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[neddy]

Just a note, measuring a round bar with a micrometer does not prove it is round.

[Dennis C]

Neddy
It does if you know how to use a micrometer correctly.

[MadMike]

Dennis, No it does not. It will merely alolow you to establish some dimensions at random points about the diameter.

To be round it must have a consistent radius and diameter from a common centre point.

You must mount it between centres and clock it to check that it is round. Mounting a known test bar between the smae centres will allow you to calculate the real diameter if you use a height gauge or some other means of measuring.

[Dennis C]

Hi Mike
For the purpose of measuring a crank pin to fit a floating bush the correct use of a micrometer will do the job adequately, I understand perfectly what you are saying but on a pin of this type it matters not if the pin is slightly eccentric as long as the radius is consistent.

[Alan R]

Hi guys----this is going to sound rich coming from me of all people but we appear to be straying "OFF-THREAD" at the moment. The original question was "To ruff or not to ruff" Well--- Aye, well there's the rub !! TERRY--we appear to be blinded by our high-tech ideas and angst about roundness and size etc. and have missed the obvious ie}--whichever pin you decide to use you are going to have to split the crank-shaft anyway to fit the new floating bush so, for the sake of £27.50 (plus P&P and VAT)and one extra nut to undo---it's really a "No-brainer", don't you think ?? Fit a new pin and do the job properly. What's to ruff-up anyway---- certainly none of the bearing surfaces, though a proper honing must be done to get a proper fit. OK, lecture over---now let's get this chaps bike back on the road and some miles under his belt. Enough of the theoretical jaw ratchet and get those hands dirty, matey !!

[Terry]

How can I thank you all for your great advice the only way is her' And that you would like to know the outcome.
The bike has been off the road for a year now so another week or so won't matter so I've total all the parts cost and its worth me taking some more time and replacing all the bits you chaps have recommended. As much as I have enjoyed taking this job on I don't want to have to repeat it so the Bullet has been bit and parts will be ordered on pay day.
PS I will clean every nook and cranny with engine cleaner and air and check for flow on each one thank you all again
Terry