Red: Roxy Carb Saves the Day

First checked the throttle cap and saw that the ferrule had come off the housing.  Could that have been causing the issue by letting in extra air somehow?

After fixing and tightening that up, started the engine and it would not hold idle at all, no matter how dialed in the air screw was.  So the throttle cap was indeed affecting it somehow.

Then did what I had planned to do anyway, which was to swap that Sheng Way out entirely for the carb just pulled off Roxy (CS90C).  It would have the extra benefit of keeping the vintage Keihin in good running order.

Swapped it out (which meant it joined its original intake, also pulled from Roxy).  Started her up, and she ran like a champ.

Upstairs, pulled the Sheng apart to find that familiar white residue on the idle jet.  And even after two rounds in the ultrasonic, it looked like the big hole was jammed up (couldn't see daylight through it at all).

So knowing all this, it must have happened this way:

1. When I swapped Sheng #1 for Sheng #2, I must have disturbed the ferrule and created that air leak.  That would explain the racing idle that was not fixed even when I swapped back to Sheng #1 as a test.  It also explains why adding the intake gaskets didn't help.
2. The clogged slow jet in Sheng #1 also explains why it always needed so much air screw to run at all.
3. When I fixed the ferrule today, it stopped the air leak, but the air leak was the only thing actually allowing the carb to run at idle at all.  With the air leak gone, the clogged slow jet came into effect.

Also swapped out old taillight bulbs with LED on both Roxy and Ivy.  (Ruiandsion 1157 LED, $11 Amazon)

Ivy II: Seat Reshaping

Just used the bread knife to reshape the foam to match the contours we did on Red.

Red: Idle Issues Continued

Thought that if an air leak was the issue, then I'd swap out the intake for the one I just pulled off of Roxy.

Did that and idle seemed better, though still rough.

Moved the needle back to the middle position.

Roxy: Bore Size Reveal

So turns out Roxy's cylinder is a standard 50mm. 

So why then did she always feel like she had a little more grunt?  She seemed both heavier and torquier than Ivy.  Or has it just been my imagination this whole time?

And why the breather tube on the tappet cover (as if it needed to bleed off loads of extra pressure)?

Roxy: First Tear Down Ever

Hard to believe that after having owned Roxy for this long, still had never pulled the top end apart down to the cylinder.  Was to be the big day when we finally discovered if she had a big bore or not.  Would answer the question of why she seemed to have so much grunt or why she had the relief valve on the tappet.

She was a bit tough to get apart.  Had to knock a few covers with the screwdriver handle to jog them loose.

Toughest was the head cover.  Wouldn't budge.  And for some reason, with it still on, I couldn't get the head completely off the cylinder studs.

Ended up separating it using a Philips as a wedge (as gently as possible).  But once that was off, the head came off.  Pulled the cylinder but left the piston.

Cylinder bore actually looked great.  Still had the cross hatching.  Just a narrow rim of discoloration (corrosion?) on the outside edge.  Thought for sure it would be in much worse shape.  But if that's the case, then why the smoke?

Started this tear down as the first step to cleaning her up and putting her into Preservation Mode.

Red: Epic Bad to Worse

Started with the easy job of swapping out the Left Cover (again).  This time for a new and very clean eBay one.  Went back to the cork-rubber gasket.

Then decided to swap out the Sheng Way carb #1 for the recently cleaned #2.  Swapped it over, went to start and no joy.  Engine would race and then die.  Could not hold steady idle. 

Felt like an air leak.  So decided to add the missing gasket from intake to carb that had been missing this whole time.  Stock gasket was a bad fit for some reason, so ended up cutting a new one from the Fel-Pro pack.  After cutting one, decided to cut a second and put it on both sides of the insulator.

Tried it again and no joy.

Removed the intake from the head to check the gasket there - and there wasn't one!  Could have sworn it had one all this time.  Thought that was bound to be the solve, but after adding a stock gasket, it was the same issue.

So moved the needle down to second from bottom but still very rough idle.

Red: Epic, Forks and Leaks

Had put off these bigger jobs for a long time...

Started by draining the oil to take another look at the left cover oil leak.

Saw that there was definitely old gasket on the cover, so scraped some off and then also used 2000 grit and with cover flat on plexiglass tried to smooth it down evenly.

Went back to the regular paper gasket to get a "default" setting.  The cork-rubber gasket seemed to be holding up fine, though.

After that, swapped out the clutch.  Screen filter was VERY dirty.  Pretty much blocked solid.  Some sludge in the clutch basket trap (clutch got swapped anyway).

All that took three hours.

Then on to the forks.  Pulled just the right one and removed both of the ACE o-rings.  With wheel back on, the fork was spurting oil on every compression.

Put the ACE o-rings back but put some grease around them to try to prevent the forks from sticking.

EDIT (next day test ride results):  Unfortunately, still getting a small leak from under the left cover, but now a BIG leak coming out the top.  Did sanding the bottom introduce a warp at the top?!

Right fork still leaking but they don't stick anymore!

Clutch much better now.  No more "heavy" third kick.  Seems to start much easier, too.  Also ended up dialing the throttle screw way down.