What are the common problems/weaknesses with the TL?
Jarmo Kaila: 1.) The worst weakness must be the infamous 4-stroke off-idle cough and hesitation. When suddenly opening the throttle off of the idle position the engine “coughs”, hesitates for a while and then goes (well, goes as well as you can expect from 4.5 HP). This feature certainly rewards a smooth riding style. Big bore or stroker kit should help. Note that pumper carbs are not allowed in the AHRMA “modern classics” class (although I think they should be). 2.) If you experience any difficulties in stalling the bike in slow speed sections you may want to try retarding the ignition. This will result in slight loss of top end power, but you won’t notice anything in trials riding (maybe different for street riding where you really get to use the top gears with WOT). My recommendation is to set the static ignition timing correctly and scrape a mark on the ignition points back plate. Then set the ignition to fire at TDC (there is a mark on the flywheel for TDC) and make another mark.
