CB750
Well,first topic, I'm happy so far, bike is running much better.
I followed the idle jet drill procedure by the HC website.
Thanks to SOCH4 and all the supportive members.
Anyway, The Pile, as I call it, was headed to the dump a couple years after my friend totaled it on one of our cross town jumps to do a good deed. It sat in his Dad's barn for like 2 years. Mice or a rat moved into the airbox (I'm not a turd or nest expert).
One season my buddy got a hot date off the internet and next thing you know off to another state. He mentioned they were dumping it I said dump it off at my place, so he and his Dad did so.
So, I tossed the airbox back then( I know cringe - whatever), and slapped on the uni-pods and tried to piece the damage back together.
Stator, motor metal covers, gauges, kickstands, exhaust, handbars, chainguard etc - most everything was bent or broken or smashed. Hammer, and chisels and and straightening and some welding. I didn't buy parts, just a bit of cash for tire essentials and it has kind of limped for years.
So trying to get it decent enough to be a halfway reliable scoot and the misses has taken a few rides now and loves it. ( good enough that she isn't scared to mount it anymore.
)
Idle jet #3 had a grey chippy wet gunk covering and chunks out the idle jet holes. It was so bad I couldn't believe it.
wiki:
80 0.0135 in/0.343 mm
79 0.0145 in/0.368 mm
78 0.016 in/0.406 mm
77 0.018 in/0.457 mm
It was very difficult trying to drill them at first - ran a #79 through them which was good practice and only very slightly over 35 jet size, then finished up with a #78 once my body and brain adjusted to the tiny, tiny world.
I also wintergreened the boots, had done the drill bench sync on a prior carb pull, I've made a manometer it's ready and waiting... float level & clear tube check etc. (Did a valve clearance a few years back.)
Don't have much time now but I just got the carbs on and Wow !
Started right up - ran better than it ever had in the past without touching the idle screws (1.5 out) or run syncing.
Very happy.
Will try sync and idle later today hopefully.
Anyway here's the drilling the jets pic below. I bought the #61-#80 tiny drills at Home Improvement for $12.99.
Tried to modify mech lead pencil (plastic) which didn't work very well before I finally located my old xacto with the X tip used for drilling.
Thanks for the website help people.
