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Battery sizes and odd electrical gremlins

Discussion in 'Norton Motorcycles (Modern)' started by iwilson, Nov 10, 2019.

  1. iwilson

    iwilson VIP MEMBER

    Nov 6, 2015
    Out for a ride a few weeks ago. Noticed that the Speedo had stopped working and the voltage display was 11.5v. Figured must be the battery on the way out so purchased the factory spec size a 14-BS. Noticed that the dealer had fitted a 9-BS a much smaller battery (90cca vs. 200cca).

    But upon fitting it I noticed two things, firstly the factory spec. size means the positive terminal touches the ali tank of the Domi (saved only by the rubber cap over the terminal) - this is why the dealer had fitted a much smaller battery. So I went and bought the in between size a 12-BS (150cca). So all good except that wasn't the problem! So I've now got three batteries! Scott/Voodooo/other owners with an ali tank what size battery do you run in your bikes?

    For ref. here's the difference in size.


    The bike was starting fine, but whenever I turned the ignition on the voltage display would start to drop down to around 11.5v, despite a brand new fully charged battery installed. So either a fault with the voltage sensor in the instrument cluster or a problem in the wiring loom.

    Started metering the loom and discovered the 30amp fuse holder near the battery had some carbon scoring on it and wasn't sitting tightly in the fuse holder. So cleaned it up and squeezed the connector to get a better grip on the fuse. Noticed that the voltage drop wasn't quite so much, so continued on.


    Never found a smoking gun, but cleaned connectors and applied a bit of dielectric grease as I went. Ended up inside the headlamp assembly. Where I noticed a bit of surface corrosion getting underway - so if you haven't looked it might be an idea to remove and treat before it becomes serious.


    This is after I'd cleaned it up - it looked a lot worse to start with!


    By the time I'd finished the voltage display on the instrument cluster matched what I was seeing at the battery. But just to be sure I took the opportunity to fit a CTEK battery sense to the terminals. This only draws 1mA and displays the battery condition via bluetooth to your phone.


    So clearly worth while occasionally pulling connectors apart, cleaning and applying a smear of dielectric grease.

    One last observation that someone might be able to explain. I notice when I have my charger connected the speedo needle will often rhythmically 'tick' as the battery is being charged. Doesn't do it throughout the charging process but it has something to do with the charger being on. Anyone else notice the same thing? Using a CTEK mxs 5.0 charger on motorbike and AGM mode.

    Last edited: Nov 10, 2019
  2. TonyA


    Jan 16, 2015
    I have not seen this ticking before now. Some type of charging cycle with the CTEK ?
  3. speirmoor

    speirmoor VIP MEMBER

    Apr 11, 2010
    I switched to a Shorai. Much smaller so no touching issues. Also my tank came with insulation on the battery area just in case.
    My Tach would do something similar when charging. I was also having excessive battery drain when bike was switched off. I emailed Norton about it and they said there was some clocks that gave trouble. They sent me a troubleshooting bulletin and I found my Tach was did not comply with their recommendations so they sent me a new one. Cured clock "ticking" but I'm not 100% certain it cured a parasitic drain.
    MxMartin likes this.
  4. iwilson

    iwilson VIP MEMBER

    Nov 6, 2015
    The dealer put insulation on my tank as well. But... over time with the vibration etc, it's not hard to imagine it wearing through and with no fuse to blow the battery would quickly burn through the tank and I don't need to tell you what would happen next!

    Could you send me the bulletin on the ticking please, mine is the speedometer not the tacho, but it might be useful to understand what's going on.
    Last edited: Nov 11, 2019 at 3:57 PM
  5. MxMartin


    Nov 13, 2017
    I had parasitic drain but my clocks didn't 'tick'. Norton traced my current draw to a faulty speedo and replaced it, battery drain when not on charge is much better.

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