Motorcycle Repair: followup on no throttle response, exhaust leaks, engine rpms

Question
QUESTION: Mike. This is a follow up on previous questions concerning no throttle response. I built a custom and was doing break-in of the engine. The first ride the bike ran great, also on the second until I lost throttle response. The bike idles fine. These items I have checked, compression, carb, coil, spark plugs and leads and also have checked for intake and exhaust leaks. Have also gone through timing procedures. When I put into gear to take a ride the engine falls flat. I am using a Ultima single fire ignition. I have talked to other mechs on this. They all seem to think, if it is the ignition it would go completely. The leds on ignition indicate no problem and also when I advance or retard the timing I can hear the difference in the engine RPMS. I think it is breaking down. Is there any procedure to troubleshot this type of ignition.

ANSWER: You will have to refresh my memory since I get so many questions. What motor are you running? What color are the plugs? If the bike is sitting and you rev it does it break down?
Mike

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QUESTION: Mike, the engine is a 113 cu. in. Ultima. The plugs have black soot on them, but I think that is from idling to check for problems. If I roll the throttle it does break down. When you put into gear and start out, thats where it just fall flat.  I orginally sent (no throttle response)around the 17th or 18th of Dec.

ANSWER: the plugs would indicate that you are running rich, which would cause the falling flat.Even siting and ideling for a while you should have black plugs. Your ignition is nothing more than an on-off switch, so I dont think thats the problem. Generally, when an ignition goes bad, it just doesnt work.
I would start by re-testing the coil and plug wires for OHMs, just to make sure they are ok. If they are ok, then you need to look at the carb. You are probably have to big of jets in it. Cleant he old plugs and start the bike and re-adjust the air/fuel misture. A good test is to install new plugs, start the bike and go for a short ride. It should run ok, until the plugs start to foul and then start running flat.
Happy holidays
Mike

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QUESTION: Mike, I put in new plugs and new spark plugs leads. Had already replaced coil. Also checked them to make sure they are good. Still no throttle response. Also checked fuel for dirt or water. Pulled plugs, no soot looked better, but this is only in idle. I havent replaced the jets yet, since the bike was running good at the start of the breakin, and until I can actually get back on the road to see if they do need to be changed out. Do you think, this is an engine problem, possibly valve or lifters? I did a compression check on both cylinders, they seemed good (started at 140 psi and increased on each stroke up to 190). I would figure that this indication should eliminate the valves or lifters. I have checked and rechecked every thing over and over again, but still have the same problem. Im about ready to throw in the towel.

Answer
Your compression is fine. Couple of questions. What carb are you running, are you using solid lifters or hydrolic, when you say you lose throttle responce, is the bike bogging down or popping throught he carb or exhaust, and what type exhaust are you running?
Mike