triumph hesitation

hey-my 70 650 bonneville hesitates badly when i take off. is clip on
needle which attaches to slide mechanism supposed to be on top or
middle or bottom slot?
any help appreciated. ed.

 

Impossible to say unless you can tell us whether the bike is 100% stock
or has been modified in any way.

And if by "hesitates badly when I take off" you mean "hesitates when it
comes off idle" it's unlikely to be the needle setting anyway - more
likely the pilot setting. But you can always change the needle positions
to check yourself.

Actually, on a 1970 Bonnie, it could be anything.... ;-)

 

What kind of carburetors? Amal concentrics? If I had a nice-looking
Trumpet with Amals on it, I would sell it to Ted Mittelstadt as a
collector's item and let him suffer with the starting problems once or
twice a year when he takes it to motorcycle shows.

If I had a mediochre looking Trumpet that I wanted to ride everyday, I
would swap it for a nice 1976 Norton Commando. If I couldn't find
anybody willing to swap his Norton for a Trumpet and about $1500 cash,
I would install a set of Mickey Rooney carbs on the Trumpet.

Mikuni carburetors are so much more tunable, they have five circuits
instead of the three circuits that an Amal had. Mikunis add emulsion
*air* to the jet tube and to the idle jet, mixing the gasoline and air
together *before* they ever get to the mixing chamber.

Mikunis are much more responsive to small throttle openings, which is
where your problem seems to occur.

But, let's just *ass-sume* that you have Amal carbs on your Trumpet and
that The Older Gentleman's toothless Uncle Fester hasn't tried to make
an air filter out of old red shop towels, and that TOG's drooling
nephew Cletus hasn't kept his pet hamster in the Trumpet's air box.

The first thing I would do is clean the ignition points and set the
timing and replace the spark plugs. If *that* doesn't fix the
hesitation problem, *then* I would turn the idle mixture screw
clockwise about half a turn to see if that helps. It reduces the amount
of air in the idle mixture.

But, what's this stuff about jet needles? Has TOG's transsexual twin
brother Brucie been at your carbies?

The clip on a jet needle is usually installed in the second slot from
the top, or in the middle slot. If you find that you need to put the
clip in the lowest slot, your main jet is far too small for continuous
high speed operation.

But the whole business about jet needles is off the wall and people who
mess with the jet needle are usually clueless about how the needle
works in series with the main jet.

The clueless ones are usually just messing around with the needle
because they read a tuning guide somewhere and they didn't understand
anything about how the various circuits in a carburetor OVERLAP, and
what circuit they are mainly using at any given time.

If you're having problems with off-idle hesitation, you work on the
idle mixture circuit, but only after you get the ignition system
working perfectly.

 

You are being unusually poisonous, so I shall not snip what you've
posted and merely post comment.

He doesn't have Mikunis so all the above is irrelevant.

If you are trying to be witty, you really need lessons.

See above. I'm quite interested in your reference to transsexuality,
actually - bringing in this sort of reference from nowhere, in my
experience, speaks volumes about the person making the reference.

It is interesting that the last regular here to behave like this was
Hoyt.

Depends on the bike and the carb(s). Impossible to generalise.

This is very true.

So, actually, your advice is, once one has removed the usual Hemingway
dressing, what I said earlier. With the added, and wise, advice to check
the ignition.

Serious question here: why do you feel the need to write so much
irrelevant stuff? Reams and reams of it? I mean, the end advice is
pretty sound, but apart from the need to show off, or possibly the
desire to bore audiences rigid, I can't see why you drone on like this.
Brevity is the soul of wit, and a few other things besides.

 

I was clip clopping across a wooden bridge this AM, and a troll ran
out, shaking his fist...

Sometimes it takes a lot of clip-clopping to wake the troll up...

 

You really, really aren't showing yourself in your best light, you know.

 

Heh.

And a Ducati, Kawasaki and Honda owner, too.

And in the past, Suzuki, MZ, Triumph, Moto Guzzi, Morini, Jawa.....

 

Hey, I'm sorry. I didn't know your twin bother Brucie was that way. It
was just a joke, yannow...

 

The clueless ones put down Amal carbs because they don't understand 'em.
They're simple, work great, and easy starting in all weather conditions.

 

Oh, yass. Amal carburetors are so wonderful nobody has used them since
1979...

 

Nope, sorry, still not funny. Just offensive, were I to take offence.
And still showing yourself in a poor light.

 

Still on sale, still being bought, still being used.

http://www.amalcarburettors.co.uk

Next pearl of wisdom?

 

Ya-a-a-a-wn! There'll always be an England, and collectors will want
new old crocks to keep in their garage while it rains endlessly.

 

But isn't this what you've been spoiling for, a flame war in
rec.motorcycles.tech?

I guess you just can't please some people.

 

Pardon, but your ignorance is showing.

 

No. You, OTOH.....

 

So you were wrong, then?

 

No shit.

 

Are you going to write this down on your list of grievances too, Dustin?

 

<Shakes head, sadly>