150cc conversion for CG 125

[moonzoomer]

I have a Chinese copy CG125 branded Sukida and was thinking about converting to 150cc as the kit is easy to find and not expensive @50 quid, has anyone done this conversion and if so did it improve the bike in any way worth talking about.

[andys675]

you will get a couple of horsepower out of it, the reason they're so easily available is that in some countries the learner limit is 150cc and often our 125's are sleeved down 150's or vice versa
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Some people feel the rain, others just get wet.

[binge]

Unless you are going to fit a bigger carb (or at least up jet), and alter the gearing to suit the extra power, it'd be a wasted mod.

But yeah, it'll work I guess. Have a look on ebay at the 250cc upright engine'd pit bikes. Pretty sure the whole engine bolts straight into a CG125 anyway.

[1198]

There's many 150 bbk's on eBay for some cg125 copies - eg those fitted to the Huoniao hn125. For about £100 or so - big bore kit, carb, air filter (cone type) and a different front sprocket - it'll make for about 5mph more top end, or more relaxed cruising at 50 without the engine being near the red line.

[Rogerborg]

Careful now. The Sukida is about as generic as they come, but the same engine code doesn't necessarily mean the same engine, or that everything will line up precisely. Make sure that the seller warrants that the barrel will fit your specific engine.
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Biking is 1/20th as dangerous as horse riding.
GONE: HN125-8, LF-250B, GPz 305, GPZ 500S, Burgman 400 // RIDING: F650GS (800 twin), Royal Enfield Bullet Electra 500 AVL, Ninja 250R because racebike

[moonzoomer]

Thanks for the replies, I will check if the barrel will fit before buying.

[1198]

As Rogerborg says, check first! There's a lot of minor differences, even on the Huoniao there's at least two different types of engine, a 156? And a 157? From what I remember each type of engine needs a different type of bbk.
I'd look to see if there's a forum for your specific brand. There would be all the info you need - it's a fairly well travelled road!

[bradh511]

Ive fitted few of 150 kits depending on what model cg you had depended on the size of the crankcase opening. Brazil cg had the right opening .. My cg ended up with ar 125 back wheel and a normal front one and was pretty nippy hit indicated 80 mph lol with ar125 geanring
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Theory 11-10-12 lets hope i get mod 1 and 2 done by the 18th of jan 2013

[Rogerborg]

The OHV CG copy-engines can come as either 156FMI or 157FMI. All this means is that a given manufacturer has decided to round 56.5mm bore measurement up or down for their engine code.

You can get them with or without balancer shaft, with one or two exhaust ports, and just to make it more confusing, there's also a CB copy OHC engine which I've seen coded as a 157FMI when the CB bore was apparently 56mm.

And then there's the Suzuki based 125, which is usually (but not guaranteed to be) coded K157FMI.

Allah loves wondrous varieties.
____________________
Biking is 1/20th as dangerous as horse riding.
GONE: HN125-8, LF-250B, GPz 305, GPZ 500S, Burgman 400 // RIDING: F650GS (800 twin), Royal Enfield Bullet Electra 500 AVL, Ninja 250R because racebike

[moonzoomer]

I have 2 of the CG clones, one branded Sukida model SK125 -2 and a Superbyke model SB125, both are identical bar the Superbyke having 3 sets of footpegs and have the same manufacturers plate (Zeng Cheng Halli), the engines have slightly different finishes but other than that the bikes are identical right down to the rather well made rear carriers, the Suzida has 19k miles on the clock and really needs a rebore and piston (using oil) so I reckoned it would be just as handy and certainly no more expensive to change the barrel and piston due to the low cost but now I am thinking about the cylinder head as well, not sure if these model have a 150 head with a 125 barrel fitted for the UK market though I would doubt it due to the smaller bore.

[pepperami]

Come back and tell us what you found and how you got on.
interested in this
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[humanbeing]

Most old CG clone that made from Guangdong https://www.motorfans.com.cn/bbs/viewthread.php?tid=134674&extra=&originator=yes&authorid=75082 can't fit std CG150 kit.
They need these "special" kit https://item.taobao.com/item.htm?id=39507761712 . CAn't find in fleabay, u need agent…

[moonzoomer]

I have ordered this kit which fits the 156 fm1/2 model engines though there are 2 different sizes of wee end pin @ 13 and 15 mm though the 15mm seems to be the most common and both are easy to find, this kit fits the Sukida pharoh models 1-5 and the Superbyke branded models 1-4 https://www.ebay.co.uk/itm/150cc-Cylinder-Big-Bore-Set-for-Sukida-Pharaoh-SK125-2-/161392752852?pt=UK_Motorcycle_Parts_13&hash=item2593c1f8d4 a cylinder head is also available which includes valves and springs
https://www.ebay.co.uk/itm/UK-Stock-NEW-150cc-Big-Bore-Cylinder-Head-For-CG125-Engines-156FM1-2-/321588627405?pt=UK_Collectables_OtherTransportation_RL&hash=item4ae02d07cd