Got a problem with the balancer/crank shaft on my 2017 Speed triple, as luck has it she is in Webb's (Lincoln) for her second service, They are sorting her out under warranty. I would just like to say that I have been using Webb's since the 80s and without doubt they are the best dealer I know.
Not spoke to anyone out of the service side of Webb's (Andy), but I am off tomorrow to Lincoln, if I were to hazard a guess I would say it is not the right shape, possibly when the engine gets hot and the elliptical shape of the actual weight on the balance shaft changes,,,,just a guess
My fellow triplets, if the balancing shaft is a piece of white mans magic to you I have attached a YouTube video with an American bloke explaining so even I understand you're aware of the rocking couple generated in a 3-cylinder with no balance shaft. Each revolution, the engine will tend to rock end to end. The balance shaft will have an offset weight at one end, plus another offset weight at the other end, 180 degrees out of phase with the first. By phasing the balance shaft correctly, the out of phase up/down motion balances the rocking couple of the pistons. However, with a single balance shaft, the same balance weights induce a left/right rocking couple instead. The solution is to have two balance shafts, rotating in opposite directions. The balance shafts cancel out each others' left/right rocking couple, and work together to balance the up/down couple produced by the pistons.
The same Geezer explain how the 3 pot engine works, this is a car engine but exactly the same principal as the Triumph engine
