Honda CG125

Anything else ya ride!
User avatar
alihar07
Posts: 50
Joined: Sun Feb 26, 2017 1:41 pm
Rides:: C90 '88 (red) Now gone: NT650V, Bullet B5, DR350SE, TDM900, XL650V & XL1000V
Location: Leek, Staffordshire

Honda CG125

Post by alihar07 » Tue Jun 21, 2022 9:56 pm

Evening all,

Since my Deauville has been written-off, I've been looking at a 125cc bike to replace it in the "faster-than-the-Cub" section of my motorcycle collection. I'm not too keen on the most modern 125s, since they mostly seem to have been designed so that they have angular plastic all over them. Mainly due to this, I've set my sights on a Honda CG125; I like the old fashioned looks more. I have searched the rest of the forum for info on the CG125, however I cannot see much definitive information displayed in a concise manner on this model. There are a few other reasons for me being transfixed on a CG125 too. They have an OHV engine, negating the need to replace cam-chains. Additionally, they are fuelled via a carburettor, which are relatively easy and cheap to sort out if anything should break/stop working correctly.
However, does anybody have any advice and experience regarding the best "generation" of CG125 to go for from a reliability and usability point of view? I'm mostly thinking of a 1990 to mid-2000s model because they seem to be in relative abundance. The post-2004 models have a slightly larger 13 litre fuel tank and front disc brake (pre-2004 have drum-brake and 12 litre tank), which occurs to me as being quite beneficial considering how ineffectual the drum brake is on the front of my cub. The pre-2004 model has a full chain-case, which I do like. Could the full chain case be fitted directly to the post-2004 models without modification if I were to purchase one of those? Also, is the build quality consistent throughout it's production?

Thanks in advance.

User avatar
Capitano
Posts: 5104
Joined: Wed Oct 27, 2010 8:05 pm
Rides:: '92 C90, '97 Divvy 6, 24V e-bike
Location: West Sussex
Contact:

Re: Honda CG125

Post by Capitano » Tue Jun 21, 2022 10:39 pm

Our late, great friend SteveW started a CG125 topic a few years back.

There may be some useful tips in there.

viewtopic.php?f=37&t=26285

User avatar
Alan CF
Posts: 6619
Joined: Mon May 09, 2011 6:10 pm
Rides:: CUB RACING small cc engine rebuilds crank repairs
Location: CHESTERFIELD

Re: Honda CG125

Post by Alan CF » Wed Jun 22, 2022 7:32 am

Hi, had a few cg125s and seen a few engines come in for refurbish, this doesn't mean there bad, it's just the previous owners neglected them,
The early k1 models (1976 1978 ) are good,
They have the normal 5 speed box, points ignition, but are 6v electrics,
Honda did bring out a heritage model for the year 2000 that looked like the early k1 model, it was a 12v bike but it was only a 4 speed box, david silver bought a very large batch that was destination for China as there Mail delivery bike,
But the order got dropped at the last minute,
He was knocking them out cheap, but are now seen as a rare model and the prices have increased for this model,

Now the Brazilian models are a nice bike, 5 speed, 12v electronics, still have a carburettor, if you can find a nice clean one,
Points to watch out for, Nothing, there's a good well built bike,
Engine wise, try to keep away from the JC30 engine,
This is just my view, seen to many come in with snapped conrods,
The jc30 engine had a 13mm gudgeon pin ( same as the c90 ) and thinner conrod then the other cg125s they all had 15mm gudgeon pins, it also tended to drop valves,
They were 5mm valves instead of 5.5mm valves on the other models,
Jc27 or jc18 are good, along with the normal cg125 Brazil engines,
Also look at the XR125L they also have the cg125 engine.

These are just my views from working on these engines.

User avatar
Capitano
Posts: 5104
Joined: Wed Oct 27, 2010 8:05 pm
Rides:: '92 C90, '97 Divvy 6, 24V e-bike
Location: West Sussex
Contact:

Re: Honda CG125

Post by Capitano » Wed Jun 22, 2022 8:45 am

Alan CF wrote:
Wed Jun 22, 2022 7:32 am

Engine wise, try to keep away from the JC30 engine,
Excellent summary, Alan. 8-)

How would we know if a CG125 has the JC30 engine?

User avatar
alihar07
Posts: 50
Joined: Sun Feb 26, 2017 1:41 pm
Rides:: C90 '88 (red) Now gone: NT650V, Bullet B5, DR350SE, TDM900, XL650V & XL1000V
Location: Leek, Staffordshire

Re: Honda CG125

Post by alihar07 » Wed Jun 22, 2022 9:11 am

Thankyou both. I'd had a look at that previous thread already, just couldn't find anything regarding the differences between each version, so had resorted to the Wikipedia page and Honda history section on their website.

The JC30 identification was about to be my next question actually...
Capitano wrote:
Wed Jun 22, 2022 8:45 am
Alan CF wrote:
Wed Jun 22, 2022 7:32 am

Engine wise, try to keep away from the JC30 engine,
Excellent summary, Alan. 8-)

How would we know if a CG125 has the JC30 engine?
Is there a specific date or engine/frame code for the made in Brazil variants? I'd prefer a made in Japan one if possible, although if their quality is good for both types then I'd consider either.

User avatar
Alan CF
Posts: 6619
Joined: Mon May 09, 2011 6:10 pm
Rides:: CUB RACING small cc engine rebuilds crank repairs
Location: CHESTERFIELD

Re: Honda CG125

Post by Alan CF » Wed Jun 22, 2022 9:23 am

I belive there from about 2003 to 2008 ish,
They are all electric start engines,
But I would ask the seller to confirm engine number prefix before setting out,
I wouldn't take my worries on board to much if there looked after and not thrashed around I'm sure the jc30 engine
Will be fine.
I have a chart somewhere saying what specs the jc and cg specs were.

User avatar
Viper254
Posts: 489
Joined: Fri Apr 19, 2013 12:16 am
Rides:: C70C (12v) (1983), CB250 Nighthawk (1991)
Location: Stoke-on-Trent

Re: Honda CG125

Post by Viper254 » Wed Jun 22, 2022 3:26 pm

I've had a couple of CGs and feel the made in Japan thing is a bit of a red herring; the Brazilian CG were excellent quality as well. Look for mid to late 90s - CDI ignition, still full chain cover, built like a tank and still not quite as desirable as earlier/later models.

Mid to late 90s is the period I have in mind.

The lights are appalling, even for a bike of that era.

User avatar
ally
Posts: 616
Joined: Mon Dec 09, 2013 4:51 pm
Rides:: dr750, mz skorpion traveller, v90, v75a, c90-g, innova fi, fj1200, CG125ES
Location: lincoln
Contact:

Re: Honda CG125

Post by ally » Wed Jun 22, 2022 8:19 pm

I've a 2006 brake disc model that is in the queue for fettling (clutch and weeping head gasket, it was very poorly maintained as I found out...) and was surprised how well it handled

I have decided to reduce my fleet as my mobility continues to worsen, it's on the kill list so I can purchase a cb125f, undecided on the innova but the c90 is staying!

:)

User avatar
alihar07
Posts: 50
Joined: Sun Feb 26, 2017 1:41 pm
Rides:: C90 '88 (red) Now gone: NT650V, Bullet B5, DR350SE, TDM900, XL650V & XL1000V
Location: Leek, Staffordshire

Re: Honda CG125

Post by alihar07 » Fri Jun 24, 2022 11:23 am

I've been doing a bit more research on the JC30 engine models, and it appears that any CG125 with a disc brake (All Post-2004 bikes) has the JC30 engine, as Alan indicates in a previous post. I did manage to find a table which had the specifications for each year of bike, not sure how to post the photograph here however at this time... :D There are a few of the disc brake models for sale near me, but I am slightly put off by the thought of major engine failure. Not sure how many out of the thousands they will have produced actually have had this problem, probably a tiny percentage, but I would like to reduce the chance of having a major failure by going for an earlier bike, especially as I cannot tell whether they have been thrashed necessarily from external condition alone. :(

User avatar
alihar07
Posts: 50
Joined: Sun Feb 26, 2017 1:41 pm
Rides:: C90 '88 (red) Now gone: NT650V, Bullet B5, DR350SE, TDM900, XL650V & XL1000V
Location: Leek, Staffordshire

Re: Honda CG125

Post by alihar07 » Fri Jun 24, 2022 11:27 am


Post Reply