150cc kit for CG125

[Wrighty1991]

Has anyone fitted a 150cc kit to a CG125?

I have been looking at doing the same, there are a few different kits floating around online/eBay like the below:

https://www.ebay.co.uk/itm/Honda-CG125-OHV-push-rod-type-engine-150cc-Big-Bore-Kit-Straight-Fit-15mm-Pin/273245343767?epid=699566668&hash=item3f9eb11017:g:k60AAOSwWxNY0vP9:rk:1:pf:0

Do they require much modification? Or are they pretty much plug and play? I have read online about people having to enlarge open the crankcase with a dremel etc.

I would be fitting it to a 1999 CG125

[Mr Fro]

I've read that too. I think it would be a squillion times better to nip the barrel down with a lathe.

[fastbob]

The first one I looked at on eBay says " Straight fit on to crankcase" 64mm outer bore . So there you go . HOWEVER, this one costs £90 All the cheaper ones state that they fit CHINESE engines so I think there may be some modification needed to fit these to genuine Honda crankcases. Some state 62mm inner bore so assuming the cylinder wall is at least 4mm thick they ain't going to fit without a fight. I think it might take a bit more than a tickle with a Dremel . I'd probably go for the £90 one from a UK seller . You could message them first to check .