B Bryan Riegner New Member Jun 22, 2009 #1 Put new plugs in 3 year old sportster during winter- engine runs smooth and starts easy but thrust won't get speed over 25-30 mph. LAt year topped out at over 40. any ideas?
Put new plugs in 3 year old sportster during winter- engine runs smooth and starts easy but thrust won't get speed over 25-30 mph. LAt year topped out at over 40. any ideas?