well im a goose :-)

[petejw1966]

hey pg,
your 78 and my 81 carbs are different,
stock, my jets came out 110 across, i think yours came with 137.5?
with the dj kit i can run a bigger main jet,
i read the plugs the way you do, with a 138main dyno jet, there isnt
a complete ring on the base ring,
my drill bits only go up in increments of .1,  ive also tried using 130, and 140
mains, the 150 put a nice ring around the base but its still a little rich for my liking.
Im also running a clapped out engine that likes to burn oil which makes plug
reading even harder.
its running quite hard, it wants to lift the rear and spin the tyre on acceleration,
i just need to spend some more time with it,
ive been freezing my nuts off at nite test riding it. 

[pgnz]

hey Pete with free-flow filter, piped and drilled airbox on my stock carbed 78E,  I ran some drilled-out 1.5mm jets but they're definitely way too rich for the mikuni 34mm carbs,  gas milage suffers and the chambers and valves get sooted up after a while.  The 150's may look clean after a plug chop at hi revs but the insulator doesn't indicate the true story. It's the base of the ring on the plug that shows how clean it's running.  I went to 147'5's then 145's then finally used 142.5's which were perfect.  Doing some top speed runs laying flat on the tank and hanging on grimly, there was always a 5 - 10 kph increase in top speed with the 142.5's over the 145's on mine

[petejw1966]

ive been running my bike with pods for the past
four years, im running foam uni filters fitted with an inner
spring that i have slipped over the velocity stacks that have
been removed from the air box, ive since fitted a dyno jet kit
from the states for the past 18 months, ive been tuning/tinkering with this thing
on and off ever since, yesterday i remove the pods to give em a clean and remove
them from the v/stacks, this time i remove the inner springs from the uni filter and refit them
over the v/stacks and take the bike for a spirited ride, the engine would break down once the slides opened fully, eventually i realize the rubber v/stacks were collapsing on them selves, and cutting off the air, it was also doing this with the springs fitted but no where near the same extent.
so i went out and got some 40mm pvc pipe and cut it down and champhered and fitted them inside the rubber v stack,
heres a pic



i was originally running a 13o main dj, which was running lean, the 138 main that came in the kit was running rich, with the above fix the 138 is now lean, i drilled out a mikuni main jet to 150, this is slightly on the rich side but runs heaps bettet,  ive ordered sum 145 mikuni mains to see how it runs.