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[ChrisD]

Hi DanielBen.

To add to Alan R’s comment above valve seat recession (and because that website image won't open for me), please find attached a picture of the recession of my exhaust valve seat – 1996 500cc OEM running unleaded petrol of 95 octane in Cape Town. You can see how the seat has eroded away from the valve by reference to the edge of the seat and the plug hole. This happened between the two inspections that were 1000kms apart. You can scale off the amount of recession, some 3mm around the whole valve seat. The sets were changed to our hosts hardened seats and no further seat problems. Cheers, ChrisD

[Mark M]

Well there you go, it does sound like it's called the 'idle screw' by Micarb. (I would prefer throttle stop screw as that's what it actually does, 'idle screw' implies it actually adjusts the idle which it can only do if everything else is set up properly. Anyway, Victor Meldrew back in the box.) In order for this screw to work the throttle cable itself must be adjusted so there is no free play (slack). This means that when you turn the throttle rotor you can see the slide lift straight away. Before you do this, turn the 'idle adjuster screw' right out so it cannot interfere with the slide dropping right to the bottom of it's travel. Once cable is adjusted correctly then the 'idle screw' can be turned as I described so it just lifts the slide.

REgards, Mark

[Alan R]

Hi guys !!---------- Daniel, first of all here is a video showing how you how pushrods should look when adjusted correctly............A very small amount of up-and-down play is preferable to a slightly tight one as this indicates both rods are positively clear of the rocker arm / valve cap........................................

From your very latest reply ( Adjusting numbers 15 and 17 in the lower diagramme ) you say that adjusting No. 17 had no effect at all ??......Then there's your answer I'd say}----the idling fuel circuit / jet is blocked......To give initial adjustment on No. 15 ( The throttle stop screw )}------remove carb and loosen the throttle cable a lot!!......Drain off remaining fuel via the big drain nut at the bottom of the float bowl and leave it off for the moment......Unscrew No. 15 untill the retaining screw goes slack....Now hold carb up to light and look into the mouth and all you will see is blackness................Steadily screw in No.15 until you begin to see some light at the bottom of the inlet tube...It will look like it's the Cheshire cat's grin.....Something like this}------------------------------------------------

[DanielBen]

First i'd like to thank you all for giving me all of this wonderful advice.

I promise to keep updating.

Thanks!

Daniel