Honda CG Head drilling for carb

[Ross47888]

Hi, so I bought a 1978 Honda CG. It has a 1984 CGE engine in it, that the owner said was just rebuilt with a new piston (first warning sign). Turns out the engine was almost certainly not rebuilt, and it seized less than 10 miles after buying it, top end seizure. I'm living in Andover atm but I can't work on the bike here, so I brought the engine in suitcase home by bus / boat to Northern Ireland to work on it.

After looking at the piston etc I ordered this head and barrel kit off ebay https://www.ebay.co.uk/itm/352716574424?itmmeta=01HYXQ6HP2HQAYVXNF0EJ1MQS5&hash=item521f8bced8:g:LZEAAOSwRKtciOSr

Problem is the this bolts for the carb on this head don't line up with with the original carb / head. Since it's just aluminum am I fine to just drill it out, tap it and run carb through the new holes? Picture should be attached comparing two different heads.

So am I fine to use this head if I drill two bolt holes for the carb or tilt it on its side? Or do I need a new head. Thanks.

[WD Forte]

As long as the holes aren't too close to the edge of the milled casting to cause weakening then yes.
Dont tilt the carb, it wont like it.

I feel a bit leery if this 'Genuine Honda' thing on Ebay
the bike doesn't even have honda badges on it and looks like
a Pakistan honda not Japanese honda which the listing could lead you to believe
Plus the carb on that bike has level carb studs, not tilted ones.

It may fine for all that and i'm not an expert on all things CG so hope it works out for you
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[stinkwheel]

I bet that was a new piston. Just the wrong size.

And yes, if there's enough metal there, I'd drill and tap.

EDIT: Port diameter looks smaller on the new head.
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“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.

[Evil Hans]

Or get a flange adapter? Something like this might do it?

https://www.ebay.co.uk/itm/204714139801
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[Ross47888]

[cresad]

Hi

Just make sure you don't go to deep , saw similar on daughters ybr and it broke through into the oil way.

Adam

[P.]

I think, going from some diagrams, that's a 1995 or CG S model. Only one with vertical mount holes. Everything 81 onwards till then appears to be horizontal.

https://www.cmsnl.com/honda-cg125-1995-s-england_model2608/partslist/E__0100.html

Weirdly carb is listed as a horizontal hole mount...all list different jet and float sets too, which ties in with a smaller carb hole that Stinkwheel mentions. I imagine they changed a few things.

[WD Forte]

Broadly speaking CG here
78 bike 84 engine that's still 6v electrics and points ignition right?
I dont think they went 12V CDI until the 90s?
____________________
bikers smell of wee

[blurredman]

[Rob Fzs]

[Ross47888]