Ok - so - the Ltd continues to tax me grey cells.
The bit I'm struggling to understand is the ignition advance side of things.
Spec - full rebuild 1k mile B1 Ltd running Dyna S - direct powered 3ohm coils - resistor leads - 1045 wiseco 1025 comp - dialed standard cams/valves - 26ss carbs re-jetted for the VH pipe - good replacement starter with much cranking foo.
So - set up the bike to the maximum advance line at 3500rpm and once running the bike runs strong and behaves well all the way through the rev range - no stuttering - spot on smooth idle - nigh on perfect.
Err - No! - hot or cold the starter struggles to turn if it doesn't catch more or less straight away - kick starting is difficult but possible - it's as if there is too much advance?
Tried new springs on the advancer which made things worse.
When using a strobe it starts at the 'F' mark on tick-over and advances up gradually till it gets to the maximum line.
So - retard it 1° to just inside the advance line - starts a little easier - stutters just a touch in the midrange when cold - looses a little top end grunt when hot - liveable but not perfect.
Retard it further say 2.5° - starts on the button - but runs like a sack of shite spluttering everywhere bar a rough(ish) 1k rpm idle!
Adding a battery booster pack makes no difference, so it's not lack of battery power.
Jamming a spanner across the solenoid makes no difference, so it's not the solenoid.
Have tried a good 4 brush 1000J starter motor which made no difference, so not the starter.
I've considered the raised compression ratio to be not helping.
The programmable Dyna 2000 could be used to gain a retarded start position - but is a tad pricy as a solution.
Weaker advance springs?
Somehow increase the advance range?
Retard and re-jet?
Could the resistor leads be not helping?
Is this common with Dyna ignitions?
Petrol and matches?
Any opinions?
Hello Guest User,
Please feel free to have a look around the forum but be aware that as an unregistered guest you can't see all of it and you can't post.
To access these 'Registered Users Only' areas simply register and login.
Please feel free to have a look around the forum but be aware that as an unregistered guest you can't see all of it and you can't post.
To access these 'Registered Users Only' areas simply register and login.
Advance Damit..
Moderators: KeithZ1R, chrisu, paul doran, Taffus
Have you got the correct advance range unit?
Has it got the thin shim behind the new DYNA rotor?
If yes or if its damaged take it out. They jam the rotor.
Has it got the 'wiper' damper tabs on the bob weights or have they fallen off?
They are small rectangular pads at the ends of the bob weights (inner edge) that run up against the rotor base.
If they are missing it will end up with the wrong advance curve!!
Have you got the correct clearance between the pickups and the rotor magnet at the point of firing?
25 thou from memory but it is critical.
Has it got full 13 volts?
If it does not then the lazy voltage reads either the back or the front of the magnet as it passes and gives a different point of ignition that that set.
Sometimes reads back and front and initiates twin firing!
Did it achieve more advance than the 'set line' if you revved it higher than 3500 RPM??
I seriously doubt that poor running will be attributable to retarding by 1 degree so it sounds like something else is going on there.
I think that they prefer silicone leads and probably not resistor types if possible.
Did you have to elongate the holes in the backplate to get to the correct static timing value?
AL
Has it got the thin shim behind the new DYNA rotor?
If yes or if its damaged take it out. They jam the rotor.
Has it got the 'wiper' damper tabs on the bob weights or have they fallen off?
They are small rectangular pads at the ends of the bob weights (inner edge) that run up against the rotor base.
If they are missing it will end up with the wrong advance curve!!
Have you got the correct clearance between the pickups and the rotor magnet at the point of firing?
25 thou from memory but it is critical.
Has it got full 13 volts?
If it does not then the lazy voltage reads either the back or the front of the magnet as it passes and gives a different point of ignition that that set.
Sometimes reads back and front and initiates twin firing!
Did it achieve more advance than the 'set line' if you revved it higher than 3500 RPM??
I seriously doubt that poor running will be attributable to retarding by 1 degree so it sounds like something else is going on there.
I think that they prefer silicone leads and probably not resistor types if possible.
Did you have to elongate the holes in the backplate to get to the correct static timing value?
AL
1981 J1
zorded wrote:Have you got the correct advance range unit?
Yes I think so - not the early type.
Has it got the thin shim behind the new DYNA rotor?
If yes or if its damaged take it out. They jam the rotor.
No removed it when I realized the advance wasn't working.
Has it got the 'wiper' damper tabs on the bob weights or have they fallen off?
They are small rectangular pads at the ends of the bob weights (inner edge) that run up against the rotor base.
If they are missing it will end up with the wrong advance curve!!
All present and correct.
Have you got the correct clearance between the pickups and the rotor magnet at the point of firing?
25 thou from memory but it is critical.
sort of - see below
Has it got full 13 volts?
Yes - live battery voltage.
If it does not then the lazy voltage reads either the back or the front of the magnet as it passes and gives a different point of ignition that that set.
Sometimes reads back and front and initiates twin firing!
Yes - it does that see below.
Did it achieve more advance than the 'set line' if you revved it higher than 3500 RPM??
No - never past the line.
I seriously doubt that poor running will be attributable to retarding by 1 degree so it sounds like something else is going on there.
So do I - hence the question.
I think that they prefer silicone leads and probably not resistor types if possible.
Got a set of Taylor leads I'm going to try.
Did you have to elongate the holes in the backplate to get to the correct static timing value?
Yes initially - but now pulled back from that point.
AL
OK - So - I think you have something there - the penny slowly begins to drop!
The Ghosting, Double Firing - I didn't think to mention that - but now you mention it - the ghosting has been there from the start - not all the time - but there none the less - I thought it was my ancient timing light that has since died - never noticed but the new one does it to!
Progress!
I've checked the voltage to the pick-ups and get live battery voltage, get it even when hooked up to the battery booster pack - hit the start button and it drops to 12v until the start button is released.
The relay feed comes from the battery connection at the solenoid, the coil and dyna feed comes via the relay, the relay is triggered by the kill switch and goes to battery earth.
The battery has two 16mm cable earths, one to the motor upper case and main loom connection and one to the starter motor mount bolt.
Pick-up clearance:
2-3 pick-up as found was 0.6mm of clearance.
1-4 pick-up as found was 1.2mm of clearance.
There was very little movement in the 1-4 pick-up channels so I opened them out to get extra movement - ghosting is only apparent on the 1-4 pick up - move the sensor in to 0.6mm clearance and the ghosting gets to the point it's triggering more so on the ghost side - the timing light picks out the spring mount on the advancer more! but at no position is it only one side all the time - bugger! poor connection somewhere perhaps? or duff pick-up?
Will try swapping the coils round.
I opened out the channels to move the 2-3 sensor further towards the magnet or move it further away - when moved in or out there is no ghosting but the trigger fails to be regular and a misfire develops - Mmmmm!
Both at 0.6mm clearance and there is not enough adjustment in the sensor slots to make them anything like a pair - bugger.
So - something is beginning to make sense.
If the ghosting gets worse with low battery voltage - then it's firing occasionally on the other side of the magnet - but wouldn't that make it retarded - not advanced?
More experiments are necessary I think.
Thanks for the info - much appreciated.
Just a suggestion.
If your starter is lazy its worth doing a drop test on the main wiring feed and the earth.
If you have high resistance in the positive to the starter or the earth return to the battery you are burning amps in the wiring.
Put voltmeter wires at each ernd of the positive from battery to solenoid. crank the engine and check that the voltage on the meter stays low.
Do the same between the solenoid and the starter motor , and then between the engine and battery earth.
If you get a voltage showing when cranking you have high resistance in the wiring.
See
http://www.aa1car.com/library/voltage_drop_testing.htm
If your starter is lazy its worth doing a drop test on the main wiring feed and the earth.
If you have high resistance in the positive to the starter or the earth return to the battery you are burning amps in the wiring.
Put voltmeter wires at each ernd of the positive from battery to solenoid. crank the engine and check that the voltage on the meter stays low.
Do the same between the solenoid and the starter motor , and then between the engine and battery earth.
If you get a voltage showing when cranking you have high resistance in the wiring.
See
http://www.aa1car.com/library/voltage_drop_testing.htm
member number 0664
Who can catch a Kawasaki?
A police helicopter
Who can catch a Kawasaki?
A police helicopter
In case youve not got them.
Even the best quality strobe will struggle to give a steady reading.
Was always told to use an external battery and not the one on the vehicle being tested!
25 to 40 thou is correct for magnet proximity.
Reading youre project thread; you mentioned changing leads / changing carbs and synchronising the pick-ups!
Yes i think it is important where you get youre 12 volts from!
At that point i will stop talking about electrics because it is something i really dont understand.
On the subject of rough running and loss of urge higher up; with 26mm carbs and a V&H i could imagine it running borderline weak even if up-jetted a little.
Previous retarding of ignition to help with starting will have exaggerated this condition if it does exist.
Not specifically an ignition problem but more of a composite of circumstances perhaps?
Yes 2000 would help and you can set a retard programme or manually / mechanically invoke one but as you say; an expensive way to fix a small problem.
The DYNA 'S' is basically bomb proof and very very effective. Once it is sorted out it is near perfect.
Finally; can you say whether the advance retard unit is spinning concentrically?
Mine was off by some way and it was caused by the drive peg (dowel) which has been replaced.
It must have a taper to the outside, mine didn't!!!
AL
Even the best quality strobe will struggle to give a steady reading.
Was always told to use an external battery and not the one on the vehicle being tested!
25 to 40 thou is correct for magnet proximity.
Reading youre project thread; you mentioned changing leads / changing carbs and synchronising the pick-ups!
Yes i think it is important where you get youre 12 volts from!
At that point i will stop talking about electrics because it is something i really dont understand.
On the subject of rough running and loss of urge higher up; with 26mm carbs and a V&H i could imagine it running borderline weak even if up-jetted a little.
Previous retarding of ignition to help with starting will have exaggerated this condition if it does exist.
Not specifically an ignition problem but more of a composite of circumstances perhaps?
Yes 2000 would help and you can set a retard programme or manually / mechanically invoke one but as you say; an expensive way to fix a small problem.
The DYNA 'S' is basically bomb proof and very very effective. Once it is sorted out it is near perfect.
Finally; can you say whether the advance retard unit is spinning concentrically?
Mine was off by some way and it was caused by the drive peg (dowel) which has been replaced.
It must have a taper to the outside, mine didn't!!!
AL
1981 J1
Oldzed - Excellent.
I had been pondering the cabling, hence adding the extra earth to the starter, which has made no appreciable difference.
It makes good sense to test the rest, all cabling was new 18 months ago - but that guarantees nothing.
The original re-built starter motor had fried the wires and worn the brushes in a thousand miles - I put that down to cheap brushes, but I'm starting to think there may be another reason.
I was surprised the four brush starter didn't increase cranking speed, high cable resistance would be an obvious answer.
Zorded - great stuff, not got that info.
Yes I use a separate battery for the light, I too fear there may be more than one issue at play here - Oldzed has pointed to another sound possibility that I had not taken seriously enough.
The motor is basically A1 in set up, as it came from one, the crank dowel is new, the TDC mark in the casting is off approx 1mm as I found out when dialling in the cams so I allow for this.
There is no eccentric movement in the rotor that I can detect it seems to run true.
Carb setup was interesting, once the timing has been put to bed I will review it.
Thanks guys - much appreciated.
More testing.....
I had been pondering the cabling, hence adding the extra earth to the starter, which has made no appreciable difference.
It makes good sense to test the rest, all cabling was new 18 months ago - but that guarantees nothing.
The original re-built starter motor had fried the wires and worn the brushes in a thousand miles - I put that down to cheap brushes, but I'm starting to think there may be another reason.
I was surprised the four brush starter didn't increase cranking speed, high cable resistance would be an obvious answer.
Zorded - great stuff, not got that info.
Yes I use a separate battery for the light, I too fear there may be more than one issue at play here - Oldzed has pointed to another sound possibility that I had not taken seriously enough.
The motor is basically A1 in set up, as it came from one, the crank dowel is new, the TDC mark in the casting is off approx 1mm as I found out when dialling in the cams so I allow for this.
There is no eccentric movement in the rotor that I can detect it seems to run true.
Carb setup was interesting, once the timing has been put to bed I will review it.
Thanks guys - much appreciated.
More testing.....
A bike of mine did this when i fitted dyna s once.
It was the dyna rotor sticking, took the thin shim out and it still did it, ended up taking some off the rotor with fine wet and dry on a piece of glass. Make sure you can turn the rotor freely with your fingers and feel the advance unit working smoothly. Been spot on since
It was the dyna rotor sticking, took the thin shim out and it still did it, ended up taking some off the rotor with fine wet and dry on a piece of glass. Make sure you can turn the rotor freely with your fingers and feel the advance unit working smoothly. Been spot on since
TDC set, no shim, wiring was all new and good.
Have so far found no change when direct powering dyna with a separate battery, still ghosting.
Resistance is high on the battery live to solenoid, will replace that first.
Slight resistance on coil/dyna feed from relay, will replace and change relay just to be sure.
Changing to Taylor leads and coil checks, plugs look great but will be changed anyway - one less thing to worry about.
Making progress.
Have so far found no change when direct powering dyna with a separate battery, still ghosting.
Resistance is high on the battery live to solenoid, will replace that first.
Slight resistance on coil/dyna feed from relay, will replace and change relay just to be sure.
Changing to Taylor leads and coil checks, plugs look great but will be changed anyway - one less thing to worry about.
Making progress.
Full day on this today.
Cables first.
Big difference between just ign on and motor running when doing the multimeter bypass test as suggested by oldzed.
Batt + to solenoid 2.95v difference was shown on multimeter with old wire 0.57v on new wire.
Solenoid to starter 0.62v so left as found.
Crankcase to Batt- was 3.6v as found 1.5v with new wire.
Result - no real change in cranking performance - no change in ghosting.
Changed power feed wire to coils and dyna, no change.
Swapped plug leads to Taylor ones and fitted new plugs - no change.
Tested the dyna coils and pick-ups and was unable to get anything like the readings on the charts - I can believe one coil could go bad - but two is just not cricket!
Primary resistance came up as infinite on 1-4 coil and 0.3 ohms on 2-3 coil - secondary was 6.67 on 1-4 and 10.2 on 2-3.
Dyna triggers were switching fine, it happens 1-4 was fine with the larger gap, 2-3 was fine with the smaller gap - so the triggers were working to spec - the ghosting was to do with the coils - I swapped the coils round and the ghosting changed to 2-3.
Changed back to points and pattern coils, ladies and gentlemen we have a winner.....
Although the starter is still sluggish there is no trying to turn the starter back going on anymore - after a brief road test I concluded she has her mojo back
So at least I know half the problem, the sluggish starter still needs more investigation.
Thanks for the help guys
Cables first.
Big difference between just ign on and motor running when doing the multimeter bypass test as suggested by oldzed.
Batt + to solenoid 2.95v difference was shown on multimeter with old wire 0.57v on new wire.
Solenoid to starter 0.62v so left as found.
Crankcase to Batt- was 3.6v as found 1.5v with new wire.
Result - no real change in cranking performance - no change in ghosting.
Changed power feed wire to coils and dyna, no change.
Swapped plug leads to Taylor ones and fitted new plugs - no change.
Tested the dyna coils and pick-ups and was unable to get anything like the readings on the charts - I can believe one coil could go bad - but two is just not cricket!
Primary resistance came up as infinite on 1-4 coil and 0.3 ohms on 2-3 coil - secondary was 6.67 on 1-4 and 10.2 on 2-3.
Dyna triggers were switching fine, it happens 1-4 was fine with the larger gap, 2-3 was fine with the smaller gap - so the triggers were working to spec - the ghosting was to do with the coils - I swapped the coils round and the ghosting changed to 2-3.
Changed back to points and pattern coils, ladies and gentlemen we have a winner.....
Although the starter is still sluggish there is no trying to turn the starter back going on anymore - after a brief road test I concluded she has her mojo back
So at least I know half the problem, the sluggish starter still needs more investigation.
Thanks for the help guys
Charge voltage is around 13.25-13.5volts at 1k rpm idle up to a maximum of 14.5volts at 4.5k rpm upwards.
I jammed a spanner across the solenoid - made no difference.
When I have time I'm pulling the alt side cover to check nothing is binding on the casing or gears when cranking - not that it's making any nasty noises but just to be sure.
Drained the carbs and took the plugs out, it spins over fine - very freely - which is to be expected - only slows down when you give the starter something to push against.
The same is true if you crank it with a spanner - turns very easily and smoothly but as I would expect each time I replace a plug it gets progressively harder to turn - nothing out of the ordinary - more compression than my 900 but not masses more - nothing like as much as my Tuono!
I jammed a spanner across the solenoid - made no difference.
When I have time I'm pulling the alt side cover to check nothing is binding on the casing or gears when cranking - not that it's making any nasty noises but just to be sure.
Drained the carbs and took the plugs out, it spins over fine - very freely - which is to be expected - only slows down when you give the starter something to push against.
The same is true if you crank it with a spanner - turns very easily and smoothly but as I would expect each time I replace a plug it gets progressively harder to turn - nothing out of the ordinary - more compression than my 900 but not masses more - nothing like as much as my Tuono!
Who is online
Users browsing this forum: No registered users and 14 guests