Showing posts with label Gammatronix. Show all posts
Showing posts with label Gammatronix. Show all posts

Tuesday, 14 April 2026

SQ4 - batteries

  For the record, let it be known that I have today fitted a second battery to the system on the Square Four. This returns it to the layout that we ran for the first 7 years or so of its time in service. We now have 19 amp hours of capacity extended from the 12 amp hours we've been running for the last year.

We are back to running these VRLA batteries again: 

A few miles run later in the day showed one-kick starting, there is no fuel leak and the idle is fine. The ammeter showed a charge; the battery monitor also showed a charge and did not go out of the green zone. Since most of the run was quite slow, perhaps I should not be surprised that the battery charger spent a little time returning the batteries to full charge at the end of the day?

Tuesday, 7 April 2026

SQ4 - a little investigation

 Of course, a broken motorcycle can’t be left for too long, especially when your daily rider has been persuaded from your grasp.

There were a few problems to investigate, possibly associated:

  • There was a carburetter leak, or possibly flooding 
  • The battery indicator was showing far too much red, considering the 60 miles the bike traveled yesterday 
  • The bike refused to start twice yesterday, needing pushing to the top of a hill and roll-starting 

Putting the CTEK on the battery had it charging normally, but it was very flat:


But why so flat? According to the ammeter, the battery does charge and indeed, it was charging on the way home. I did notice the ignition had been left on as Tom had complained the engine wouldn’t idle and it had died when he arrived. I currently believe this has more to do with the battery than anything else.

There is no leakage from the battery with the engine not running and you can measure normal currents with lights on, though with the LEDs fitted to this bike these are minimal. The ignition circuit draws 400 mA without the engine running - I think it would be a good idea to try this with the engine running.

I've also realised that the red spot ammeter doesn't show very much deflection at all - I calibrated the one on the Huntmaster against my bench power supply and there is a lot more movement. I wonder if the Square Four has a 30-0-30 ammeter.

A simple test with a 35 watt bulb revealed that the ammeter appears to be 15-0-15 - while I was doing this test the multimeter was reading 5 amps.


As a first step towards sorting the fuel leak, I removed the drain plug/main jet holder and finding no new fibre washer of the right size, sealed it with a wipe of Threebond 1215. That fixed the leak, and there is no evidence of flooding. 

Amelia started first time like she always does.

As to the idle, I don’t know yet as I haven’t got it warm enough to close the bi-starter.

Monday, 6 April 2026

SQ4 - a ride out

 My son made a surprise visit today to borrow one of my CTEK battery chargers. He's not seen the Huntmaster yet and we agreed that I would ride with him halfway home so that he could have a go on it. He was very pleased with it.

However, when he arrived on Square Four he was complaining that it wouldn't idle. I noticed that he'd left the fuel on and the ignition on, and the battery condition light was showing red. I got it started by bumping it down the hill and rode it to North Walsham; it was okay ish but it obviously wasn't happy at low engine revs - but it was charging.

After a bit of a chat at the North Norfolk Motorcycle Museum, I left to go home but it wouldn't start at all - the carburettor was dripping and the battery condition light was still showing red which suggests the battery is not holding a charge. Again I'd left the fuel on, so maybe it was overflowing and the float valve is not working properly, or maybe there's a leak. 

Eventually I got it started by rolling it downhill and and rode it home like a bat out of hell at up to 60 miles an hour. It was charging, and going fine and I got home safely though the front brake is a lot worse than the one on the Huntmaster. 

I put it on the battery charger when I got home and the battery condition light showed red for several minutes, which is unusual - normally if I put it on charge it will go to green straight away. After a couple of minutes it went to solid green which means it's charging or fully charged.

There's something wrong here.

Monday, 2 November 2020

SQ4 - low batteries and flashing lights

The batteries on the SQ4 are now seven years old and are coming to the end of their life, as witnessed by a complete failure to start earlier this year, remedied with the CTEK charger, and a short trip out a few days ago. This one was odd - I had left it idling on the bi-starter to warm up and all was fine (though of course at that speed it wasn't charging). I then took it out and it had no power, eventually dropping onto three cylinders within a few hundred yards of the house - I travelled 1/2 a mile in all, none of it at high enough speeds to charge the battery.

Getting home, the multimeter showed my batteries were down to 5.5 V or so. New batteries are on the horizon!

In the meantime, picking up on a thread in the AOMCC forum I had bought a battery condition monitor from Gammatronix:

I've chosen to fit it in the top of the dummy battery box. It fits in a 14mm hole which I cut with a cone drill.


I've sealed it with some silicone on the outside:


It's also protected on the inside with some pvc sleeving:


Once you have fitted the battery monitor and have wired it up (even temporarily - it remembers it's settings) you have to programme it. This is by a simple sequence of button pushes. I have it set to 6V, Map #3:


There's a further map #6, which is for low current applications and shows a slow red, yellow or green blink according to voltage level.

Here is a very exciting video of a LED flashing green. Tell your friends, it is riveting stuff: 

Eagle eyed readers will see the CTEK charging connector I have fitted in the background. 

The battery monitor is wired in using a long twin core cable, so that I can remove the dummy battery box lid and lay it on the seat for battery or fuse box access.