Venting

Man, have I got some stuff I really need to get off my chest.

I know you know what I mean.

It starts with the small stuff that gets under your skin — worn shoelaces on your boots, bits of software that don’t work and have never worked, the endless number of people who you don’t know who are happy to call you to ask for your money on the phone.

And if it was only the small stuff, that would almost be OK.

But it’s not the small stuff, it’s the big stuff, and its got everyone that I know in a constant state of fully clenched and ready to blow.

I mean, look around you.

I’ve never known a time when there was so much on the line, with so little sensation of which way it was going to go.

But that’s really not what I really meant to talk about, it just has a way of creeping in.

***

“Dad, I got a problem with the bike.”

“Oh? What kind of problem?”

“It doesn’t run.”

“That seems kind of non-specific. How doesn’t it run?”

“Well, it had been backfiring, and it seem like it’s always going to stall.”

“Does it get better or worse when the bike warms up”

“Neither. It sucks all the time. It got so bad last time I didn’t think I was going to make it out of the parking lot. I parked it.”

“Ok. I guess we’ll have to get it back to the shop and see what’s what with it.

Do you think its ridable enough to make it home?”

Keep in mind that the ride home bisects the most trafficked roads of the whole greater Baltimore-Washington metro area. If you have doubts about power delivery it might not be the right mission profile.

“No way.”

“Ok, then we’re going to need a Plan B.”

***

Plan B came in the form of my new good friends at U-Haul.

U-Haul, it seems, makes Serious Bank from Motorcyclists That Like To Trailer Motorcycles.

And while I have always been of a bent to avoid joining that club, I think there is some sort to ‘get-out-of-jail-free’ card when the motorcycle in question cannot move under its own power.

At least, that’s my rationalization and I’m sticking to it.

Anyhoo, the nice folks at U-Haul mave designed a rental trailer whose only job is to move motorcycles. It’s a 5′ x 9′ all-aluminum utility trailer, with a built-in loading ramp an a neat front wheel chock that is part of the trailer’s structure.

About 5 minutes on the laptop reserved one — in real-time, on a Sunday afternoon — located in Gaithersburg about halfway between Jefferson and College Park.

If you’re in a Jam with a motorcycle that won’t motor, its hard to imagine a more convenient way out, at least if you own something with a trailer hitch.

***

While I waited for U-Haul to call me back to confirm, I called Harley-Davidson of Frederick. HD of F — it should be observed — is the only motorcycle dealership that I know of that is cheerfully open seven days a week. This feature has already saved a few Sundays and Mondays for me and the Blast already.

I had a list of parts that followed my lines of thinking given very minimal available troubleshooting information. One or two, or maybe three things was going on here. We were either running crazy rich or crazy lean.

The statistically least likely thing, and hence not worth buying parts for, was that the Blast’s teeny weeny electronic ignition box had tossed it.

The crazy rich option would involve the predicted death of the electro-mechanical auto choke unit, and I already had parts for that.

If you were willing to move past that then we were wither dealing with a completely clogged carburetor — which also seemed unlikely, given that the bike had been running reasonably well immediately before it’s untimely mid-stroke demise, or with a fuel system that wouldn’t flow any fuel — which was either a clogged petcock…

or Venting.

Now I have been driven beyond the bounds of distraction by fuel systems that wouldn’t flow fuel.

The Blast, fortunately, is a bit more modern motorcycle, with better coverage from its Internet user forums. User forums which thoroughly document the frequent failure of the tank’s venting system, whose key component is an EPA-mandated rollover valve that has been known to cut off flow when the system was demonstrably straight up and down and in no way rolled over.

So I ordered a complete set of carburetor jets — slow speed, main and needle — a tank petcock, some vent line and a rollover valve. A rollover valve, it should be noted, that has had its part number superseded by a redesigned part at least five times, according to Shell, the HD of F counterperson.

You may or may not find that noteworthy, but I did, anyway.

HD had three of the six parts in stock — the others would be available in a day or two.

5 minutes after I got off the phone with HD of F, U-Haul called me to confirm that the trailer was available, so Finn and I grabbed our jackets and headed for the pickup.

***

Fast forward to a parking lot outside College Park.

Finn tossed me his keys. I threw a leg over the Buell, turned on the fuel, and hit the starter. The bike fired on the third stroke, and came right up to its high idle.

It was enough to give one a false sense of security.

I blipped the throttle a few times. The first two times, we got response, and revs. The third time we got boggage. When I let the throttle go, it stalled in deterministic and terminal sounding way. I waited a few seconds and tried the starter again. The bike fired, stumbled and quit.

“You were right. Never would have gotten out of the parking lot. Let’s load her up.”

***

Back at the shop, The Blast took up a spot on its swingarm stand, with my LT temporarily exiled outside to the driveway.

The next afternoon, when the opportunity presented itself, I test fired the bike on the stand. The previous pattern repeated, except when the bike first started to stumble, I reached forward to the fuel cap latch, flipped it open and pulled. The cap didn’t want to come out — there was vacuum in the tank. A bit of a more determined tug liberated the cap, and three quarters of a second later, the engine returned to full song.

Venting it was. Gasoline engines don’t run well when they can’t get any, apparently.

***

A day later HD called to let me know they had received most of my order, but were short three of the carb internals — those would be coming in in a couple of days.

I swung by on the LT at lunchtime, and resolved to find the hour or so it would take to drain and refit the Blast’s fuel tank.

On my way back inside I yanked the Blast’s wierd-alice conical air filter — a reusable dry gauze type. I grabbed a small tin container, and set the filter in dishsoap to soak inside in the worksink.

***

When the weekend rolled round, it was time to make this bike run.

The Buell’s fuel tank is on the less complex end of the modern “how-hard-can-we-make-it-to-remove-this-motorcycle-fuel-tank” spectrum.

I know this, because my K-bike is all the way on the other, wrong end.

A single 10mm bolt and the oil dipstick retain the tank’s plastic cover.

Two more 10mm bolts under that cover and some cylindrical rubber bumpers get you down to the single screw on the fuel line and your tank sitting happy on the workbench.

Somewhere along the line, I inherited a little Black and Decker Workmate folding workbench and lightweight vise. It’s an ingenious little thing, with the two halves of the worksurface driven and located by two hand operated jackscrews.

For a job like this, its perfect.

I opened the surface of the Workmate all the way up, and sat the tank on it so that the petcock sat between the halves of the table.

I grabbed the gas can for my lawnmower, pulled the filler neck off it, and sat a funnel in its place. I opened the tank’s petcock to ‘Reserve’ and then just let time do its magic.

While it was draining, I removed the old tank vent line from the frame, in preparation for its replacement. Predictably, an attempt to blow air through the line produced — in addition to giving me ‘HighTest Breath’ — wholly unsatisfactory results.

One of two things was going on. Either this was another one of those ‘dang bugs’ stories — with a spider having engineered an effective blockage of the line — or it was observable manifestation of the apocryphal stories about modern alcohol-laced fuel turning soft fuel system bits to mush — with the line having melted and welded itself internally.

Either way, the tank hadn’t been able to flow fuel, and with no fuel, well…

My thoughts were that if one bit of rubber had possibly been mushed, then all of them were suspect, so we’d clear out everything so we wouldn’t have to back here for say, another 15 years or so.

Fortunately, I had a really good mental image of how all of the tank components worked, because when one of my son, Apprentice Architect Finn’s professors assigned a cutaway drawing — of anything the student chose — Finn had drawn this.

v__d72f

The shop manual might be good, butĀ for me anyway, this was way better.

I’ll never quite understand why the Blast’s designer’s did this, but they did. The fuel tank’s rollover valve stem is just long enough that — once the vent fitting that retains it is unscrewed — it is too long to be removed from the tank unless the tank’s cap retaining ring is removed first.

Which, if you think about it for a second or two, represents a bit of sleight of hand, both to disassemble and to put back together.

No matter — I managed to remove the top ring and get the old rollover valve out without dumping it into the bottom of the tank. My shop manual indicated that the rubber seal and tank ring needed to be coated with a thin layer of Hylomar aviation sealant.

Two things occurred to me concurrently as I was looking at the disassembled parts in my hand. The first was that I actually had some Hylomar, because as an impressionable youth I had been (unwillingly) instructed by Ted Porter, who had impressed upon me that using anything else for several critical BMW Airhead assemblies constituted some kind of wrench malpractice. The second was that these parts weren’t the original factory parts — someone had replaced this valve before — because the sealant was nowhere in evidence. And that the person that did this clearly didn’t know Ted, because they didn’t have any Hylomar.

After a very thin coating was applied to the rubber seal, I replaced the rollover valve and carefully retightened the eight allen bolts holding the top ring in place. I reinstalled the valve’s top fitting on the outside of the tank, making sure to point the barb to the 11 o clock position so it would be able to accept the rubber vent line.

I then removed the two phillips head screws that held the petcock to the bottom of the tank and removed it. The petcock’s nylon screening looked very discolored when compared with that of the new part. Being easily amused, I giggled a little at the sight of the ‘Made In Italy’ script on the petcock’s valve handle. As someone wrestling with a motorcycle that was inexplicably dealing with niggling reliability issues, this is just the sort of confidence builder one needs, eh?

A new o-ring, and retorquing the two phillips heads yielded a fuel tank whose entire fuel flow path was now completely new.

I took a few minutes to look at my laptop to check the shop manual to see how the fuel vent line was supposed to be routed. The routing was fairly elaborate – following the left side of the oil-in-frame backbone, crossing in front of the carb and then ending inside a frame recess in the frame’s rear section. While probably a good idea in terms of protecting the vent from road debris or water, it did make me wonder about how good an idea it might be to have fuel vapors hanging out in close proximity to the battery and fuze blocks.

Of course, that hadn’t been how the line I had removed had been routed — it had been routed down the front frame downtube so that it exited near the riders left footpeg –a spot that was prone to sucking up water or debris from the roadway. I took a few minutes to thread a new vent hose in the factory position, engaged the OEM frame ties, verified that the hose wasn’t kinked or pinched, and then cut the front to length.

I replaced the tank on the motorcycle, and reattached the fuel line, hold down bolts and the tank retaining bumpers. I replaced the clean and dried gauze air filter, snapped the airbox closed, and replaced the plastic tank cover. I refilled the tank with about a half gallon of fuel from the lawn mower gas can, waiting a few seconds, then checked the new petcock and o-ring for leaks.

Dry as a bone.

I turned the fuel tap to ‘Reserve’, waited ten seconds, and fingered the starter.

After three or so Whoooomps, the big single lit up and came up to a solid high idle.

Starting, though, had never been the problem.

I gave the bike some gentle throttle, verifying that we had response, and working to get some heat into an engine that had been sitting for more than a little while.

After a few minutes the autochoke came off — causing some minor drama as the carb’s internal enrichment port was slooooooowly closed. The Blast’s single took up an even slow idle — smoothly taking blips of the gas — and continued to do just that and nothing else.

Which, considering the relative scarcity of that a few minutes before this, was beginning to look like progress.

After a few minutes of running on the stand and giving her an occasional blaat of throttle and then letting the engine idle, there was no sign of the fuel starvation that would have formerly rendered the Blast dull, lifeless and inert.

It was time to get this little bike off the service stand, out of my garage, and tested on the road.

***

It didn’t take more than ninety seconds to be absolutely sure that something significant had changed with the Blast.

Where it had formerly been a tad fluffy off the bottom, but pretty good when the revs came up, now it was …almost punchy.

Ok, well that might be overblown, but drivability was much improved, and opening the throttle was definitely fun and encouraged you to do that some more.

***

I ran the bike through a few more heat cycles over the next couple of days, and except for the rough moments each time the autochoke finally closed, the little bike was running like a champ.

Now I’d have to look for an opening to get it back to College Park.

***

Saturday came and Finn was using every communications medium available to him to let the Home Office know how much he’d really like to have his motorcycle back.

Call it an opening.

Of course, it would a sunny 35 degree day opening, but an opening is an opening.

Doris hopped in the pickup and headed towards Finn’s place while I layered up for the ride.

This is one of those days where a good fleece top and an Aerostich suit can make 50 plus miles of what could be uncomfortable pretty comfortable.

I also had a new pair of cold weather gloves to break in, so this seemed like an opening for that, too.

***

The Blast started pretty well, especially considering the overnight low had been just under 20 degrees F.

As I rumbled up into Jefferson, I remembered I’d been wondering how far this bike would run before hitting Reserve, now that it would actually flow fuel.

Whereupon, three quarters of a mile from home, and showing about 80 miles on the trip odo, I promptly ran out gas, and turned the petcock to Reserve.

I wouldn’t have to wonder anymore.

After a brief stop at Jefferson’s BP, to purchase $4.51 of premium fuel, I pointed the Blast over Mountville Road, cutting across the southern end of Frederick County to miss Frederick City traffic and use a few miles of backroad dancing to make sure the little bike was running fully on song. Mountville and Maryland 80 are both delightfully technical, with lots of grades and corner combinations to string together. With the Blast’s 500 single up in fourth gear it was eager to carry momentum, turning sharply in to each corner and torquing out in a single cylinder machine gun symphony.

Singles are cool.

Apologies to Dr. Who, and to bowties.

After merging on to Interstate 270, it was clear that the bike had been subtly starving for fuel long before it had failed completely — this had been a problem that had been degrading slowly for a very long time. Before the fix, the Blast hadn’t really made usable power in top gear until about 75 miles per hour — post fix there was good power from about 63. Rolling fourth gear on at lower highway speeds actually produced a reasonable rush of power.

34 horsepower doesn’t sound like a lot, unless you’ve been spending some time riding the same bike around with it making 27 for a while.

I’ll also admit that BMW S and LT fairings make one spoiled when transitioning to the Blast’s tidy flyscreen — its hard to imagine how doubled over I’d have to get to gain any coverage from that. Still, other than two or three numb fingers on each hand, and a couple on each foot, it was a pretty nice day and a pretty nice ride.

Greenbelt came up a bit too fast, really.

Finn seemed glad to see his motor.

We locked the Blast up and headed out in search of a burger.

***

The next day I was reading my Sunday paper, when I heard my phone vibrate.

A text from Finn.

Just took the bad boy out for a spin. Feels much better. Better acceleration from a stop and it doesn’t feel like it is sucking wind just to carry me lol

Nothing I didn’t know.

The things that make us worried and sad can be complicated and seemingly impossible to straighten out.

But the things that make the riders among us happy can be the simplest things in the world.

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