WR400 jets+mods


I would some help on my 2001 WR400. (Netherlands import)

The bike needs 4 twists of the accelerator, full choke and a good kick and it starts every time. When the engine is hot it starts first kick with the hot start knob.

I have notice that the exhaust pipe coming out of the engine turns red/orange (HOT) after 2 minutes fast tick over. The bike seems to perform well but on one occasion lost some hot water/steam though the expansion tank. This as made me wonder if it is running weak. I am thinking of changing the jets and also making additional mods to give more power. I have read articles about throttle stop, grey wire and de-octopussed could someone please help.

:) The header turning red is normal, so no problems there, No grey wire to do on Euro models, it's a US thing for emmisions, ditto the throttle stop, though the easiest way to check is to remove the plastic cover from the RHS of the carb and check the length of the brass stop that prevents the throttle wheel moving any further, if it's huge(about 17mm) then it needs shortening, if its about 10 mm (ish ) leave it alone, some peolpe have had problems with removing them altogether,

De-octopussing...well it gives you back control over your pilot circuit, as the Octopuss artificially richens the circuit to prevent popping on over run etc, also less chance of an air leak thru all those hoses,

Jetting....well.....now there hangs a tale, there is a rather large thread on just this subject, called jetting Q's which would be a good place to start, Good Luck :D

P.s. have you checked your PM's in your profile?

as I sent you one earlier.


Guy :D

bleed your coolant water so that it's continuous from the cap. you know how, like water and jugs when you were four!


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