Rich/Lean Adjustments Question

Since my '70 CT70KO was running much too rich so adjusted the Carb Slide Clip one increment and now it's way too lean. Can't get that chocolate brown. The Manual says Spark Plug Gap is between 0.24 and .027. Does that make much difference? I've tried a cooler spark plug NKG-CR7HSA and then tried again, but didn't really make much difference. Could it actually be because I didn't install the back Air-Filter boot when I replaced the fuel lines?

Gap should be .027 or .028 and CR7HSA IS the normal factory plug. a CR6HSA would be cooler but that is not going to solve the issue you have. Try putting the boot on possibly put the clip back and tweak the mixture screw afterwards.

OLD CT said:

Gap should be .027 or .028 and CR7HSA IS the normal factory plug. a CR6HSA would be cooler but that is not going to solve the issue you have. Try putting the boot on possibly put the clip back and tweak the mixture screw afterwards.

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I heard just the opposite here. Someone said 7 was cooler than 6, and putting the boot back on would involve WAY too much work that I just went thru changing the fuel lines. I runs good. Just not perfect. Lol. I had to remove everything awhile back as the intake manifold bolt going into the Cylinder head was stripped and I had to heli-Coil it. For some reason it was murder getting the exhaust bracket on the bolt at the end of the seat. I'm actually sick of working on it, and since I ride in the desert and the mountains (I recently sold my CRF250, the air mixture has extreme changes. I have my deposit on the new CT125 ABS and I'm 2nd in line at a huge Honda Dealer here in So. Cal. They're supposed to come in November, and as soon as I get it I will put the CT70 up for auction at the big classic car auction they have here in Palm Springs twice a year (before the Pandemic). One went for $4500 last year! Even though I love Vintage and Classic Cars and motorcycles I'm getting too old and son's won't appreciate them. I recently sold the Taco 44 Mini-Bike I restored. It was just like I had when I was young before my dad bought us a new 1970 Honda Z50 Trail 50. I restored it for my son, but ended up getting him an XR50. Here he is on the Taco.

Go by how it runs. There's rarely more than two acceptable jet needle height settings, with one delivering clearly better results. Unleaded fuel changed the plug reading game, post-2006 era gasoline all but killed it. That "ideal chocolate color" isn't going to happen, no matter what you adjust. One can still see too lean, overrich and traces of oil, if they exist. That's pretty much "it" with plug readings in these engines. At best, you'll see a light tan coloration on the electrodes with the plug body color ranging from charcoal gray to black. It's okay, normal results of oxygenates and chemical scavengers added to gasoline.

Korbon, last night I got my plug wires crossed. NGK the higher the number the colder the plug. Champion Autolite and Bosch, higher the number the hotter the plug.

OLD CT said:

Korbon, last night I got my plug wires crossed. NGK the higher the number the colder the plug. Champion Autolite and Bosch, higher the number the hotter the plug.

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No Problem. In fact I got my 'wires crossed' too. I meant to say I tried changing the NKG-CR7HSA to a NKG-CR6HSA just to see the effect. I had a new one in my spark plug tray that was for my '98 XR70R. Lol.