper alternative to a DC-DC convertor but it needs 220v to work)
      3 automotive relays - 1 for PSU cut-off - 1 for vacuum pump cut-off and the other 1 to protect the Vacuum sensor (found this out the hard way! blew my first sensor)
      Plenty of automotive signal wire
      A 12V 35AH block of LIFEPO to act as the 12V battery
      A Large Cycle annalist to be used as a fuel gauge equivalent (not yet fitted)
      £500 worth of LVC/HVC cut-off circuit boards fitted inside the battery boxes, vital if you want some battery protection (fitted but not yet wired in)
      Aluminium battery boxes, custom made to the exact size (mm perfect) as the batteries need to be held from expanding at all which they do when being charged/discharged.
      Aluminium Charger box custom made again (got this made along with the batt boxes.
      A good mechanic friend (this is vital unless you are a mechanic yourself and can weld steel and fabricate motor mounts etc.
      A good EV specialist friend, If I were you I would spend a while on the forums (diyelectriccar is the best IMO) and find someone in your area that has already built an EV and get to know them, this is also vital as unless you are a HV electrical specialist you will need lots of advice, I am happy to help via email but having someone close you can talk to is very handy.

      all in all my conversion has cost me around 12K GBP and taken almost exactly 1 year to complete.