Run Ivy Run: So, so wrong...

Since last session I'd been researching thread repair options (mostly Time Sert vs Heli-Coil), getting opinions from the Yahoo group, and generally getting mentally geared up to attempt the operation on the cylinder head.

One thing I learned was the "double-nut" technique for installing/removing stud bolts.  I used it to remove the stud from the model engine (came out easily).  I figured I'd just test it in the cylinder just for kicks.

But when I actually did the double-nut to install it, I was shocked to find it threaded just fine!  So perhaps there was something wrong with the bolt itself this whole time, and not the threaded cylinder hole. 

While I did order a pair of new studs, I didn't replace the one on the other side (yet).  Figured I'd leave well enough alone for now.


After charging the battery, I was getting zero-zip-zilch from the kick start.  It really sounded dead.  I checked spark and was fat and blue.  Then I popped the drain screw on the carb and discovered it was bone dry. 

Ok, so that means the problem is that the fuel line inside the carb is clogged, right?  RIGHT? 

So I pull the carb: detach the throttle cable, pull the fuel line, detach the air filter and the duct tape holding it together.

After doing all of that, I notice that the fuel line between the filter and the carb is also dry.  Well that's odd...  I open up the aux petcock - and nothing flows.  Is it clogged??  NO!!!!

The fuel line was looped up and over the handlebars - the entire issue was a simple case of GRAVITY!!

Frustrating mistake.  Reconnected everything, straightened out the line to let the fuel flow.  And she starts right up.

Trying to redeem the session, I tried installing the brake light switch, but to do it properly you really need to remove the exhaust, and I was too drained (no pun) to do that, so it's for another day.

Run Ivy Run: Easy Come, Easy Go

Just like torquing the head bolts, a seemingly menial task turned into a catastrophic event.

The simple task was to tighten down the exhaust flange bolts after having realized that Roxy's were full tight.  I thought the excess noise and smoke from the head was coming from it being too loose.

While cranking down the upper bolt, I suddenly realized that it wasn't actually tightening at all.  I pulled out the bolt and saw metal shavings.  So... the threads are completely gone.  I tightened up the lower bolt as much as I dared.

I hooked up the battery and tried to start it anyway.  Nothing - totally dead.  Sat and thought on it for a few minutes, and just when I was about to pack it in, I decided to try it WITH the choke.  And she started right up!

She wouldn't hold idle, but starting was no problem. 

So is this related to the exhaust being loose?  It was the only thing that changed, and yet why would she start and run with throttle, but not hold idle.

The fact that it took choke to start her this time means she's running much leaner than before.  Could that point to the exhaust?


Started doing research on thread repair.  Looks like there's the more common Helicoil option for only $20 or so, or there's the higher-end Time Sert kit for about $70, though it's said to be much better long-term.

Both options involve having to carefully drill into the head, though. 

But like Pirsig said in Zen and the Art of Motorcycle Maintenance, the entire value of the bike is now hanging on this one stripped bolt hole.

Decisions, decisions...


Also, found a mix of oil and gas in the pan since the last run.  Clearly the carb had overflowed and drained to the pan - and I realized I'd also left the petcock switched on on the aux gas canister.

But when I loaded up the gas again, nothing leaked.  So I set up the overflow line into a separate plastic container and left gas in the canister to see if something leaks over the next couple days.

Run Ivy Run: Second Running

Tried starting again after 48 hours.  She started right up (again with no choke and a cold day) and held idle using the same screw settings I'd left her with.

Found a lot of oil leaking from the head, though not really surprised.

Got a fully chromed airbox from eBay which I don't think is stock, but still will add some nice bling eventually.

Run Ivy Run: She's Alive!!!

Got the barn find S90 on June 17, 2011.  It's been 2050 days since then!!

And the bottom end and exhaust run for the very first time in maybe 20 years or more!

Hit the garage early with just a few minor odd jobs to finish:

• Set the battery to charge
• Set the air and throttle screw to starting positions
• Added a fuel line for the carb overflow
• Setup the oil pan and cardboard mats
• Added oil
• Duct taped the carb to the air filter

Everything went smoothly until it came time to hook up the battery.  I realized that I'd only ever hooked the battery up to the bike directly; I'd never done it using the switch.  Went round in circles a bit until I realized that I just had to do it exactly as I'd always done it on Astrid (and as the wires were labeled).

• connect battery negative directly to the frame
• connect the switch negative directly to the frame
• connect the switch positive directly to the battery positive
• connect the coil to the "red/blue" switch wire

Then... first couple kicks, nothing.  As expected.  But third kick - she coughs!  Wow.  Had to pause even for that.

But then subsequent kicks, nothing, nothing, nothing.  Totally dry.

On a whim, opened the choke back up.  Contact!!  She fires up.

So she must be running very rich, then.  It was cold, too - 50 degrees or so, and she still didn't like the choke.

After that, I spent the next hour playing with air and throttle screw settings as she was having trouble holding idle.  By the end she was holding a "gritty" idle with these screw settings:

• air = 2 1/4 
• throttle = 3 1/2

There was a point where she just wouldn't hold idle anymore no matter what I did with the screws.  The battery was down to 6.0 volts.  So I recharged it back to 6.3 and then she was able to run again.

She started easily with just a bit of throttle open, but that's exactly as expected given it's Astrid's old head.  If the issues are all carb related, I wonder if I should give the aftermarket carb another try now that I have the angled K&N filter which should be able to clear the frame.  That carb still puts the fuel line on the wrong side, though.

Also, did get a few oil leaks from the top end, though I guess that's also expected from when it ran on Astrid.  But nothing from the bottom end, which is good news.


Oil Notes:

• started adding 150mL at a time
• at 450mL, the dipstick was reading full (this was on a cold engine before it ever ran)
• after running, dipstick showed empty
• added another 150mL to bring it up to 600mL total
• will need to recheck frequently and also do an oil change soon

Run Ivy Run: The Sound of Catastrophic failure

Session actually started off very well.  I installed the stock air filter along with the S90B carb.  Everything went together very nicely.  This is the newish airbox, plus one good cover from the Viola original, plus a new repro air filter for 4-into-1.  Also confirmed the needle is in the middle position.

Before starting the next job of replacing the rear sprocket, I figured I'd torque the head bolts - a little job that just needed doing.

I use a 14mm socket on the torque wrench since they are 8mm bolts and start cranking away.  I'm then surprised to find that the socket starts slipping on the bolts when they get tight.  This strikes me as odd, but I don't actually PAUSE to ASSESS the SITUATION.

If I had, I would have seen that the bolts are in fact 13mm and not 14 like they usually are.  I was stripping them.

As I was tightening down the top left side bolt, there was a sudden CRACK and the wrench came off suddenly.  Apparently, I'd torqued the bolt enough that it ripped the bottom end rod in half.  Well, that's just great...

Though, if that rod was going to fail on torque, then it was always going to fail.  There's no way I could have under-torqued the bolts, somehow expecting the rod was weak.

Though I'm still not sure if the slipping socket had anything to do with it.  Did the slippage cause the wrench not to read the torque correctly which meant I was over-tightening?  I don't think so... but...

So definitely a major issue.  I think it's going to be a nightmare trying to remove the broken rod and replace it.  But I figure the engine should run with only 3 of 4 connecting rods???  Well, at least it that can't affect start up, can it?


After the shock of that wore off, I did the rear sprocket.  Pleased to find that in general, all the steps came back easily.  The job actually took a lot less time than I'd thought it would.

3d Printing: Transmission display

The tranny "cozy" was fun.  A lot of measurements and I'm honestly surprised it came out so well with minimal versions.  The frame locks together with 6mm bolts and then sits in the mount at a 45 degree angle for desktop display.

Also good for maintenance/education since the gears will turn and engage within the frame.

Run Ivy Run: Aftermarket woes

Freed the left throttle grip just because.  Took a lot of WD40 and elbow grease.

Found all 3 air boxes while also doing a big garage storage re-org.  Since the K&N didn''t fit the aftermarket carb, was hoping to get the stock box installed and just wait for the rubber hose to show up.

But the aftermarket carb can't fit the stock air box either!  Since the gas line sticks out the back, it totally interferes with the fit of the box.

New strategy:

First, setup one of the stock carbs plus the stock air box.  At least this maybe eliminates some unknowns by sticking with stock.

If that fails, or even in parallel, get the K&N RU-0100 offset version which should theoretically fit the aftermarket.


Carb and filter audit:

1. "$10" - has no covers but otherwise seems in good nick
2. Viola original - right cover is stuck on and there's an old filter bolted inside, so effectively useless until the cover is freed
3. "Number 3" - this came with 1 plastic cover, but the tab has broken off.  Otherwise in very good shape, so I stole 1 cover from the Viola box to make it complete.

Also, as of today, we have 3 used filters and a brand new repop one from 4-into-1.

Run Ivy Run: 2017 Kickoff

First garage of the New Year and with the rearranged garage parking.  Had to drag myself down but feel like the mojo is coming back.

1. Tightened up the headlight bucket so it wasn't wobbly anymore.  (Why did it take me so long to do that?)
2. Added the right clutch/CC gasket (last one in the binder)
3. Added the intake-to-head gasket (also last one in the binder)
4. Setup the fuel lines.  Used 3/16" which fit the carb, the shorty filter, and the aux gas line.

All was going well, UNTIL...

The last thing was to add the K&N to the carb and only today did I discover that it's too big!!  You could probably forcibly squeeze into into place, but it's a very, very tight fit.

Possible options:

• Just force it into place
• Find a different K&N filter (either offset or shorter)
• Use the stock filter
• Use the stock carb
• Cut down the K&N filter 
• Remove the heat gasket temporarily (good for the test start)

3D New Year!

3D printed a temporary carb mount!  Possibilities are endless...