CB125 overview

Well, as ever, there were a few bodges. It seemed to be running leav,
and I could see a small gap between carb and inlet manifold casting, so
removed the carb. Someone had put in an O-ring that was too thick, and
hadn't bolted up the carb tight.

So I bolted it up tighter and the throttle slide seized.

Ah - the O-ring is too large to compress, and I'm distorting the whole
carb. Eek. Oh, and the manifold gasket is missing.

In my boxes, locate a handful of CB125 manifold gaskets, select one,
plus one smaller O-ring, and refit carb. Oh, and replace the missing
hose clip on the air filter attachment, to get a decent seal. That's
better.

Oil, filter cclean, tappets. Camchain... well, it's still a bit clattery
at low revs, but it's better at higher revs now I've adjusted it.

Runs sweetly. Everything works.

Only slight niggle is I think the carb is suffering from Gunge
Suyndrome. I cleared a lot of crap out of the float bowl, and it doesn't
really tick over. If you wind out the throttle stop screw, then once the
idle drops below 2000rpm, it just cuts out. And if you have the throttle
WFO, it just hesitates around 7.5-8k revs, but picks up cleanly if you
ease the throttle shut a fraction.

Classic bunged up pilot jet passage, methinks, so some of that there
carb de-bunging fluid is needed.

Seat is utterly originasl and barring a tiny rip, perfect. All chrome is
remarkably good, considering its age. Paintwork is original and
extraordinarily good for the age.

I think I'll just MoT it and Nige it on Fleabay.

 

Works rather well, that. See Motosport ...

Sounds pretty good.

Well, then maybe not.

 

Remind me. What's the name of the gunk again?

Is it the stuff you sling in the tank?

 

I'll have to check - I used to buy it at a Motor Factors. It's simply
labelled carb cleaner.

Nope aerosol nastiness, full of good stuff like Toluene and similar.

 

STP Carb Spray Cleaner is what I have, and I'm 99% sure I got it at
Halfrauds.

Ding


--
Mike Buckley
RD350LC2 GPZ750 Turbo
http://www.toastyhamster.freeserve.co.uk - deleted by Orange - f*ckers
http://www.toastyhamster.plus.com
BONY#38

 

It's called 'Wynn air intake and carb cleaner' - as mentioned, it's an
aerosol, not a petrol additive.

 

Are there any recommended petrol additives?

 

Right, then, my SL125 restoration needs some attention. I've been
looking for a front wheel for one for ages, in order to take the hub and
get it re-spoked and re-rimmed. I also have a brand new rear rim,
hanging on the garage wall, looking for a hub.

So I've bought this:-

Item 300141086513

I'll take the wheels off, and get them rebuilt. They can then go onto my
SL125. The carb can go on the CB125, as a swap-over. Maybe the whole
engine, if it's really good.

Any other nice SL125 bits I'll keep (I've discovered the SL is in the
Motosport class of scarcity).

And my old SL125 wheels can go on this hybrid, which will then go back
on Ebay.

I wind up with a sorted SL125, a sorted CB125, a 125 field bike, and a
pile of bits, somne of which I can keep, and some of which I can sell.

Nice job.

 

The only one I can think of here in the UK is the 'Forte" stuff, but
that's fairly hard to get. My RX-7 specialist has it.

That said, in order to clear a blocked jet I'd use one of the aerosol
products.