Triumphrat

waynemags

hello all. wayne again. im asking for some help with jetting. im gonna tear them apart tomorow and see whats in there. for now heres the problem. runs rich right off the top. when going down the road, give her full throttle and she sputters. roll off a little and she picks up again. just wondering wher a good base to start from would be. air screws are at 1 1/2 turns out.starts great, usually second kick, no choke, warm or cold. pipes are black. after a ride plugs are black on right side and a little less black on other side. its my 650 1971 bonny. wondering what yous are running.

72TIGER-X

hi again,
going by the parts book i have for the 72, the 650 bonny should have 190 main jet, .106 needle jet, #3 slide cut out. see what you have. maybe your needles are not in the middle groove, if they are try them in the top groove

waynemags

will do.

waynemags

ok. heres what i found. both carbs looked like they sat for 30 years. very dirty inside. one was pluged at the pilot(low speed) jet. the main jets are the ones in the middle that screw into the emulsion tube. no numbers on either. they were odd looking to me. mikuni carbs, the main jet hung down deep into the bowl with a little rubber oring on the end of it. never seen that before. couldnt see the numbers well enough on the pilot jets to read them for certain. both needles are in middle position. cleaned everything up as well as i could, and put it all back together. started fine. when you hit the throttle hard from idle, she wants to die. moved the needles up one position, still about the same. anyone know a good website to find a set of good carbs, and what exactly to look for? as i said before, i would like yours advise, as you have all been there with these bikes. thanx again.

rousseau

Wayne
I not sure about your Mikunis. But if they don't have booster(accelerator) pumps then this is common. I know the original amal carbs don't and If you "whack" the throttle wide open from idle It will surley die almost everytime.

pookybear

Waynemags,

Mikunis eh. So when you test drive this thing, and you are
going down the road does it does fine for just crusing along?

And I would think that your problem is when you punch it a
little more, say around 4,000 rpm or so, and have about 3/4
or more throttle in the carburators. And the engine make a
nice Blat, Blat, Blat sound instead of the usual purr.

Is this right?

If so your bike is doing something called eight stroking. A clear
indicator of the main jet being to large. Basically you are flooding
the engine with too much fuel.

Pookybear

pookybear

Oh forgot to mention, my new jets are sitting right in front
of me, to do this job. However, I am waiting for a new coil
for the ignition system. That has to be sorted out first as
it affects the carburators as well. Weak coil is sooting up one
sparking plug.

Anyway, I shall let you know how it works out.

Pookybear

waynemags

ive got #2 slide cutout. supposed to be 3. will that make it rich from idle on?

pookybear

Well Waynemags, it is not helping one bit with it being over
rich. Try to get back close to where it needs to be, but again
I thought you have Mikunis. I shall hopefully be working on my
carburators tomorrow.

Pookybear

Plewsy

Hi waynemags.
are you running Mikuni's or Amal's,
190 main, 106 needle jet, std needle and #3 slide is the data for Amal's