CB125T2 from 1980

[hairygit]

The points ARE the earth connection, so yes, wired wrong will put things well awry!

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[K2-K6]

Yes, as hairy says, the points are the earth route for the coils so nothing should interfere with each discreet route for every coil via its own points set.

Also yes for the two sets of points,  by switching the two sets over with that earth wire from one to the other it will switch the spark timing by 180 degrees.
So if you just swap them and try it to see what you get.

[Bryanj]

Just to be pedantic the black/white wires are POWER in and the blue or yellow are the earth via the points, and it is easy to get the wires at the points wrong and earth the coils permanently so no spark

[peteuk]

Bryan regarding your post. I do have a spark at the plugs. Are you saying that if I have the wires wrong way round I wouldn't get a spark at all. I'm confused

[K2-K6]

I think what Bryan is saying there goes back to what was discussed a bit earlier in the thread around the insulation at the connectors of the points,  if it's not right then you wouldn't, as you point out, get any spark, so that end looks ok.

The colour coding is as Bryan states for feed and earth at the coils differentiated in that way,  but the coils will work when fed through the earth and switched with the feed. That would be connected to the loom backwards,  if that makes sense.

Which points are connected to which coil is what gives you wrong timing. So if you go from where it's currently at and just swap over the two leads going to the points it should verify if it will fire. You can do some tidying up with the colours afterwards to make it match the correct wiring diagram.

[peteuk]

Thanks for the advice. I'll give it a shot and let you know how I get on

[peteuk]

IT'S A RUNNER...........
Swapped over the coil leads and it started first time. Got a bit of an oil leak from the clutch casing when the oil pressure is raised. (Weird cos it's a new gasket on there) maybe just want nipping up. But any way, brilliant felling when it started up and kept running, good tick over. So I've decided to treat it to some new exhausts, new brakes, sort out the back end and a few bits should see it just about there.
Thanks for all the advice, tips etc. I'll post more pics when it's fully completed
Pete

[K2-K6]

Well done, it's great when you get something going after all the work put into it.

[Spitfire]

Great news, you should be well chuffed with it

Cheers

Dennis

[Laverda Dave]

Well done. When a plan comes together all the hassle was worth it. Look forward to seeing the video.

[peteuk]

Hi again. I've put a video up on you tube. It only last a minute or so. https://youtu.be/wctMcu72hS8

[peteuk]

UPDATE......
Hi, anyone following this thread will know that I got the bike running. Well not anymore. It was ticking over nice then suddenly stopped and will not start for love nor money.....and I've tried both.
I've stripped the carbs down....again and I definitely have fuel to the plugs.
Done the points gap and timing again
Cleaned the plugs and made sure there's sparking against the engine fins
One thing tho, I bought s new 6volt gel battery and i noticed it was losing charge. Took it off the bike to make sure it wasn't parasitic power that was draining it. Charged it up and left in on the work bench and within 15 minutes if had dropped from 6.3v yo 5.7v. I emailed the company who said this was faulty and are sending out a new battery.
Could it be that the faulty battery is causing a reduced spark at plugs?.
I was of the understanding that these old kick start Honda's were self generating and therefore technically you didn't need a battery to run. Am i wrong on this?
Anyway, when the new battery comes I'll try starting it again but ive wasted 2 days trying stuff and got nowhere and at the minute I'm totally stumped.
Please help

[hairygit]

They do indeed require a good, charged battery to run, low or dead battery and you have no hope! When the new one arrives, fit NEW spark plugs, after kicking it over 10 or more times with the plugs out, throttle wide open and choke off. Then fit new plugs and it should start normally again. Trying to clean plugs that have been soaked is rarely successful, and kicking it over as described clears any unburnt fuel from the cylinders and won't then foul the new plugs.

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[peteuk]

Wow thanks for the quick reply and I'll try exactly what you have said. Just one thing, choke off.....is that open. I tend to get this the wrong way round. Does choke off mean fully open and choke on mean fully closed

[hairygit]

Fully open, as if the engine is warm and running normally, just gives maximum airflow through the cylinders to clear unburnt fuel and not foul the new plugs!