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A couple of "tune up" questions...

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Bryanj:
Most confusing thing in my currebt trade of HGV is up to 32 ton is english ton over 32 is metric tonne and 1,000 kg is not a ton

Johnny4428:
This is certainly a drawn out affair. The transition from imperial to metric. My very first job on leaving school at 16 was working in a timber yard. After a shipment of timber to the islands the bings were all mixed lengths so first job was to sort all the timber into the correct lengths - 3.0, 3.3, 3.6m etc going up to 6.0m. It was great I very quickly learned my metric. Of course we always still referred to a 6 x 2” or 8 x 2” or whatever. So customer would come in and it would be marked as 2 x 4.8m x 6 x 2” rpos.

Matt_Harrington:
About 20 years ago (?) they tried to force the TV & Monitor market to move metric. It failed miserably and screen diagonals still are measured in imperial.....

K2-K6:

--- Quote from: Mikep328 on September 08, 2023, 11:40:44 AM ---I disassembled the carbs/cleaned all parts thoroughly.   I reassembled with original brass, set the float levels,  and installed new (NJ) Orings and bench-synced the carbs.  On the bike with engine running each mixture screw functions properly, changing the idle as it is screwed in/out so I don't believe there is any issue with clogged passages, etc.  I'll richen the mixture slightly, as suggested.

I'll check the tappet clearance/adjust if needed - it was allegedly set properly by the shop tech prior to my purchase... ;)

--- End quote ---

Something that may help in details. Often the great wide opinion out in internet-land is that the idle airscrew simply changes absolute mixture, when in reality these design change the "slope" of mixture leading up from lowest rpm to link into main jet response territory, which can be much further up in influence than many appreciate.

Thinking of a simple way to express it, thoughts like the following to expand a visual representation of them:- if you had a ladder to reach a second floor window of your house, you'd likely extend it to comfortably reach the sill, while leaving it at a decent angle for you to climb. Too steep and you risk it falling outward  :o too shallow and you risk it sliding down the wall in the opposite to before.

The airscrew adjusts both reach and slope to get the ladder to let you comfortably reach the window safely. If the ladder is too long to get into range, that would be the pilot jet too big and not let you get down below the guttering, too short and no chance of reaching the window the pilot jet being too small.

With all passages clean and correct brassware,  then it should allow you to trim that mixture slope until it attaches meeting all the requirements in blending  into the mainjet lower reaches and not give any discernible flat responses, rich or lean. It doesn't matter exactly where the screws end up (within reasonable amount of turns out range) but it will calibrate your carb, your airflow, your airfilter, at your altitude to bespoke tune the idle circuits as  Honda and Keihin designed it.

If you live in a bungalow, you're going to be mystified by this  ;D

Mikep328:
Went out today and checked the tappet clearance - they were .003"+ so I reset them all to .002"  Then I synced the carbs with a gauge set after first calibrating the set so that all gauges read the same when attached to the same cylinder.  I had bench-synced the carbs a few weeks ago and was pleased to see that they all cylinders were within a needle's width of each other.  I tweaked them so they read exactly the same though I doubt that a needle-width difference matters.

I richened the mixture by 1/8 turn on each carb but it was raining so didn't take the bike out to evaluate the change.  In the parking garage it accepted a quick throttle movement from idle with less hesitation than previously.

One thing that I was NOT happy about -  when I started the bike from cold there was visible smoke from the exhaust though it seemed to disappear after it warmed up.  Couldn't really tell the color but it smelled oily to me.  However, the spark plugs all look good color-wise with no sign of oil or fuel fouling.  My wife was behind me on her bike riding to Bristol the other day and she didn't mention seeing any smoke from mine.  I hadn't asked her to look for it but I'm sure she would have said something about it had she seen any smoke.  In any case, further evaluation is in order.

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