FZR400 poor running :(

[Jizzmeister]

I've been having a similar problem with my FZR 400 (genesis) 1986

However it was air leaking in through the perished old carb rubbers that caused the bike to
idle at 3-4k rpm. After paying £60 to get genuine Yamaha rubbers the problem was sorted
or so I thought. Recently the problem has come back (only went away for a couple of weeks)
so I'm left wondering what I've done wrong. I've tried adjusting the idle and it obviously isn't
that.

The other problem is starting the bike in the mornings has become considerably harder
very white smokey exhaust gives the impression the piston rings are shot?? or perhaps
so valve/timing issue is to blame for the poor starting.

Either way I have the xmas hols coming up, so if I can find a donor engine/rings cheap enough
I could probably get it sorted.

Help plz.

[Evilchicken0]

White smoke ... is usually steam - I'd say your head gasket has gone.

Have a look ing the radiator filler ans see if there's a tan coloured scum in there.
Check the oil colour - is it a dark grey as opposed to black.
Open the oil filler and see if there's brown scum / water droplettes / dark grey oil it.

[ARn13]

white smoke, if u havent got symptoms of a blownheadgasket just like what Mr. Evil mentioned, probably more to do with our colder weather which nothing to worry about.

[Taggyd]

cold, or your race mechanic has been spraying wd40 down the pipe so that it will make a nice flame out the back eh sharpey???? though the stink might give that away!

[Jizzmeister]

Thanks for the speedy replies!

When I replaced the clutch plates (about 3 weeks ago) I noticed the new oil left
in the bike overnight turned a translucent grey colour. When I removed a section
of the coolant piping (by the gear lever) a rusty brown scummy fluid came out.
I replaced the coolant and water but havent checked it since.
However, the oil looks black viewed from the oil filler.

I don't think the white smoke can be steam as there is so much of the stuff.

I will try and get my hands on a compression tester so I can see if the rings are
ok. If they are I will try and get my hands on a head gasket and replace that over
the holidays.

Thanks again guys, If this fails I think I'll have to invest in a new bike I'm not sure
the effort of fitting another engine/parts in the bike is worthwhile.

[alfie600]

hi there exup probs i have tidy std sustem free 2 a good home call me