Honda-SOHC
SOHC.co.uk Forums => CB500/550 => Topic started by: PennoK3 on October 14, 2024, 11:16:05 AM
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Morning All. Sanity check please I am trying to time a David Silver Electronic Ignition on my CB550 but struggling. Following the instructions and mounting the ignition fully clockwise, then setting the F1.4 mark. Next instruction is "rotate the plate anti clockwise until the LED lights" but it is already lit in the fully clockwise position so there is nowhere to go.
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If you remove the plate from bike is it still lighting the LED ?
In other words, with it remote from any triggering input, does it stay lit ?
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No. If I take it off it goes out.
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OK, so the unit is sensitive to triggering as it should be, that's good.
With it installed, if you rotate the crankshaft, does it then change the LED status ? and if it does, where on the timing marks is it changing ?
Sounds like something simple could be out of place to trigger at wrong point, doesn't sound much but just need to find it.
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It goes out in line with the 2.3 timing mark.
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Unsure of fitment details on this, does it use the original advance and retard mech ?
If so, that can be fitted 180 degree out to give this type effect.
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Yes it does, but all fitted in accordance with the instructions. I'm stumped.
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Can you get a picture up of it ?
There's usually not be much wrong, just spotting what's what to re orientate it correctly.
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The mounting slots don't seem to be equal. The bottom one is against the stop but there is still movement in the others.
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[attachimg=1]
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Presumably, the rotating "collar" mounted onto advance and retard mech has to be assembled and installed ..... that's where you'd be looking for a problem and especially as you can get a trigger effect 180 degree out.
Pull the electronics and dismantle the a&r assembly to see what you've got there.
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Yes checked that. A&R plate correctly mounted on the crank, new ignition rotor is marked with a red dot which is aligned to the TF14 mark on the plate.
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I dont mean to offend but daft question have you got the correct unit ?
There are two different types listed on the DS website iirc, the main plate unit is the same for both but the part that sensor that rotates/fits on the crank is different for the two makes of original points plate.
The smaller i/d unit will not fit on the crank but the larger i/d will fit both but will not locate properly.
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I'm assuming it is the correct unit as I checked over the phone when confirming my order.
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I'm assuming it is the correct unit as I checked over the phone when confirming my order.
Does the sensor fit firmly on the advancer unit is yours a Nippon Denso (ND) unit or the other one (TEC)?
Was the old point base and the advancer unit the same brand it might have been changed in the past easy enough to assume that the brand on the points base is the Electronic Unit you need?
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Yes checked that. A&R plate correctly mounted on the crank, new ignition rotor is marked with a red dot which is aligned to the TF14 mark on the plate.
This would flip the mechanical triggering, any possibility of swapping it by 180 degree to test that way ?
If not, it should run if you swap the coil connections to the wrong way round. It'll have two errors but be corrected to ignite as it should. Not necessarily a solution, but that would prove the error to then understand why that's so.
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Yes, everything fits as it should, all original parts are TEC.
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Then might be as Nigel has said your advancer might be 180 deg out.
Have you had the advancer apart?
Did you originally have the left side CB points connected to the blue wire for cylinders 1 & 4 with the blue wire at the coil end supplying the spark for cylinder1 & 4 plug leads?
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Advancer has not been apart, blue points on the left, yellow points on the right. Blue coil to 1 and 4 plugs.
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I'm not familiar with the DS unit does it need a power supply or is that okay as the red light illuminates.
I've run out of ideas - I assume you have nipped up at least one of the base plates screws to give a good earth.
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Here's a pic of the TEC advancer. Note that the tiny mark in the rim (in white rectangular) should oppose the hole (dito).
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I'm lining it up against the second mark (5 degrees).
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I don’t think the 3 holding bolts are evenly spaced, so maybe if you rotate the pcb board and try the 3 possible positions it could fit you may find a position where the 3 bolts are at the end of the slots with the board in the fully clockwise position. This may then be the correct location for the board and you will be able to time it. Just a guess really but maybe worth a try.
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I'm lining it up against the second mark (5 degrees).
It's the two little white boxes marked onto the mech picture that you need to check.
They are the orientation of the cam timing lobe that controls when it fires. It can be installed 180 degree opposite to that which is correct, then give this fault.
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I don’t think the 3 holding bolts are evenly spaced, so maybe if you rotate the pcb board and try the 3 possible positions it could fit you may find a position where the 3 bolts are at the end of the slots with the board in the fully clockwise position. This may then be the correct location for the board and you will be able to time it. Just a guess really but maybe worth a try.
The board only fits in one position so that the hole in it allows you to view the static timing mark cast into the crankcase.
If it fires (the light changes status here) on the opposite cylinder marking of rotor, then one of three things is wrong.
1) the cam rotor is fitted backwards, as noted in post above. It could already have been installed like that for points, then the two coil wires transposed to correct it on the original installation of this bike. You'd not know as it would run without problem.
2) the board is wrong in its two firing pickup being swapped from manufacturer. Unlikely, but possible.
3)the instructions are written incorrectly with regard to the light showing on or off at the cylinder 1&4 position indicated marks on rotor. Not unknown, have had a ignition product from secondary manufacturer before where they'd transposed the two wiring colours in instruction to make it incorrect, but had everyone involved scratching their head.
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Here's a pic of the TEC advancer. Note that the tiny mark in the rim (in white rectangular) should oppose the hole (dito).
Yes, the orientation of the rotor is as the picture.
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Thanks for all your suggestions so far guys. I'll give it another look this evening.
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OK, found some instructions for installation on t-web :)
Undo the centre small nut, take off the big nut on end of crank ..... now where is the red spot located on the aluminium pulse trigger wheel ?
That spot should be aligned with the "1 & 4" marks of the Honda advance and retard mech. If that's opposite (next to 1&2) then it'll do what it's doing now, that's firing the setup at 180 degree away from intended operation.
I was viewing the manual/instructions for install on the SOHC USA site for reference.
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OK, found some instructions for installation on t-web :)
Undo the centre small nut, take off the big nut on end of crank ..... now where is the red spot located on the aluminium pulse trigger wheel ?
That spot should be aligned with the "1 & 4" marks of the Honda advance and retard mech. If that's opposite (next to 1&2) then it'll do what it's doing now, that's firing the setup at 180 degree away from intended operation.
I was viewing the manual/instructions for install on the SOHC USA site for reference.
Yes the red spot is correctly aligned. I've gone through the installation again today and think I've cracked it through some very careful movement of the electronic board and a combination of completing a full cycle once the LED is lit and positioning with the power off. But it now lights in line with the F1,4 mark and extinguishes after the F 2,3 mark which should be correct. However, in this position there is almost no adjustment left in the bottom right slot on the PCB.
Unfortunately, I can't try a start as I've taken the carbs off to sort a leaky float valve.
Thanks again for all your help and suggestions.