Diff'rent Strokers

[crock41]

My recently purchased 3MA has a severe flatspot at about 5000 rpm, if the throttle is held open the engine will eventually pick up at about 7000 rpm when it will then rev freely.
Any suggestions?

[StrokerBoy]

The latest issue of Performance Bikes says that 3MA owners needing help and advice should contact... erm, us. Oh dear...

Have to admit I've not really done much work on mine luckily. There's a few areas to look at - check the powervalves are working properly, have a look at the solenoid-controlled air jet thingys, clean and check the carbs and all the airbox/filter/tubing. Quite complicated for just a parallel twin really.

Best thing is to just point you at the archive of useful info already on the TZR Forum : 3MA section. Warwick and Martin are the men to speak to, although they do come on here sometimes too.

[martin77]

Unfortunately it's almost impossible to give a definate answer to your problem, as a flat spot like that could either be rich or lean running. Does it cough, splutter and spew forth smoke from the pipes, and needs more throttle to clear? if so it's rich.... If it makes a sort of hollow groaning noise and picks up a bit when the throttle is backed off, then it's lean.

As Stroker boy says...make sure the PV's are in good order, strip and clean the carbs, try adjusting the pilot mixture screws etc etc...

Sorry I can't be more specific, but these things are complex enough, even without a problem.