dollydog wrote:........... have you got a t500 pump you could strip down......
Uhh... Yes.
GT250
I've been meaning to strip down at least one of these again anyway to hopefully confirm my thoughts back when, that excess smoking (2T) cannot be exclusively blamed on banjo check valves, wrong adjustment, etc., that is, my thinking a few years ago was that a worn rotating plunger shaft and of course its bore could cause excess oil to bypass around and be discharged with the rest of the metered oil. Pumps out there that in the vast past that have been run dry for some period of time or even worse, have been disconnected from the oil tank and left still bolted on by some that would choose to run pre-mix. Thus increasing the population in the wreckers/salvage yards, though..... ironically.... increasing bike parts availability for us vintage enthusiasts. My theory on this could be wrong....I don't think so...it's just I believe that was my thinking when I last had one apart several years ago. I just need to look inside at the 'works' of one of the pumps again.
Note...it appears to me the reverse thread screw is being shown screwed in the wrong direction but otherwise pretty neat little clip..
https://www.youtube.com/watch?v=1x5Dau9N9cg" onclick="window.open(this.href);return false;"
From what I can remember, each of my spares (at least two previosly used by me) had some kind of issue, save one, that I might not have tested yet.
I can remember many years back on this forum and others that the general consensus was that you should not take one of these pumps apart....that they were not meant to taken apart. Way back when, the idea was to replace them with new ones when they did not meet the discharge rates supplied to the service departments of Suzuki dealerships. I seem to recall that warning is even in one of my service manuals? ............another indication from the manufacturer that just plain wear over the years in these pumps can make them NOT "bullet proof" as many have described over the years?
I'll try and get a chance in the next couple of days to take one apart as you requested.