Changing HT leads

[beardylondon]

Hi All,

I have seen this discussed before, and it know it's not straightforward, as they are hard wired into the coil.

Is there a guide to replacing the HT leads? Mine are pretty knackered, so want to sort it out, preferably myself.

Bike is '76 550, import.

cheers.

[Nurse Julie]

http://info.sohc.co.uk/download/ashs-ignition-coil-fix-2/

[beardylondon]

Thanks very much!

[beardylondon]

next question, if mine need replacing, I note the TEC ones at £70 per side, are the aftermarket ones any good?

https://www.davidsilverspares.co.uk/CB550K-1976-USA/part_83533/

[McCabe-Thiele (Ted)]

Not sure I thought someone here said the DS coils are same make as Honda's TEC?

[Seabeowner]

You can get away with cutting out a much smaller section than that described in Ash's file. It's more tricky as you don't want to sever the secondary fine wire, but can be done. The lead that goes a long way through the potting can be pulled through once it is unsoldered. Use a thin wire soldered (temporarily) to the new wire to pull back through.

[beardylondon]

even cheaper here:

https://www.squaremotorcycleparts.co.uk/products/ignition-coil-x2-honda-cb550-cb-550-1974-1978

next question, if mine need replacing, I note the TEC ones at £70 per side, are the aftermarket ones any good?

https://www.davidsilverspares.co.uk/CB550K-1976-USA/part_83533/

[McCabe-Thiele (Ted)]

On my 500 the distance between the coil bolt centres is 100mm, some  aftermarket ones are 90 mm so a bit of bracket adjustment will be needed.

[deltarider]

even cheaper here:

https://www.squaremotorcycleparts.co.uk/products/ignition-coil-x2-honda-cb550-cb-550-1974-1978

next question, if mine need replacing, I note the TEC ones at £70 per side, are the aftermarket ones any good?

https://www.davidsilverspares.co.uk/CB550K-1976-USA/part_83533/

No doubt a generic product. Note that the primary resistance is not advertised. Advertiser should be clear on this! You don't want to find out after purchasing, the resistance is too low.

[beardylondon]

Good point!

And it seems like I’d need 100mm, not 90mm’

[AshimotoK0]

You can get away with cutting out a much smaller section than that described in Ash's file. It's more tricky as you don't want to sever the secondary fine wire, but can be done. The lead that goes a long way through the potting can be pulled through once it is unsoldered. Use a thin wire soldered (temporarily) to the new wire to pull back through.

Be really careful though ! ..if you heat up the brass terminal too much during de-soldering/ soldering ...VERY easy to do because the solder is so old.. then the plastic will soften and  you will break the mega fine secondary wire and the coil is then well and truly f'ked. ....DAMHIKT....  I have done dozens of coils and on a few,  the HT wire has 'snaked' .. so very difficult to push the wire down the hole if you merely pull out the old cable. Plus you really need to clean that hole out to get a good bond with epoxy ... there was never a decent bond between the HT cable and the plastic body .. The bodies on Honda four coils and later twins were never 'potted' ...the body is injection moulded with thermoplastic. Just done some very early 1960's CZ100 monkey bike and CR110 coils and they were potted using what smells like car body filler (polyester resin)!