Yamaha recently brought out its new modified exhaust for its for its YZR-M1 MotoGP bike at Misano race test, confirming the delivery of the predictions of modifications for the bike that Neil Spalding who is the MotoGP race technical guru had predicted two weeks ago.
Yamaha had experienced a series of engine failures at the two opening events at Jerez which had been caused by faulty valves as the team tried to change engines so as to get the maximum out of the bike, but this has lead to rev restrictions have been minimised by 300rpm for the Yamaha riders as they struggled in Brno and Red Bull Ring last month.
Yamaha’s problem can be however rectified by using a new and longer exhaust system, changes were evident on the bikes of Maverick Vinales and Valentino Rossi.
“Yamaha definitely cooked some of their engines right at the start of the year, and that damaged the valves, but sealed engines mean they’re not allowed to change those valves. So they’ve got to run the rest of the year with those engines and now they’ve got to find a way to put them under less stress.” Neil Spalding explained.
“The only way to do that is to reduce the maximum revs and then try and build all of the equipment on the outside of the sealed engine to try and help that engine make its best power lower down the rev band.
“That is typically going to include modified throttle bodies inlet lengths and most critically a new exhaust system with longer primary pipes and a longer overall length to help the engines make better power at lower rpm.”