Preemptive strike.

[pa_broon74]

Hey folks.

While this is isn't a problem yet, I reckon that its going to become one pretty soon so I thought I'd ask now. I have a Honda CLR 125, good bike no problems (other than the usual battery here and spark plug there.)

Over the past 4 or 5 days I've noticed that when its idling all the lights flicker, it never used to do this. This morning, it was slow in starting, it did (as it normally does) but the starter motor chuffed and strained.

The battery is only 6 months old as is the plug. I was just wondering what could be on its way out, what the next most common thing is. I'm thinking maybe the ignition coil or something in the loop that recharges the battery... (Feel free to explain this, I've never had reason to examine this area closely

As I said, its not urgent yet. But you know how it is, you get tuned into the noises your bike makes and when it starts squeeking or chuffing you think: Uh oh!

Thanks in advance.

[stinkwheel]

Well check the battery terminals are tight and corrosion free. Give the switches a scoosh of WD40, check the bulb holders are corrosion free, make sure the battery electrolyte is topped up.

If you have a voltmeter, measure the voltage across the battery terminals. It should be sitting at about 12v at rest. As the engine is revved up, the voltage should rise to about 14v. This indicates the battery is being charged. Anything below 10v at rest or 13v when revving is cause for concern, 15v or higher is also a worry.

Obviously, if it has a 6v charging system then 6v at rest and 7.5v when revved would be the norm.

If you don't have a voltmeter, maybe you could borrow one. Failing that you can buy a cheap multimeter for about a fiver, it's a tool you only use occasionally but when needed it is damned useful.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[pa_broon74]

I have a voltmeter, haven't used it in a while but it should still work... I'll check it out tonight, thanks.

Assuming the battery isn't charging, or atleast not properly, would that mean a new alternator? I have no idea how this goes down on a bike. I wouldn't even know where the alterator is on a bike, I've never looked.

Used to mess with cars alot but I've never needed to look at a bike before.

Ta.

[stinkwheel]

I'm not entirely certain about your bike. Most bikes have a seperate regulator rectifier unit (it's built in to a car alternator), which would be the most likely suspect if the battery isn't charging properly.

Some small hondas have a different arrangement though, more like a dynamo. I could tell you if I had a circuit diagram in front of me.

The alternator windings can be tested using a multimeter too but as I said, I'm not familiar with your bike so I don't know what sort of charging setup it has.

If it's not charging properly, have a scout about for a 'black box' which may have cooling vanes on and would have six wires leading into it. On a Honda there would be three yellows, a red, a green and a black. The red wire would usually lead to the battery positive or the main fuse.

If you find something looking like that, the bike has a conventional, three phase charging system because you've just found the regulator/rectifier.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[pa_broon74]

[stinkwheel]

Well, you can test your alternator windings easily enough then.

Undo the connector block from the reg/rec and set your multimeter to measure resistance. Test the following:

Any pair of yellows should have the same resistance (these are your alternator windings).

Any yellow to earth (bare metal on the frame or battery negative) should have an open circuit (infinity resistance).

Green to battery negative should have nearly zero resistance.

There should be battery voltage on the red wire at all times.

There should be battery voltage on the black wire only when the ignition is switched on.

If all this checks out, it is highly unlikely that there is anything wrong with the alternator or the wiring in the charging system. (Possible still, but unlikely).

It's very difficult to test the reg/rec itself. If it isn't charging properly and everything else checks out ok, suspect the reg/rec.

It's also worth going through and checking terminals for corrosion/looseness and giving any frame earths a clean up.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Gazdaman]

Could be that your idle is very low..

I assume the lights don't flicker if you rev it slightly. Could be it's idling low enough to just about run, but hardly get any juice flowing.

Gaz

[pa_broon74]

Yeah.

I kinda thought that, but I haven't fiddled with anything, (normally if I 'fiddle' with something there are negative repercussions of some sort.)

It just started doing it. It sounds the same, I know it needs some oil, I have a small leak on one of the gaskets. I'll top it up this afternoon assuming it starts and I get it home, heh!

TBH, it really needs a proper service, so far I've done it myself (which for the afore-mentioned reason doesn't fill me with confidence )

Cheers

[pa_broon74]

Had to dig this up.

That flickering light thing has become a problem, I was leaving the gym earlier and while smoking a fag (lifes a balance) I noticed the rear light was flickering really badly. It was almost as if the break light (same bulb) was coming on and off really quickly int ime with the revs at idle.

Anyway, I keep some tools under the seat and they tend to slide about and in the past, have shorted the battery out. I took them all out but its still doing the flickering thing and sometimes it just doesn't turn over at all, just clicks.

I know how the electrical system in a car works with regards to starting and charging etc but not on a bike, I've just never had to look at it. Can some one explain to me how the it work? Just an idiots guide to the ignition process so I can figure out what I need to replace.

Its a honda CLR125, the battery & plug is only 4 months old so I'm assuming its not that. Only other thing to note, sometimes when starting from cold it chuffs, like the battery is slightly flat

Anyway, any advice/help would be hugely appreciated. I'm skint (due to upcoming lessons/test) so would prefer to fix this myself.

Thanks in advance.

[Vincent]

What make was the new battery that you bought 6 months ago. Some of the cheaper ones are very poor quality.

[Gazdaman]

And are your journeys very short? Do you ride with your lights on all the time.

Does just sound like a flat battery, just gotta work out why. Some cheap batteries are pretty shite.

Could be a corroded connector.

Gaz

[pa_broon74]

Mmm...

It was a cheap battery, pretty generic. Cost about £30. I think something is faulty though, sometimes it just doesn't start. You press the go button and it gives a wee click (sounds like a solenoid or reed switch clicking...) but it doesn't turn over.

All I do at this point is lift the seat up, waggle and poke at stuff then it usually works. Its hard to explain precisely what it is that I think is faulty, its a grey box (small, about an inch and a half square) with two 20A fuses attached. Its this thats clicking when it refuses to start.

Add to that; the lights are flickering and quite dim and sometimes the indicators don't flash, the light on the 'dash board' (heh!) just comes on really dim.

If it was a car, I'd say that the alternator was faulty and only charging the battery intermitently. That said, it runs well enough (although its sounding a little rough but i think thats because I over-filled it with oil )

Anyway, I think I'll need to stick it in for a proper service, as I said before; when I "fix" things on it I usually cause another thing to go wrong.

Thanks for the info.

[stinkwheel]

It's got a 3-phase alternator. So three lots of windings with magnets spinning round them which generates AC.

These three phases are passed into a solid state rectifier (a seperate unit) that converts it to DC, the rectifier also contains a voltage regulator based on a zennor diode which regulates the voltage to about 14V. The regulator/rectifier then plugs straight into the battery.

The alternator windings are located under the left crankcase cover, they may or may not be sat in oil.

The starter circuit is like a car. The starter button operates a solenoid which in turn feeds power to the starter motor. Sometimes goes via a relay in the fusebox.

Here's a link to an excelent article about motorcycle wiring:
https://www.btinternet.com/~jhpart/bkwirec.htm
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.