My son has been fixing up an 81 R100T. Using a timing light at idle the timing mark lines up per the chiltons book. Being an old school seat of the pants guy, the bike cranks over like the ignition is too advanced and at highway speed it doesnt pull like I would expect. Could an 81 have mechanical advance with electronic ignition? Or is it a full electronic ignition system? Compression is good, we did a total rebuild on the carbs and the sinc is as close as i can get it. To me it acts like theres a timing issue. My only idea is to very the TDC mark is accurate with the piston at TDC. Any suggestions?