Setting the points !!!!!!

[themadatter]

Hello,


Eventually I will have asked every conceivable question to do with honda CG125's ; but I put to practice everything I get from you all !

So,

Setting the points on a CG 125 !
My head gasket is all good now, the top end it tight as a drum and it runs a bit better. 50mph !

I know its still lacking.

I set the points by getting a multimeter and hooking it up to tell me exactly the second the points open.
I then make it so they open at the exact second the flywheel and crankcase marks line up.

So whats all this about gap ?
Surly if I have done it this way I should never need a feeler gauage ?



Any tips ?

thanks !

Jamie

[mr jamez]

Finding the exact point at which they are fully open is the first step, the important part is the gap. When the points are fully open, set the gap with feeler gauges, simple as that.

[themadatter]

Hi there,

How would you be sure you have the point where they are FULLY open ? the gap is so small !

+ surley if you use the multimeter then there is no need for setting gap, becasue you already have in a way...


or am I lost .... ?

Jp

[Simonbt]

Im not sure if your getting confused between setting the gaps and setting the timing. As far as that line on the fly wheel goes you should have sorted that when you were putting the head back on (buy lining the cam up with its corresponding line when you put the chain on). The line on the flywheel shows you when the cam is in the 'dead spot', so neither of the rockers are being pushed and neither of the valves are open. This is when you check the gaps.

Or you are actually talking about something completely different Is it an old CG without electronic ignition?

[themadatter]

hi there !


its old cg with no little black box.

ignition timing is all done by points.

doesn't have a cam either, pushrods !


thanks
jP

[mr jamez]

I have never set the points on a CG or a bike for that matter, but I assume it is similar to that of an older car. Take the dizzy cap off, put the bike in top gear and wheel it forward. You Will see the cam turning, the heel of the points rests on this, when the heel is at the peak of the cam the points are fully open (you could then check to see if you were right with the multimeter). You will find the correct gap in the haynes manual or workshop manual, the gaps are very small for example on my mini it is 0.35mm.

[map]

[stinkwheel]

Folks, you are clouding the issue. It isn't like a car, there is no distributer.

What you have set with your meter is called the static timing. You have gone about this a good way.

Now you will notice that this was adjusted by loosening a couple of screws and rotating the generator backing plate round the axis of the crank until the points open at the correct time. Once that is set you need to set the points gap.

Look at the points, notice how there is a moving part and a stationary part to them. You adjust the points gap by loosening the screw that holds the stationary part of the points to the backing plate and gently nudging it towards or away from the cam using a flat bladed screwdrive in a notch designed for this purpose.

You set this gap when the points are open to their widest distance which you should be able to see from the position of the cam that opens them.

If you want to be ultra accurate with the timing, you need to set it dynamically with the engine running by using a strobe light. Strobes all work differently so ask whoever you borrow it off how to use it.

Anyone know if a CG125 has an ignition auto-advance? If there is one and it is broken, it would certainly rob top-end power.
____________________
“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.

[mchaggis]

Hrm, according to https://www.dansmc.com/IGNITIONTIMING.html, you need to advance the timing as an engine gets older, because with the loss of compression with old rings the combustion happens more slowly.

If you've an old loose engine, perhaps that's a reason for power loss at the top end. Something to think about with my Mum's 11yr old CG.
____________________
I must not be a troll...
Mmmm, Guinness
Discovering the delights of Hammerite and a 3/4" brush.

[themadatter]

Hi all,


Thanks for the replies !

Ok, main problem is that the stator plate is..........static ? so i can't move it.
the only adjustable part is the second screw you mentioned.

The points seat in a small recess which allows them to swing up and down when this bolt is loosened.

So, I can only adjust the gap ? this is why I am confused.

Becasue when I alter one, I alter the other, so if I set the STATIC timing correctly, and then set the gap (if not right after setting timing) I then alter my Static timing !


Do you see what I mean ?

The bike does have an auto ignition advancer, two little weights in springs..

How they work I dont know as the points are driven off a little lobe that sits on the crank and if they are supposed to actually turn this cam them goodluck to them becasue the end of the crank is so rough that the lobe was actually seized on !

I greased it before reassembly last time, but if its supposed to work in the fashion i imagine, then I may need to look at polishing the end of my crank.. ?


Anyway, about the ignition timing !

So any further thoughts would be great !

+ 50 mph does seem slow ! as there is a gear guide on the speedo, and i says 5th gear from 70mph on, and im always one gear behind the guide, which would suggest that the bike is not revving as hard as it should,,,, humm


anyway,
more info would be fantastic !!!!!!!1

thanks, this is really helping me understand !

Jamie

[stinkwheel]

Ok, at this point I should point out that I haven't worked on a CG125 but I have fiddled with several similar small hondas which should be broadly similar, also the way you adjust points is pretty standard.

It is a bit fiddly on hondas because you are having to work through holes in the rotor to get at anything.

Right, so you are looking at your stator plate. Look at where the part of the plate the points are on screws on to the rest of the generator (usually two or three slotted screws). The holes the screws go through should actually be slots. See them?

By loosening these screws you should be able to rotate the plate slightly one way or the other (maybe by about 10 degrees or so). So.

Set the points gap as described before.
Turn the crank so the timing mark is lined up
Rotate the stator plate so the points start to open bang-on the mark.
Check the gap again.
Check the timing again.
Repeat until both are correct.


Ok, ignition advancer. Is a couple of small weights on springs buried deep inside the generator gubbins which move where the points open as the rev speed increases.

Look at the generator with the engine running. As you rev up, you should see the weights fly out under centrefugal force at a certain rev speed then fly back in again as the revs drop. If you see them moving then they should be OK. If you put a strobe on the timing marks, they will appear to move round as the revs increase then move back as they decrease indicating the unit is functioning. I don't know what to do If they aren't working, I have never had to fiddle with them.
____________________
“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.

[themadatter]

Thanks for the big chunk of info there !

problem is, I can't find what you are describing.

Here is my stator plate, with and without points in it; maybe it will help you help me !!

thanks !
Jamie

[themadatter]

ahhh i need to write something in here i suppose.

a pic _>

[ZRX61]

[themadatter]

Hi there,,

He was talking about an OHC and refering to the cam chain.

It doesnt have a ohc so obviously, no cam chain. hence the pushrods.

Things can come across wrong in the typing frenzy between checking email, getting ready to go out and trying to reply to a post !


I tried to stick a screwdriver in through the flywheel and adjust the points when the engine was running.
I was THAT close, but I had to admit defeat after shredding the 10th screwdriver. I'm just not as fast as I used to be





Jp

[stinkwheel]

I see what you mean, not as similar to the CB range as I thought.

Just been having a look at the manual for my H100, it appears that your original idea was correct, the gap and timing are adjusted using the same screw that holds the points on. You have done it right the first time. This is unusually basic, even for the japanese. Once the timing is set, you need to check the gap, if it is outside tolerance then replace the points.

That is stone age stuff! Even my old russian 125 was more sophisticated than that.
____________________
“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.

[mchaggis]

[themadatter]

Ahh,

thanks for all the info, and the nice diagram showing cam lobe !


I was rather hoping that somebody would say I had done it all wrong and maybe this is why my cg struggles to do 50mph...


thanks again!

Jp

[mchaggis]

I take it the fueling system is fine and clean, no blocked up jets, clogged up air filters or anything? If the auto-advance is working fine, and everything is sparking like it should be then that should rule the ignition issues. The valves do close fully when they're supposed to, don't they?

If the adjusters are too tight, it's not impossible that you're losing pressure by the valves not being properly closed, and they might be bouncing at high speed anyway. It's not a really likely thing to happen, but it's possible. Alternatively, is it burning any oil? It's possible that it might just be a bit old and loose, and need new rings to prevent any blowby and loss of compression?

If it makes you feel any better, my Mum managed to damage her CG125 doing 50-55 for 15 minutes or so. It blew the oil gasket on the valve cover and (we think - it has the symptoms) damaged a main bearing. It would never really get above 55.
____________________
I must not be a troll...
Mmmm, Guinness
Discovering the delights of Hammerite and a 3/4" brush.

[themadatter]

Ah well, I think ill just leave it.


There IS an electrical problem somewhere, as my dash lights and rear brake light dont work.

then yesterday all lights went out, even the horn.

and when i pressed an indicator, the N light would flash.

Suggests a bad earth, only problem is I can only find ONE earchon the bike, under the tank !

and its fine.


The flasher unit has 3 pins, in,out,earth,

On the wiring diagram it says that the should be earthed, but the earth pin was not used when i got the bike and they seem(ED) to work ok,, when i did earth it, the N light would flash rather than the indicators.

But being me i wonder why theres an earth pin if its not supposed to be used, and why if its not supposed to be used, is it not covered up,,and why does the wiring diagram say it IS supposed to be earthed.




truly baffled.

[mchaggis]

The CG indicators earth themselves through the frame, the earth wires are a little pointless on them, in fact I don't remember there being anything necessary other than a positive connection. If you can get a decent clean connection between the indicator stalk and the frame it might help.

There are earth connections everywhere, they're just not always hoops bolted onto the frame. Indicator problems were fixed on my Mum's CG by getting a new indicator altogether.
____________________
I must not be a troll...
Mmmm, Guinness
Discovering the delights of Hammerite and a 3/4" brush.

[themadatter]

oh.

would you know off hand, the location of these earth points so i can check them ?


the wiring diagram just gives symbols, you know how it is.

does your mums indicators flash at a different speed than normal indicators of today ?

the dash lights dont work either, ill be taking that apart tonite to check the bulb.

judging by the technology on the rest of the bike, it wouldn't suprise me if the whole things wired in serial, and the dash lights bulb failing has caused the whole electical system to fail like a set of old XMAS LIGHTS !


Jp

[mchaggis]

Not off hand, but I can check next weekend; at uni right now. The indicators did flash at different speeds, but not since we replaced the offending one. The neutral light has never been quite right, and the bike could sometimes keep running after the ignition had been turned off. Turning the bars to jiggle the connections fixes that.
____________________
I must not be a troll...
Mmmm, Guinness
Discovering the delights of Hammerite and a 3/4" brush.

[themadatter]

Never mind, i will go hunt them out tonite.

Thanks for the further support, info etc !

Jp