Author Topic: Low throttle hesitation  (Read 7968 times)

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Arizoni

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Reply #15 on: April 05, 2014, 10:48:03 pm
I agree with Scottie.
The engine should be totally grounded and it should make no difference if the test was done between the hot wire and the engine, or the hot wire and the battery negative terminal.

A engine without a direct ground to the battery will still allow the spark plugs to fire but the intensity of the spark will be considerably less.
That's because rather than going directly to ground, the high voltage spark is treating the engine block/cylinder/head as a big capacitor.  In other words, the spark is arcing to the engines mass rather than to ground.

The weak spark produced can cause engine misfires, especially when the engine is under load.

Run a good grounding wire from the ground wire on the battery to any bolt on the engine.  The "head steady" comes to mind as a possible attachment point but if it is used be sure to torque up the fastener to 37 lb/ft (50 N/M).
« Last Edit: April 05, 2014, 10:50:05 pm by Arizoni »
Jim
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gashousegorilla

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Reply #16 on: April 06, 2014, 12:42:52 am
+1   A bad battery ground can cause some odd behavior for sure. You can also check the connection at the battery and at the lug on the starter where it connects. There are both + and - connections on the starter.  I replaced mine with a big old 4 or 6 gauge ground universal ground strap, and trimmed to length.  Also not a bad idea when testing the TPS voltage, to connect to the ground wire on the same plug.... So you know that your ground wire to it is good.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.


KTM_EnfieldRider

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Reply #17 on: April 22, 2014, 02:29:22 am
The problem ended up being a clogged injector. This is frustrating because the authorized repair shop told me they check the injector and it was good. This comes to no surprise because the fuel quality is bad in Nepal.

About the ground issue, I checked again and found good ground on the chrome/bare metal parts of the head (valve covers, spark plug well, etc.) but not on the painted surface of the head. I am no electrician (or mechanic): Is this normal or an indication of an insufficient ground? Everything seems to be working good now.

Thanks for your help.


High On Octane

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Reply #18 on: April 22, 2014, 02:50:47 am
Electrical tests must be performed on bare metal, you will not get a reading when testing on painted parts.  Glad you got it squared away.   :)

Scottie J
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