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From: kylentz on 5 Aug 2006 18:14
I have a 1982 Yamaha XJ650 Maxim with about 11K miles on it.

The problem is that it is very hard to start or won't start - unless I put a
very small amount of starter fluid in the air box opening. Once I do this,
it starts right up and runs well. Idles a little slow until warm (I think
this is normal). After 2-3 minutes, idles and runs great. Once the bike is
warm, it will start again with no problem at all. I have tried starting it
with the choke in various positions. With the choke on full, it will
sometimes sputter for 1-2 seconds, and then die. Then it seems like once it
has done this "sputter" thing, it won't even fire until I let it sit for
about 15-20 minutes. One 1 second shot of starter fluid seems to fix the
problem completely.

Here is what I have tried so far:

Cleaned carbs. (twice, very thoroughly, a big pain)
Replaced the jets in the carbs (main and pilot, the second time I cleaned
the carbs)
Replaced fuel line
Used a gas tank restoration kit (insideof tank did have a little rust)
Added an inline fuel filter (works the same with or without the inline
filter installed)
Replaced air filter
Inspected intake boots carefully for leaks.
Tested the vacuum activated fuel petcock

Obviously it is not getting enough fuel to start, but I am baffled why such
a small amount of starter fluid seems to completely fix the problem.

I have not synchronized the carbs. The previous owner said they had just
been sync'ed. Since it idles fine once warm, I don't this this would be the
problem, but I am not sure.

I would appreciate any advice.
From: ShadowHawk on 5 Aug 2006 18:58
1- Join the XJ Owners email list at :
http://www.micapeak.com/lists/XJ-OWNERS
This is where the heavy hitters for the XJ series of engines reside and
assist with you to work on your bike.

2 - The symtoms you describe are indicitive of a fuel delivery problem.
Most likely in a couple of clogged pilot/starter circuit.

When you replaced the pilot & main jets... did you use the Haynes manual
for placement of them? If so, be aware that the Haynes manual for the
650/750 engines has the main/pilot jets reversed in more than one edition
of this manual.... It's also possible to install the fuel floats upside
down... (Don't ask me how I know this!!)

G'Luck - and I'll see ya on the XJ Owners list!

Rex S.
'82 XJ650 Maxim
'82 XJ750 Seca



kylentz(a)excite.com wrote in news:XK8Bg.1121035$xm3.701002(a)attbi_s21:

> I have a 1982 Yamaha XJ650 Maxim with about 11K miles on it.
>
> The problem is that it is very hard to start or won't start - unless I
> put a very small amount of starter fluid in the air box opening. Once
> I do this, it starts right up and runs well. Idles a little slow
> until warm (I think this is normal). After 2-3 minutes, idles and
> runs great. Once the bike is warm, it will start again with no
> problem at all. I have tried starting it with the choke in various
> positions. With the choke on full, it will sometimes sputter for 1-2
> seconds, and then die. Then it seems like once it has done this
> "sputter" thing, it won't even fire until I let it sit for about 15-20
> minutes. One 1 second shot of starter fluid seems to fix the problem
> completely.
>
> Here is what I have tried so far:
>
> Cleaned carbs. (twice, very thoroughly, a big pain)
> Replaced the jets in the carbs (main and pilot, the second time I
> cleaned the carbs)
> Replaced fuel line
> Used a gas tank restoration kit (insideof tank did have a little rust)
> Added an inline fuel filter (works the same with or without the inline
> filter installed)
> Replaced air filter
> Inspected intake boots carefully for leaks.
> Tested the vacuum activated fuel petcock
>
> Obviously it is not getting enough fuel to start, but I am baffled why
> such a small amount of starter fluid seems to completely fix the
> problem.
>
> I have not synchronized the carbs. The previous owner said they had
> just been sync'ed. Since it idles fine once warm, I don't this this
> would be the problem, but I am not sure.
>
> I would appreciate any advice.
>

From: FB on 5 Aug 2006 22:20
kylentz(a)excite.com wrote:

>
> The problem is that it is very hard to start or won't start - unless I put a
> very small amount of starter fluid in the air box opening. Once I do this,
> it starts right up and runs well. Idles a little slow until warm (I think
> this is normal). After 2-3 minutes, idles and runs great. Once the bike is
> warm, it will start again with no problem at all. I have tried starting it
> with the choke in various positions. With the choke on full, it will
> sometimes sputter for 1-2 seconds, and then die. Then it seems like once it
> has done this "sputter" thing, it won't even fire until I let it sit for
> about 15-20 minutes. One 1 second shot of starter fluid seems to fix the
> problem completely.

I have explained this a bazillion times. Your motorcycle doesn't HAVE a
choke. It has a bypass enrichener system. It's a little valve in a hole
that bypasses the butterfly. There is a fuel passage that sucks
gasoline straight out of the float bowl.

When the idle mixture circuits get dirty, the engine begins to stall,
and the owner will adjust the idle speed screw to make the engine idle
faster.

This defeats the bypass enrichener. When the butterflies are open too
far, the engine vacuum is too low to suck up enough mixture to start.

The solution to your problem is to add about 4 ounces of Berryman's
B-12 Chemtool Choke and Carburetor Cleaner to a full tank of gas and go
for a ride.

When the B-12 starts cleaning the idle mixture circuits out, the idle
speed will increase and you'll have to turn it down.

By the time you have run a full tank of B-12 through the engine, the
carbs should be spiffy clean inside.

> I have not synchronized the carbs. The previous owner said they had just
> been sync'ed. Since it idles fine once warm, I don't this this would be the
> problem, but I am not sure.

Carburetor synchronization is a moneymaker for mechanic$ in
$tealer$hip$.

When the carburetors get dirty inside, sure, the engine is going to run
rough on one or two cylinders. Run some carburetor cleaner through the
gasoline on a regular basis and you never need to synchronize the
carburetors.

I used my cheapie Carb Stix exactly twice and wound up throwing them
away.

From: Paul Gustafson on 6 Aug 2006 00:37

"FB" <flying_booger(a)yahoo.com> wrote in message
news:1154830833.321980.44430(a)75g2000cwc.googlegroups.com...
> kylentz(a)excite.com wrote:
>
>>
>> The problem is that it is very hard to start or won't start - unless I
>> put a
>> very small amount of starter fluid in the air box opening. Once I do
>> this,
>> it starts right up and runs well. Idles a little slow until warm (I
>> think
>> this is normal). After 2-3 minutes, idles and runs great. Once the bike
>> is
>> warm, it will start again with no problem at all. I have tried starting
>> it
>> with the choke in various positions. With the choke on full, it will
>> sometimes sputter for 1-2 seconds, and then die. Then it seems like once
>> it
>> has done this "sputter" thing, it won't even fire until I let it sit for
>> about 15-20 minutes. One 1 second shot of starter fluid seems to fix the
>> problem completely.
>
> I have explained this a bazillion times. Your motorcycle doesn't HAVE a
> choke. It has a bypass enrichener system. It's a little valve in a hole
> that bypasses the butterfly. There is a fuel passage that sucks
> gasoline straight out of the float bowl.
>
> When the idle mixture circuits get dirty, the engine begins to stall,
> and the owner will adjust the idle speed screw to make the engine idle
> faster.
>
> This defeats the bypass enrichener. When the butterflies are open too
> far, the engine vacuum is too low to suck up enough mixture to start.
>
> The solution to your problem is to add about 4 ounces of Berryman's
> B-12 Chemtool Choke and Carburetor Cleaner to a full tank of gas and go
> for a ride.
>
> When the B-12 starts cleaning the idle mixture circuits out, the idle
> speed will increase and you'll have to turn it down.

I usually head for the nearest steep downgrade, make sure no-one is behind
me, get up to about 45 mph (or whatever your first gear redline speed is)
then downshift to first and pop the clutch with the throttles closed. Repeat
a few times and the extra suction on the idle passages in the carburetors
ensures that the carb cleaner reaches the clogged passages. Works like a
champ. Just be sure you are prepared for the resultant engine braking when
you let go of the clutch lever.

FZ6 Vet

From: FB on 6 Aug 2006 14:37

e wrote:

> we're talking about an 82 here.

As if the OP didn't mention that from jump street...

The $tealer$hip mechanic$ won't touch it. His other choices are to let
some unreliable independant mechanic store it in his junkyard workshop
until he finally gets around to fixing it, or to ask total strangers on
Usenet how to fix the problem himself.

You got a problem with me telling him how to fix it for $3.00?

> and you'r so LeEEt $ for s bullshit is childish.

Using "$" for "s" isn't elitist. This is elitist: ÓÕÃË ÍÙ
ÄÉÃË, ÆÁÇÇÏÔ!

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