1975 Honda CB125S

It shouldn't be rich if float height is correct. Either shut off valve isn't sealing or float level is too low.
I pretty much always set float level +1mm when airbox is remved.
You should need about 10% larger main jet , pilot jet will be fine as original filter was virtually zero restriction at low engine speeds.
You will probably have to drop needle rather than raise it
I found some pictures of back light fitted but 'lost' them again ::)
 
I've checked float. I think I finally have it set right. At least I hope it's right. I believe I have it set at 24mm. I'll have to try a plug chop to see how its running. It seems to be really, really rich at idle/no load revving. I did also raise the needle one notch. I'll drop it down 2, 1 below stock and see how that affects things. I'll figure out carb tuning one of these days even if it kills me! ;)
 
At least carb is easy to get on and off and you only have one to worry about ;)
 
Pretty sure it's running lean. Moved the needle down one from stock. Runs better, but still stalls after it warms up. Need to go up a few sizes on the main jet. Pilot jet still good at stock size?
 
The 75 should be good on pilot size, they didn't start getting stupid lean until 78~79. Check carb specs on a 74 to be sure though. You shouldn't need more than 15% larger than stock unless you run no filter and short pipe (without any form of silencer or pipe extension)
 
The needle jet is a 98. Stock says it should be 105. Pilot I think is a 38 if I remember correctly. Which is correct. Couldn't find this style jet anywhere on JetsRUs. About 34mm long, 8mm wide threads, 8mm nut. But it is a Kehin. It has the styled K on it. Cleaned the jets out some more and it helped a good bit. They must have not been fully clean and smooth.
 
Your probably looking at the jet still in the emulsion tube. Hold the 8mm hex and unscrew the jet out. May be stuck so look and feel like it's one piece.
I wouldn't have thought about it if you adn't mentioned some sizes, had the same issue when I was tying to make jet set up 'long distance' for someone on here a few years ago. Went on for weeks mailing stuff back and forth until he mentioned something similar.
98 is main jet, needle jet will still be in carb body. It's a transitional size with different needle, use 105 ~ 115, may be lightly rich mid range but dropping needle should sort things out
 
vwrabbit said:
Carbs are fun, mmkay!

They are when your watching someone else 'fix' them ;)
I still can't find pic of tail light on bike so I did a quick eBay for one
http://www.ebay.com/itm/Lucas-Style-Motorcycle-12V-LED-Tail-Light-For-Triumph-British-Cafe-Racer-Chrome-/262759607036?epid=2102678645&hash=item3d2db16afc:g:k28AAOSw6DtYTrBt&vxp=mtr
I particularly wanted bare alloy as it is more 'traditional' for a 60's style cafe. The prices haven't jumped too much since 2010
 
6v headlight finally gave up the ghost to the 12v battery. Would like to convert to LED. Thinking H4 LED conversion using the existing lense. I'll need to cut a hole in the back of the headlight, remove the current headlight guts and get an H4 bulb holder affixed to it.
 
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