CB125T2 from 1980

[Johnwebley]

doing really well,

  please continue to post pics with updates

[peteuk]

Hi. I've got the chance of a cb125t engine for the bike from a 1988 bike. Mine is a 1980 bike and was wondering if anyone could tell me if it would be a direct fit or a suitable replacement. Thanks

[hairygit]

You would need to do quite a bit to get it running in your frame. It may well fit physically, but your bikes electrics are 6 volt and set up for kickstart only. The later engine you have bee offered will be 12volt, and electric start only, no kick start option. Plus you would need to make a loom to suit the cdi setup as your frame uses points ignition. Not insurmountable, but a lot of grief and fair bit of expense. And for less bhp than your original engine would have!

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[Rob62]

The engine from a honda cb200 benly from the same period was very similar looking with the same style rocker cover if i remember correctly....

[peteuk]

Wow thanks for the info. I forgot about the reduced bhp too. I think I'll hang on and wait for a more suitable engine then. Thanks again

[Spitfire]

Keep posting as this is the type of thing that fascinates me, the idea of a bike appearing from a pile of parts is great, it's nice to see it progressing.

Cheers

Dennis

[peteuk]

Cheers Dennis, the tank is off and is currently going through the derusting process of the inside then it gets lined and i'll be sending it to a mates for a paint job. i was going to do everything myself but ive decided to let someone who knows what they're doing tackle the paintwork. i've also got quite a few parts on order..handlebars, seat, brakes etc. Still trying to source an engine. Theres one on ebay but the seller says it won't turn over right so not sure if i want to invest in that one. I may do cos they're like rocking horse poo to get hold of. Anyway i'll post some more pics soon when its looking a bit more together.
Cheers everyone.....Pete

[matthewmosse]

Do a bit bit of research, if the cm125 rebel can donate any engine internals, I have a decent lot of bits less a crank off a crashed bike, cases snapped in half, crank bent but otherwise looked ok. If the one on eBay won't turn over it's a fair chance the piston or bore have got rust, very often the rest is ok, probably worth a gamble as at least you have a starting point, provided the delivered cost is acceptableof course.

[peteuk]

Thanks matthewmosse, the sellers reply when I asked him if it turned over, said that it turned over 350 degrees one way then got stuck then would turn 350 degrees the other way?. I think he possibly meant 360 degrees ie a full rotation but I was thinking it's possibly a bent valve or something.
Any way, he's located 150 miles away from me but I don't mind the round trip to collect if it's worth getting.

[peteuk]

Hairygit, regarding your earlier message:-

You would need to do quite a bit to get it running in your frame. It may well fit physically, but your bikes electrics are 6 volt and set up for kickstart only. The later engine you have bee offered will be 12volt, and electric start only, no kick start option. Plus you would need to make a loom to suit the cdi setup as your frame uses points ignition. Not insurmountable, but a lot of grief and fair bit of expense. And for less bhp than your original engine would have!

Thing is the bike came without an engine so therefore as long as it fits in the frame, am I right in thinking I just need to make sure everything is 12volt ie lights, regulator, battery etc. Sorry if I sound like I don't have a clue but basically that's not far off the truth. Cheers

[hairygit]

Well, yes you can convert to 12v, but you will need a lot of additional parts, and a considerably larger battery, switchgear with start button, solenoid, cdi unit, probably easiest to use the harness from a 12v bike, then regulator, rectifier, coils, flasher unit, horn and all bulbs. I had the impression you were trying to keep it fairly original, but as I said, not insurmountable problems, but a fair bit of aggro and expense.

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[peteuk]

Hiya Hairygit, no im not keeping this one original, I did with the cb550 but this ones having black and white paintwork, cafe seat etc etc. As for all the parts you mention, I didnt get them with bike anyway. Engine, carbs, electrics, rectifier, battery all missing so i would have to buy them anyway and from looking round, 12v supplies seem much easier, and cheaper, to come by

[peteuk]

Hi, I will be posting some more pics soon and I have managed to get a 1978 unrestricted 125t engine which is a bit of a bonus. The engine was missing a few parts, ie points plate and points, inlet stubs and carbs etc. Anyway I've got these parts on order but I'm puzzled by the points, in particular the condensers. On previous bikes I've had the condensers were bolted to the points plate underneath and attached to the points. Not so on this bike and I've searched everywhere including the manual and I can't workout where they're supposed to go or where they're supposed to attach to (which wire etc). Any help with pictures would be greatly appreciated. Thanks

[RGP750]

I'm picking up 2 bikes from my Father in laws after work tonight ,both Hondas
Both are 125's i seem to remember a twin and a single i think.
They have been left outside in an old green house for some years s not sure what i am going to find.
I would like to get one of them going for him (he is now in a home)
but may move the other one on .
If it is the same as yours may be of use for reference.
Watch this space

[Yoshi823]

Hi PeteUK

The condensers for the points ignition are mounted on the battery box. Not sure why. I remember on my '72 CB125s that I first rode in '75 had the single condenser under the points cover, but there's no room on the CB125T2.