Topica Loopframe_Guzzi Archive


Subject: RE: Hot misfire

Author: Kevin Graf

Date: Aug 9, 2002, 12:41 PM

Post ID: 1710772280


Yeah, I hate that test too.... pretty funny when someone else has to do it
though. Just the anxiety knowing you got to do it is enough to kill ya.

Kev

-----Original Message-----
From: Zerhackermann [mailto:chopp-@hotmail.com]
Sent: Friday, August 09, 2002 3:28 PM
To: Loopfram-@topica.com
Subject: RE: Hot misfire


Okay...
The tach points to something elecrical. Cause those are run off the
coil...no?

I'm betting on loose plug wire or cracked cap. I had a similar behavior
on my way to moto I one day. I got 15 miles down the road and the right
cylinder dropped off. I would let it sit for 5 minutes and then get
another mile downthe road. I nusrsed it to moto and put on a new plug
wire and cap and it was all good.

There is an easy check. One is exciting the other isn't. with the bike
warmed up, and running, grab the cap on the offending cylinder. If your
hair stands up and you walk around in circles with your arm dragging
like you have a broken wing...it's bad. Or you could just take the bike
into a shady or dark spot, rotate the cap so the tail is closest, but
not touching the cylinder and fire it up. If you see a blue spark arc
between the cap and the head. Then it is bad. BTW on mine it wouldn't
start to arc visibly until I ran it up the RPM a ways.

-----Original Message-----
From: Richard Arimoto [mailto:arim-@cemrc.org]
Sent: Friday, August 09, 2002 10:18 AM
To: Loopfram-@topica.com
Subject: RE: Hot misfire



Kevin Graf wrote:
 When you say it jumps around, is it like a short sharp wiggle, say
from
2 - 2 1/2 back to 2 or a long drawn out jump, say from 2 to 3 1/2 back

 to around > 2 again.

It's a fairly rapid deflection of the tach needle that goes from around
idle up to 4K+ even though the engine definitely isn't turning that
fast.

 And does it correspond with engine speed or just do it's own thing?

Only at low rpm. When it's up to 3K, the problem pretty much goes away,

especially after running it for a while.

 Never noticed the tach issue before your misfire problem?

Nope, that's the only time it happens, and as I said it doesn't happen
all the time (but it's frustrating when it does).

 SMALL chance it might be on the blink at the same time as whatever is
causing your misfire. Maybe just coincidental.

Don't think so, they're almost surely related, and that's why I'm
leaning twd something electrical rather than the valves or a fuel/carb
related problem.

Another bit of info, the backfire isn't on the overrun--it's when I'm
giving it gas, trying to keep it from stalling.

Rich A

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