cb125 "nameless" Revived from the Shed!!!

ill look into the pitbike guys complaining, is there another solution that is sub 100$?


i know VM series mikuni carbs can be had for about that but really i just want to get this thing running. it has been sitting for a long time and i have too many plates on the road.


ill keep looking around.

I'd just look for a second hand CB/CG/XL/TL Keihin off evilbay or from your local breakers, or one off the chinese FM156 CG clones. So long as it has a 35 - 38 pilot and a 95 - 110 main, the sucker will run.
The pit bike ones are predominately for the horizontal engine.
I have no probs with the stock chinese keihin on mine, other than forgeting that it needs petrol, because it's so freaking economical that trips to the petrol station are a rare occurrence.

why are you looking for a larger carb? with out supporting mods (more then a "pod" and cut exhaust) you will run into tuning issues and might even make less power.

I would think you could find a good carb for $100-125

real trick would be to find a OEM carb that would work and snag it cheap on the bay....

like early SL350 carbs

i should clarify, i am not looking for a larger carb, i have one on there now and i think it is a 20 or a 22 kehin but don't hold me to that.


the problem is that it has floats that leak ( i tried to sauter them up to no avail, i also tried JB weld and that was a joke)
and the air mix screw was non existent when i got it, so in order to get it going stock i would need new floats, a new air screw, and a total rebuild kit.
these would cost more than i thought i could get a decent new carb for. like a VM22 or an OKO i definitely don't think i need a 30mm flatslide or anything, just trying to get her going.


for less than a c note, i have already bought a small stack of parts for this thing and once i have the carb sorted i can attack !!!!!!!! and maybe even ride this sometime.


maybe ill just post a want ad or keep on looking through the various motorcycle forums for something appropriate, if anyone has a decent used carb i will try to pick one up.

i think i figured it out.
those ones on eBay are what Mikuni calls a 22mm carb in CHINA... they actually make them, but they make them to lower specs. the sizes are slightly different and they are made from worse materials it looks like.


i think a genuine vm22 should cost around 50-70$ plus shipping and come jetted about right.


A chinese model one is like 25-35$ and has smaller jets. They come stock on chinese pit bikes and engines like LIfan dirt bikes and the clone motors for mini bikes and whatnot.


i did find some sites selling actual japanese made for US market VM22 carbs for 55$ or so and i think that is the route i am going to go.


I just have to take my old one off, double check the mounting size, and look up some jetting sizes so i can pick up a couple extra main jets incase i want to put new exhaust or air filter on it someday.


I will link the carb after i find the right spot to pick one up.

revheadgl said:

The carb size is stamped on the top af the carb as well as the choke slide when you look in the back of the carb. Anyhow pretty sure they are 20mm.

I would use one of these, Thailand built these bikes in huge numbers and parts a readily available and very reasonably priced.

http://www.ebay.com.au/itm/Honda-CB100-CL100-SL100-SL125-CB125-CL125-S-Carburetor-/350458508895?pt=Motorcycles_Parts_Accessories&hash=item5198f4765f

Click to expand...

+1

I had one of these bikes when I was younger, it was a fun little bike to ride around on, good luck with your build.

that carb in the ebayAU link comes up to like 64$ shipped. I can get a brand new VM22 for the same price i believe, not a clone or a round slide chinese mikuni but an actual VM22.


is there some reason to get that indo one? maybe it is cheaper for you guys because the shipping is so close or the Australian dollar is better in asia?

if there is nothing wrong with the carb body why not just rebuild it?
last time i rebuilt the one on my CL125s it was like $35-40 with a new float and everything

i neglected to mention that in an effort to repair the carb i tried to tap a new thread into the air screw hole to replace the air screw.


also i could not find floats with a carb rebuild kit that was that cheap shipped and all.


i did however find these for the mikuni VM22


http://shop.hyperformanceparts.com/Mikuni-VM-SERIES-ROUND-SLIDE-CARBURETORS-detail.htm?productId=8889341&rand=2490


I hadn't thought of replacing it with a new Keihin but I know more people using Mikuni and i know i can get parts local if i wanna swap it onto something else or need to rejet it.

I have listed this along with my pickup and a couple of mopeds for sale, we shall see what sells first, i may still have this but who knows.
it is in the buy sell forum here and craigslist in wilmington

I just picked up a bike that looks just like yours. My second 125 and my 3rd set of 125 carbs. They all had bad floats, i tried to repair them, in the end its best to just suck it up and buy the floats from honda along with the gaskets and rebuild it. Lots easier then trying to figure out what carb on ebay will fit and then guess at the jetting.

yea i saw LOLA when you posted it, they are so similar, but my carb has a buggered air mix screw also. that means even with new floats it is barely adjustable at all.


I have quite a bit of tuning experience and on a four stroke it is just a little easier. I really don't know why changing the jetting is so hard for so many people, and when conditions change jetting will need to change even if you don't change any equipment (like riding at elevation or temperature change)


that said, i charged the battery yesterday, took the tank off to switch both the top motor bracket and the coil w/condenser off my other parts cb125 and took it by the gas station to fill up the tank.


She fired right up!! rode all through the rev range and then got my lady on back and went for a 4 mile tour of the neighborhood!! it didn't leak from the overflow or the petcock and it came pretty close to holding a normal idle. It is still for sale but i may bump the price 100$ because now it is more exciting than ever.

for posterities sake when i was discussing a new carb there was some debate about the size on this bike. I cant say for sure it is the stock carb, but the KEHIN on my 1974 cb125s is a 22 on the top
i havent verified with calipers yet but i will if/when i replace the bad boy.

I know it is pretty dirty.

well that is it, i bought another carb (roundslide mikuni "24mm" ) but never put it on, i sold it just today, pretty bummed out about it but i made a little money on the thing, and had some fun putting around the hood and riding dirty to the beach.


what i really wanted was a two stroke and/or something hair bigger like a cb200 or maybe an rd200/ dt100 or any other of the bunch of small two stroke street bikes but anyway it is done.......


send this thread down into the bowels of DTT and I will likely be back again with another project to get going again.




thanks for all the help and suggestions for the fixes on the cb125, the guy who bought it was pretty happy and knowledgeable he turned the gas on, key, and popped the clutch and rode it over to his van.