running like crap - 2000-3000 RPM - a bit stumped and not sure where to go

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joe czech

joe czech

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i've been fighting this issue, on and off for a couple months now. seems like i have an engine problem between 2000 and 3000 RPM. happens with any gear - above 3K, seems to smooth out and appears to be running normal. idle's good, around 1100-1200 RPM. best i can tell one or both cylinders are cutting out. lots of bucking, shaking , and exhaust popping. i pulled the tops of the carbs to check needles and slides. ditto on the bottom - dropped the float bowls - checked jets, floats, etc., found nothing abnormal. there was several threads on compatibility issues with podtronics and tri-spark assemblies (have both), but that problem occurs between 3000 and 4000 rpm, not the 2-3000 range. anyway, tri-spark indicated to disconnect the alternator stator wires as part of the trouble shooting procedure - did that - no change. not sure where to go from here, so looking for a little advice. whatever it is, seems to me to be an RPM related issue. BTW, the norton's equipped with an alton e-starter, and running their stator assembly. up to a couple months ago, it was running like a top, and since this started, seems to be getting worse with each ride. don't have vast experience on these old twins but i don't think it's carb related, but leaning toward electrical and and maybe frequency dependent. need some help and comments. TIA....
 
What do the plugs look like?

Really bad gas. Out of sync carburetion. EMI. Loose wire connection. Bad float needle. Float with a hole in it.

Just giving you a bump.
 
Had similar troubles several years ago , was cracked wire on Boyer pickup ... so doubtful that is any help .... good luck !
As Cliff suggested make sure battery connection is clean and tight as well ...
 
joe czech said:
i've been fighting this issue, on and off for a couple months now. seems like i have an engine problem between 2000 and 3000 RPM. happens with any gear - above 3K, seems to smooth out and appears to be running normal. idle's good, around 1100-1200 RPM. best i can tell one or both cylinders are cutting out. lots of bucking, shaking , and exhaust popping. i pulled the tops of the carbs to check needles and slides. ditto on the bottom - dropped the float bowls - checked jets, floats, etc., found nothing abnormal. there was several threads on compatibility issues with podtronics and tri-spark assemblies (have both), but that problem occurs between 3000 and 4000 rpm, not the 2-3000 range. anyway, tri-spark indicated to disconnect the alternator stator wires as part of the trouble shooting procedure - did that - no change. not sure where to go from here, so looking for a little advice. whatever it is, seems to me to be an RPM related issue. BTW, the norton's equipped with an alton e-starter, and running their stator assembly. up to a couple months ago, it was running like a top, and since this started, seems to be getting worse with each ride. don't have vast experience on these old twins but i don't think it's carb related, but leaning toward electrical and and maybe frequency dependent. need some help and comments. TIA....
Click to expand...
If you rev it at a stand still with a hand near each silencer outlet in turn, can you detect it missing on one cylinder or both?
 
It may be worth testing the Pod to see if it is all good. And this way you redo the connections anyway if it is.

Copied this from a guests post, and it helped me identify a bad Pod

First test the rectifier circuits.

The regulator/rectifier must be disconnected from everything on the bike.

Set your multimeter to continuity or resistance (when you cross the positive and negative leads, your meter will beep or read zero)

Test One
  • Attach your red multimeter lead to the red lead of the regulator/rectifier
  • Attach the black multimeter lead to one of the yellow leads of the regulator/rectifier
  • Your multimeter should not beep, or give any reading
  • Do the same for the second yellow lead (and third if you are testing a three phase unit)

Test Two
  • Attach your black multimeter lead to the red lead of the regulator/rectifier
  • Attach the red multimeter lead to one of the yellow leads of the regulator/rectifier
  • Your multimeter should beep, or give a reading - write down the value on a piece of paper
  • Do the same for the second yellow lead (and third if you are testing a three phase unit) write down the value each time

Test Three
  • Attach your black multimeter lead to the black lead of the regulator/rectifier
  • Attach the red multimeter lead to one of the yellow leads of the regulator/rectifier
  • Your multimeter should not beep, or give any reading
  • Do the same for the second yellow lead (and third if you are testing a three phase unit)

Test Four
  • Attach your red multimeter lead to the black lead of the regulator/rectifier
  • Attach the black multimeter lead to one of the yellow leads of the regulator/rectifier
  • Your multimeter should beep, or give a reading - write down the value on a piece of paper
  • Do the same for the second yellow lead (and third if you are testing a three phase unit) write down the value each time

All of the values above zero that you have written down should be more or less the same.

If there are any wildly different numbers, it signifies a fault with one of the diodes. This is not serviceable, do the unit must be thrown away.



Now test the regulator circuit.

This should be done on the bike, with everything connected - no easy bench tests without more advanced test kit I’m afraid.

You need to have a good battery attached, as the regulator/rectifier will not give a steady output on it’s own, and the battery will smooth out your measurements, making it easier to see what’s going on.

Set your multimeter to DC volts, put the red lead on the battery positive terminal, and the black lead on the battery negative terminal.

  • With your engine switched off, and no consumers like coil or lights drawing any power you will see around 12 to 13 volts (varies depending on the type of battery you have)
Lead acid (including gel, AGM, flooded and drycell) are 2.1 volts per cell, so you should see 12.6 volts at rest

Lithium based (including lithium-ion, lithium polymer, LiCoO2, lithium cobalt oxide and LiFePO4) are 3.6 volts per cell, so you should see 14.4 volts at rest

  • Start your engine and let it idle.
You should see the voltage at the battery drop to around 11 to 12 volts

This shows that you are drawing more out than you are putting in - absolutely normal for the charging system of this era, and one of the reasons that the three phase alternator came along at a later date

  • Now hold your revs at an RPM of three to four thousand
You should see the voltage reading on your multimeter go up to around 14 to 15 volts

Hope this helps!
 
Put the Tri-Spark VR-0030 regulator/rectifier on it while you are troubleshooting. It's a much better product than the PODtronics regulator/rectifier, uses larger gauge sheathed wire, runs cooler, and it's smaller. I just got one. No comparison. Talk to Greg Marsh marshg246 about purchase.

If that doesn't help, the battery could be going south.
 
THANKS FOR ALL THE RESPONSES - plenty of things to check out. my gut feeling is centering around the podtronic unit - plan is to install my original (lucas) rectifier and Zener, and give all wiring connections a good look over. been thinking about replacing the podtronics anyway, so this may be a good time for an upgrade. again, thanks....
 
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concours said:
In that case, use a jumper wire from the battery to supply the TriSpark. I fixed one of those on the side of the road too.
Click to expand...
Electronic ingition?
Could be battery unable to hold charge, but this usually results in misfire at lower revs too.
When revved above 3K the sator is providing enough charge for ingition.
 
gortnipper said:
It may be worth testing the Pod to see if it is all good. And this way you redo the connections anyway if it is.

Copied this from a guests post, and it helped me identify a bad Pod

First test the rectifier circuits.

The regulator/rectifier must be disconnected from everything on the bike.

Set your multimeter to continuity or resistance (when you cross the positive and negative leads, your meter will beep or read zero)

Test One
  • Attach your red multimeter lead to the red lead of the regulator/rectifier
  • Attach the black multimeter lead to one of the yellow leads of the regulator/rectifier
  • Your multimeter should not beep, or give any reading
  • Do the same for the second yellow lead (and third if you are testing a three phase unit)

Test Two
  • Attach your black multimeter lead to the red lead of the regulator/rectifier
  • Attach the red multimeter lead to one of the yellow leads of the regulator/rectifier
  • Your multimeter should beep, or give a reading - write down the value on a piece of paper
  • Do the same for the second yellow lead (and third if you are testing a three phase unit) write down the value each time

Test Three
  • Attach your black multimeter lead to the black lead of the regulator/rectifier
  • Attach the red multimeter lead to one of the yellow leads of the regulator/rectifier
  • Your multimeter should not beep, or give any reading
  • Do the same for the second yellow lead (and third if you are testing a three phase unit)

Test Four
  • Attach your red multimeter lead to the black lead of the regulator/rectifier
  • Attach the black multimeter lead to one of the yellow leads of the regulator/rectifier
  • Your multimeter should beep, or give a reading - write down the value on a piece of paper
  • Do the same for the second yellow lead (and third if you are testing a three phase unit) write down the value each time

All of the values above zero that you have written down should be more or less the same.

If there are any wildly different numbers, it signifies a fault with one of the diodes. This is not serviceable, do the unit must be thrown away.



Now test the regulator circuit.

This should be done on the bike, with everything connected - no easy bench tests without more advanced test kit I’m afraid.

You need to have a good battery attached, as the regulator/rectifier will not give a steady output on it’s own, and the battery will smooth out your measurements, making it easier to see what’s going on.

Set your multimeter to DC volts, put the red lead on the battery positive terminal, and the black lead on the battery negative terminal.

  • With your engine switched off, and no consumers like coil or lights drawing any power you will see around 12 to 13 volts (varies depending on the type of battery you have)
Lead acid (including gel, AGM, flooded and drycell) are 2.1 volts per cell, so you should see 12.6 volts at rest

Lithium based (including lithium-ion, lithium polymer, LiCoO2, lithium cobalt oxide and LiFePO4) are 3.6 volts per cell, so you should see 14.4 volts at rest

  • Start your engine and let it idle.
You should see the voltage at the battery drop to around 11 to 12 volts

This shows that you are drawing more out than you are putting in - absolutely normal for the charging system of this era, and one of the reasons that the three phase alternator came along at a later date

  • Now hold your revs at an RPM of three to four thousand
You should see the voltage reading on your multimeter go up to around 14 to 15 volts

Hope this helps!
Click to expand...
Very helpful
 
Bernhard said:
Electronic ingition?
Could be battery unable to hold charge, but this usually results in misfire at lower revs too.
When revved above 3K the sator is providing enough charge for ingition.
Click to expand...
The TriSpark gets its ground from the engine, via a terminal screwed under one of the points cover pillars. The stock engine ground is from the harness through the head steady. If that connection is flaky under vibration the ignition will be very unhappy.
 
maylar said:
The TriSpark gets its ground from the engine, via a terminal screwed under one of the points cover pillars. The stock engine ground is from the harness through the head steady. If that connection is flaky under vibration the ignition will be very unhappy.
Click to expand...
Or, something simple as the ignition switch having a loose wire, but that has been addressed by Concours suggesting a hot wire from the battery.

Slick
 
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