Unevenly smoking exhausts issue solved (probably)

[yeadon_m]

Had a bit of a tinker today with the GT750A, which I also rode yesterday.
I've had it since 2009 and always been a little bit troubled that the right outer never smokes and the baffle remains dry. We see posts like this from time to time, so thought someone might find this useful or maybe interesting.
I'd long ago proven that:
-the oil pump is fine. I'd even swapped it for a proven spare, no difference.
-the oil line check valves 'seem' to have the same cracking pressure (to oil injected with a syringe)
-the oilways are all clear (syringe feed)
-if oil is injected via the incoming SRIS line, it smokes on the RHS.
-and I can see oil being injected from the brass stub tubes in the intakes, when cranked on the starter, oil pump arm to max.
Today, I removed, cleaned, checked (good) the RH SRIS valve but on replacing it, I used a stub of SRIS hose to plug the valve, and likewise I plugged the disconnected line.
Went for a ride and, on getting home, noticed the RH outer is faintly smoking, slight, but quite distinct and more so when I held the pump arm open (this never made any difference before).
No idea how or why, but one conclusion is the RH SRIS valve works so well that any excess gets whipped out to another cylinder. When that system is plugged, there's clear evidence of oil delivery. I plan to leave it like this for some while and see what happens to the baffle. In due course I might plug all the SRIS circuits. My 380B doesn't have this system and has always smoked in a reassuringly even way.
I kinda always knew it was fine on the 750A, and I've done many thousands of miles with no problems, but it irked me that I didn't know why it didn't smoke. Little things please little minds, eh?
Cheers,
Mike

[Alan H]

That's the problem sometimes Mike, instead of listening to the music, we're listening for the pops and crackles on the LP.
Figuratively speaking of course.

[Roger Ackery]

Thanks Mike,mine used to switch its smoking habits between the left & right top pipes regularly....lately everything pretty even ?
A new problem is a very wet left top baffle/exhaust,my suspicions of this is the left hand CV diaphragm has a problem,.....like not working as it should Sometime ago now I repaired a torn diaphragm with Loctite glue which worked really well.Apart from now having one very wet & very clean baffle I think the throttle feels a little heavier too use,also the bike sounds a bit "blubbery" at low revs under 3,000rpm. I've adjusted the oil pump back,this has helped lessen the problem of the rear guard & taillight getting covered with muck, but because the oil is so watery/thin, I think it's more fuel than oil,?
PS it doesn't smoke excessively from the left pipe at all, much the same as the other three,which isn't much ! Doing my bit for the environment

Top Photo right pipe
Bottom Photo left pipe

[Rijko]

thanks Mike,

buddy of mine has a similar issue and i am collecting
as much info as possible to properly approach testing where the
problem may reside.
Loads of useful info on this forum !

[yeadon_m]

Its a pleasure, Rijko, to learn that sometimes my rambles and obsessions prove useful to others
Mike