Topic: Rebuilding 1977 cb550F Engine - tachodrive

[Rolfbulmer]

Hey guys,

I'm UK based and just purchased a 1977 cb550F! I'm currently rebuilding the engine and the schematics say there should be a thrust washer on the tachodrive spindle, I have three questions:

1. Does anyone know where I can get a thrust washer for the tachodrive please (preferably from the UK)?
2. Can an alternative washer be used
3. Do you actually need to have a thrust washer or washer at all?

Many thanks.

[Rolfbulmer]

Thanks calj737 for the reply,

I have seen the same schematic as in your link.
The questions i have are:

1. Does anyone know where I can get a thrust washer for the tachodrive please (preferably from the UK)?
2. Can an alternative washer be used
3. Do you actually need to have a thrust washer or washer at all?

[flatlander]

1 - try david silver spares.
2 - the washer is very thin. i had it in my hands but didn't measure it. in principle you could use a different one if (!) it has the same hardness and is of such hight that the drive meshes well with gears on the camshaft, play on the other end is not too much and not too little. much easier and cheaper to get the original part.
3 - you need it, otherwise it's hard steel agains softer material which will wear through.

[Rolfbulmer]

Hi Flatlander,
Thanks for your help.
I have tried David Silver and the part is discontinued and no longer available.  I have tried 1 other supplier with the same outcome.
I guess i just need to continue looking and hope one will eventually turn up - very frustrating that such a small and critical component can be so difficult to source.

[Stev-o]

Try posting a tread in the parts wanted section of this forum.   Or on the UK based forum, I'm sure someone out there has one.

That failing, you may have to fabricate one...

[flatlander]

if you're not in too much of a rush, one will turn up sooner or later if you post a wanted ad. guys who convert to an electronic tach will have a spare one of these.

[bryanj]

They are out there but rare, you may end up with a complete cam cover to get one. Try putting the part number into ebay they do occasionaly turn up just on number when sombody buys out a shops old stock.
In UK try DK in the midlands or there is a breaker in Stratfod on Avon plus seen a breaker in cornwall splitting a complete bike. The alloy casting will cost you over £100 on its own

[Rolfbulmer]

Thank you guys for all your great ideas. I will try all of them and see how it goes.

[Little_Phil]

The i/d is oversize, but can it be ground down without harming properties?

https://simplybearings.co.uk/shop/p360203/Major-Brand-CP715-Thin-Needle-Thrust-Washer-7x14.4x0.8mm/product_info.html

Correction: meant o/d

[Nurse Julie]

If you joint the UK Forum, which you may have done already, ask the question on there.
I may even have one but I'm away at present, so him indoors, Trigger on the UK Forum, can have a look to see if we have any in stock.

[Tim2005]

Just buy some shim washers, plenty on ebay etc such as this, it may just take a little trial and error to find the correct OD

https://www.ebay.co.uk/itm/224396366976

[Rolfbulmer]

Thank you for the recent replies and ideas.
I’ll post what I eventually source.

[Rolfbulmer]

I have got the washer I need through ebay UK from bikerdc1.

[bryanj]

Well done, the bits are there just hidden