Finally some news to report. I and my friends effected a 20 mile ride yesterday. The day was clear amd 59 degrees at an elevation of over 7000'msl. I was a bit apprehensive about the initial stages of the ride because it is in a mountainous region of New Mexico with a steep grade out of the area and a climb of several hundred feet over a 1/2 mile. All of my life-time motorcycle riding (all 200 miles of it) has been done on the flats. I was a bit concerned about making the climb at proper gear and rpm and proper technique on the decent while riding a bike with a freshly rebuilt engine.
The bike performed well on the climb and decent and pulled nicely up in 2nd gear at moderate rpm. A combination of engine braking and front/rear brakes kept everything safe on the decent.
I missed one considerations on the run, namely carburetor adjustment. I had the carb set to run smoothly, adjusting idle IAW the TM for an elevation of 3500msl where I live. We rebuilt the engine and attached the carb with those same settings and I did not readjust the low speed needle, only the idle after she warmed up. As a result, at the higher elevation, (double) where the air is markedly thinner, it was running rich. The problem manifested itself first when I slowed at the the turn around point and down shifted into second at lower rpm. The engine hesitated and sputtered going into 2nd and was a bit problematic accelerating. At higher rpm in the flats, she ran smoothly, until I slowed again to make the turn into the hilly area. The sputtering was much worse, and the engine died. SHe would not start after repeated attempts.
I waited 2 minutes and tried again and my friend noticed a large black exhaust discharge with smell of unburned fuel. We concluded the engine was running rich. BIll rode ahead to get two clean spark plugs and a wrench thinking they were probably fouled. While he was gone, I turned the LS needle in about 5 clicks. She started right up, ran rough at low rpm, but I was able to get home in 3rd and 2nd gear.
Upon return we did the following checks.
1. both cylinders were at fairly even temperature to the feel.
2. We removed the plugs and they were extremely black and sooty showing a reduction in gap where carbon had built up (I was running far too rich)
3. We checked compression in the cylinders, (Rear 54, Front 50) All very normal at that elevation, indicating slightly over 5:1 compression ratio. We put a few squirts of oil in the front to see if the rings were sealing well and did not get any change in the pressure reading.
4. We drained the oil and analyzed. No visible metal flakes on the magnet, and the oil was still nice and "clear". We refilled with fresh 60 wt oil.
5. We installed everything and tightened everything up.
6. We adusted the idle and LS needle for the higher elevation and the bike idle sounding nice.
7. Made one more short run to temperature and found the plugs clean as a whistle.
SHe is back home now where I will continue to get the carb adjusted for my elevation. I added my NOS breaker cover retainer and the Cadmium breaker cover from Way Back Wheels and it took the bike closer to correct in terms of parts with the right finish. Still have several small items to correct, but that will happen in a few years after i ride.
Here she is parked in my workshop among the refuse of parts for my 1941 Dodge WC12 restoration.
NOTE: I was happy to notice that the bike rested for nearly 3 weeks between the last run and it was nice to see NOT ONE DROP of oil anywhere on the bike or on the ground.
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