Commando rebuild help with possible ignition issue

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Hi. Your suggestion promped me to go out into the shed and clean regrease and try again. I also bent the stainless washer a little more to increase the friction.

Tightened the centre screw so I could barely move the choke lever and worked the choke about 5 times. The centre screw is undoing as I work the choke. After 5 cycles the screw is so lose the chokes drop under their spring tension.

However I also went through my box of bits and found an old choke lever. So shall substitute it.

There will be some (many) who will say remove the chokes completely but I have been down that road and my bike likes the choke on a cool day.

Thinking this through there is clearly an issue with this lever. The screw should sit down on the upper section and clamp it to the lower piece. Leaving a gap for the lever to move between the upper and lower parts damped by the friction of the spring washer. The lever action is undoing the screw therefore it must be contacting the upper section.

I'm going to have to pull it apart again and inspect it more closely.

Sorry to somewhat sideline this thread but the choke may actually still be the OPs problem.
You are not alone. I spent a ridiculous amount of time fiddling with one of those Far Eastern pieces of crap a while ago. I ended up using the ‘elastic band to keep it open’ method until I managed to find a decent original which worked perfectly.
 
I use a bit of Wellseal on the choke pivot screw thread but sparingly.
 
To throw another suggestion in, based on personal experience:

One of mine, just rebuilt from the ground up - and with the Air Slides fully open - wouldn't rev beyond 3-4k and replacing the Ignition module made no difference.
It was just like hitting a rev limiter, and after much checking of wiring, ignition switch and everything else to no effect I concluded that it must be fuel related.
Replacing the throttle needles and jets did the trick.
I'd never appreciated how worn components in the carb could have such a profound effect. Cheap fix too, not counting the hours I spent getting there!

I've used the replica combined brake/air lever assemblies and haven't had any issues at all - perhaps I was lucky?
 
You are not alone. I spent a ridiculous amount of time fiddling with one of those Far Eastern pieces of crap a while ago. I ended up using the ‘elastic band to keep it open’ method until I managed to find a decent original which worked perfectly.
Mmmmm. Seems I may be beating a dead horse.

Thanks for this info.
 
I have found that the choke levers sold these days seem to slowly move and close the choke unless they are screwed down so tight that they basically cannot be moved with fingers.

So either you have a choke you can adjust to start the bike but it keeps moving closed over an hour or so running.

Or it's so tight it can't be used.

I have yet to solve ths issue.
Fast Eddie said:
I ended up using the ‘elastic band to keep it open’

It’s been a problem forever.
I commonly saw air levers held open by rubber loops cut from inner tubes, back in the good old days of stormcoat and waders.
 
Mmmmm. Seems I may be beating a dead horse.

Thanks for this info.
Actually, the real end of my story is that after all that faffing around, I took the chokes out !

This was on my ‘68 T120 with Premier‘s. Once I’d corrected the pilot jet, and set it up fairly well, it just didn’t need chokes really, so I was quite pleased to remove such a troublesome and flawed piece of engineering !
 
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Another thing with choke levers is when parked anywhere people just can't help themselves and will move the lever so the chokes drop down and riding off without noticing it till it starts to play up, been there done that so haven't had chokes on my Norton now for 43 years, as others have said riding with the chokes closed will cause your running problems, lever on the slack the chokes are down.
 
I have found that the choke levers sold these days seem to slowly move and close the choke unless they are screwed down so tight that they basically cannot be moved with fingers.

So either you have a choke you can adjust to start the bike but it keeps moving closed over an hour or so running.

Or it's so tight it can't be used.

I have yet to solve this issue.
I found that careful routing of the choke cables and greasing the splitter made a big difference in the amount of force needed to move the lever. And as an FYI, a US 25 cent piece fits the slot nicely.
 
I found that careful routing of the choke cables and greasing the splitter made a big difference in the amount of force needed to move the lever. And as an FYI, a US 25 cent piece fits the slot nicely.
Unlike with other cables on the bike, doing diligent work like that is actually counter productive to the issue here. Super smooth / free cables will allow more of the choke flap spring pressure to act on the lever. Stiff cables will mean that some of that spring pressure is absorbed by the cable etc.
 
Unlike with other cables on the bike, doing diligent work like that is actually counter productive to the issue here. Super smooth / free cables will allow more of the choke flap spring pressure to act on the lever. Stiff cables will mean that some of that spring pressure is absorbed by the cable etc.
I think differently - having smooth action on the slides makes it possible to adjust lever tension precisely with the lever tension screw.
 
I think differently - having smooth action on the slides makes it possible to adjust lever tension precisely with the lever tension screw.
No argument there.

My point is only that these cables, unlike any other on the bike, are really holding against a force rather than pulling on a force to actuate / operate. So a little stiction will actually help, especially if you’ve got an unhelpful lever assembly (as some do).
 
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Thanks everyone for the replies!!! I’m happy to report Turns out it was just the choke after all.
That’s great!

And if you hadn’t learnt it before, you surely have now - always, always, always, check the simplest stuff first!

I don’t know why, but that just doesn’t come naturally to us motorcycle types, we’ve all been there before, stripping stuff down that doesn‘t need stripping!

My personal best was stripping a carb cos of a running issue… and noticing that the fuel petcock was turned on… and even though I’d got the float bowl off, there was no fuel coming out… yup, I’d got a dry tank !!
 
That’s great!

And if you hadn’t learnt it before, you surely have now - always, always, always, check the simplest stuff first!

I don’t know why, but that just doesn’t come naturally to us motorcycle types, we’ve all been there before, stripping stuff down that doesn‘t need stripping!

My personal best was stripping a carb cos of a running issue… and noticing that the fuel petcock was turned on… and even though I’d got the float bowl off, there was no fuel coming out… yup, I’d got a dry tank !!
Yeah for sure… although that would have been still very low on my list of things to check as I would not have thought the choke would cause those symptoms I would have thought it would run poorly. I’m very glad I came an asked for advice here because I would have probably been beating my head against the wall for awhile haha. Hey and I’ve gained more knowledge so it’s been a win win for me
 
Yeah for sure… although that would have been still very low on my list of things to check as I would not have thought the choke would cause those symptoms I would have thought it would run poorly. I’m very glad I came an asked for advice here because I would have probably been beating my head against the wall for awhile haha. Hey and I’ve gained more knowledge so it’s been a win win for me
Good to hear resolved. Regarding your question on using Typanium Reg/Rec, generally these are known to be electrically noisey. They are fine for running points ign systems, but when you start going to modern/digital systems, e-noise becomes critical. TriSpark has a bulletin on their website about e-noise from Podtronics R/R's causing misfires on the digital Trispark ign setup.
 
Good to hear resolved. Regarding your question on using Typanium Reg/Rec, generally these are known to be electrically noisey. They are fine for running points ign systems, but when you start going to modern/digital systems, e-noise becomes critical. TriSpark has a bulletin on their website about e-noise from Podtronics R/R's causing misfires on the digital Trispark ign setup.
Yeah I seen TriSpark’s bulletin about Podtronics R/R and wasn’t sure if the Tympanium was the same. Thanks for clearing that up for me.
 
Toronado writes: "Regarding your question on using Typanium Reg/Rec, generally these are known to be electrically noisey".

I found a number of posts related to the Podtronics 200 watt regulator rectifier of recent vintage being a problem (too noisy) for a Tri-spark ignitions. I have not heard this to be true with the Tympanium.
 
Toronado writes: "Regarding your question on using Typanium Reg/Rec, generally these are known to be electrically noisey".

I found a number of posts related to the Podtronics 200 watt regulator rectifier of recent vintage being a problem (too noisy) for a Tri-spark ignitions. I have not heard this to be true with the Tympanium.
True, but the Typanium is not something that would/should likely have any sort of noise suppression. It is a product that came out in the days of points/analog igns. I've also heard it mentioned as noisy in an article on all the different R/R's noise issues.
 
Good to hear resolved. Regarding your question on using Typanium Reg/Rec, generally these are known to be electrically noisey. They are fine for running points ign systems, but when you start going to modern/digital systems, e-noise becomes critical. TriSpark has a bulletin on their website about e-noise from Podtronics R/R's causing misfires on the digital Trispark ign setup.

But is the Tri Spark R/R in the same ballpark as the Shindengen MOSFET wise.
I am still sitting on the fence about getting one of these (TS) to replace the new Podtronic's.

From Tri Spark.
MOSFET. ($165)
"These voltage regulators use the latest MOSFET technology for cool running reliability. Unlike the previous generation of regulators that waste power and run hot these MOSFET regulators will impress the most discerning buyer."

Followed by this which seems to be the above.

$95.
"Podtronics Three Phase Voltage Regulator for 12 volt electrical systems. This replaces the stock rectifier and zener diode. Suits Triumph BSA and Norton machines with three phase alternators. Rated for 240 Watts max. Size 75 x 80 x 30mm approx.

If they 'waste power and run hot, why sell them, for the non discerning buyer perhaps. :D

I would like an electrical savvy person to say, the more expensive unit is worth buying (long term)
 
But is the Tri Spark R/R in the same ballpark as the Shindengen MOSFET wise.
I am still sitting on the fence about getting one of these (TS) to replace the new Podtronic's.

From Tri Spark.
MOSFET. ($165)
"These voltage regulators use the latest MOSFET technology for cool running reliability. Unlike the previous generation of regulators that waste power and run hot these MOSFET regulators will impress the most discerning buyer."

Followed by this which seems to be the above.

$95.
"Podtronics Three Phase Voltage Regulator for 12 volt electrical systems. This replaces the stock rectifier and zener diode. Suits Triumph BSA and Norton machines with three phase alternators. Rated for 240 Watts max. Size 75 x 80 x 30mm approx.

If they 'waste power and run hot, why sell them, for the non discerning buyer perhaps. :D

I would like an electrical savvy person to say, the more expensive unit is worth buying (long term)
My quoted post did not say anything about the Trispark R/R, was about the simple Typanium unit, which is basically an AC to DC converter with voltage regulation....no added suppression circuitry etc...dirt cheap, fine for points or most analog e-igns. Trispark R/R is MOSFET design so runs cooler, more efficiently like the shunting types (including Typanium). It also has built in noise suppression, (either by virtue of the MOSFET design or added suppression circuitry or both).
 
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