Red: Pistons & Rings

Continuing carpet work from yesterday, wanted to take a look at the pistons I had.

More revelations...

So Piston #1 is Honda and is measuring in at 50.2 mm.  The top and second rings were good.  The oil ring didn't pass the gap test, which I now realize is because I stole it from a piston of a different size.  Which is all now moot since I snapped it!

Piston #2 is an ART piston measuring at 49.94 mm.  

And the Honda piston at 50.2 fits perfectly in the Orange jug.

The ART piston fits perfectly into the Mystery jug.  

Go figure.

I believe the S90 standard size was 50 mm (based on some Yahoo posts), which means both the Honda piston and the Orange jug are 1 oversize (+0.25).

The ART piston and the Mystery jug must be standard.

Family Portraits

Unusual to have all 3 bikes out, so took the opportunity to snap some family photos.

Red: Engine Investigation

Had the day off and decided to audit all the jugs and cylinder heads, starting by pulling the "Mystery" one from Astrid.  Simply can't remember its origin.  I know that I swapped whatever was on Viola/Ivy for the Astrid top end back when we were getting her running, but was that the original Viola top?  I have another cylinder head marked "Viola", but maybe that came as a spare part?

Regardless, I pulled that jug and head from Astrid and brought that up for carpet work along with the "Viola" one.

Stated by inspecting the valves, which I did on the Viola one (everything was within wear limit), but found the Mystery rocker cover screws were frozen and stripped.  Again, not sure why that never got addressed.

Tried to mate the Viola head on the Mystery jug and came to the realization that they are two completely different models.

The Mystery jug has a 68mm surface with no groove in it.  While the Viola has a 65mm cylinder surface.

Are these really 2 different S90 jugs?  I need to lookup the Yahoo discussions again.  I think the Viola 65mm is definitely stock S90 so if anything is different, it's the Mystery one.

Red: Mount New Shock

Mounted the newly painted shock in prep for the ride down to CHP.  Dropped it while trying to remove the painters tape - luckily I only scratched up the hidden side!

Red: VIN Verification

Got VIN from Officer Wong - he actually did all the paperwork without even looking at the bike!

So just a tow down to the station and back with Dave and his truck.

Ivy: Tank Vacuum, or Obvious in Retrospect

Went down for another session to revisit the engine issue.  When I twisted the gas cap off, I heard the distinct hissing sound of air rushing in.

So it was a vacuum issue in the tank.  Now all the symptoms added up - the engine dying after a short period, but then running after resting a bit.

I had removed the extra DIY gaskets from the cap because they looked ragged.  Could some debris have found their way into the vent hole.  Where is the vent hole anyway?

I tried loosening the cap a bit and went for another ride around the block, but same thing happened.

Finally, just switched the cap with Roxy's to test - and she ran perfectly.  So it's definitely the cap.  Just need to figure out where that vent is and then clear it.


Also checked the odo against a phone app and found it was dead on!!  Seemed accurate down to 0.01 mile.

Red: Brake Pedal Spring, New Shock

Odd jobs for Red.

Added the new brake pedal spring.

Unboxed and painted the new shock (which replaces the crooked one).

Also tested the new aftermarket dual petcock on the dented tank.  Found that the screw seemed too long and wasn't pulling it flush against the tank.