If you've gone top to bottom, inside out on the carbs, with 100% certainty, and it's still not running right, YES, you PROBABLY need new carbs.At what stage are slides/carb bodies just too loose or flogged out to attempt to deal with? Bite the bullet, replace em and be done with it?
or have another go with the originals but now on fresh cables. and if still too fiddly then fork the $600+ ?
am I over thinking the engine idling too long before being run-in, while tuning after a fresh rebuild?
Can of worms, for various reasons ...rebuilding rocker boxes.
There should be only four copper washers total, one each side of each feed banjo.washers
Seems to be a lot of copper ones
In theory, there is a sketch in the '71/'72 workshop manual; in practice it's wrong ... (shows the pre-'68 assembly order).Need to work out what order all these washers went in.
Thanks Stuart! Yes so it seems.Can of worms, for various reasons ...
Depends. Your photo. shows you're testing a pattern switch, not an original Smiths. If that pattern switch is NPS thread, it's sold as a replacement for the '74-on switch, which Smiths supposedly rated for 3 psi ...oil gauge
teeing to run a pressure switch.
switches are set for 7-11psi.
gauge wasn’t very detailed at lower pressures, but I reckon it barely pushed 7 before switching. Likely around 5,
It would be a bad idea, unless you want to be freaked after every spirited run in hot weather ... then the pressure can fall well below 20 psi, although still be perfectly-adequate.at revs it’s can be in the 50-80lbs, and in the 20-25 at idle. Given this would it be that bad an idea to fit a generic switch more suited, say one preset for 20psi… ?
Was reading up on those efforts of folks having rocker shafts grooved for an oil way either with dremels and jigs or via the expense of a machine shop (i'm not thrilled on either), and noticed this point made;I don’t think I’ll opt to cut grooves in shafts. I think I’ll read, and re-read, and just opt to go with the most ideal washer setup with the standard solid (un-cut) rocker arms and shafts (which I think is very much as per your suggestion above ie losing the 3/8 washer).
As per the above, does anyone know if there is any advantage to rearranging washers without grooving shaft? If no clear benefit I may have to go ahead and assemble as per factory manual...?I’ve reassembled the rocker boxes in the same way as they came off the bike i.e. the “incorrect” workshop manual method. Reasons are that my attempt to mod the old shafts wasn’t successful and I received a negative response form a well respected old bike mechanic based in Wales. Without the additional oil-way re-arranging the thackery & thrust washers is of little benefit and in fact gave me a new problem of the shaft sliding too far into the rocker box….so I’ve left as is and will live with the consequences if there are any.
anyone know if there is any advantage to rearranging washers without grooving shaft? If no clear benefit I may have to go ahead and assemble as per factory manual...?
Ummm ... if there wasn't an advantage/benefit, why would Meriden have changed the washers order in the '72 parts book (admittedly still a half-arsed change), and then machined the oil scroll on the rocker shafts from '73? Parts books were reissued every year, workshop manuals were only updated, at best. Afaict, reassembling '72 rockers "as per factory manual" (workshop manual?) is probably the worst you can do?You should follow the order shown in the '72 parts book
With respect, you have not noticed, or ignored, more important things in the same thread:-rocker shafts grooved for an oil way either with dremels and jigs or via the expense of a machine shop (i'm not thrilled on either), and noticed this point made;
When the bikes were new, any factory's primary criterion was cost - the cheaper they could build it, the more profit made when it was sold. Coupled with that was the tiny warranty period before any problems became the bike owner's. We aren't governed by those criteria; why wouldn't we do it better, especially when the fix isn't complicated?The groove dimensions are not critical and can be done with a Dremel. An alternative is to grind a shallow flat on the shaft. Whether using a groove or a flat on the shaft, they should be positioned at the top in the unloaded area between the rocker and the shaft. I made a pop mark at the outer end of my shaft to able to confirm the correct position of the shaft when assembling and tightening things up.