Flash 3.26

[Wheelman-111]

Greetings:

Ok Bear, I'll go out and test, just because of your teasing. If I get picked up in a vortex, it'll be your fault! And you can't have my engine!

Just to add another humorous note, my petcock seems to have failed. Last time I pulled the carb - it was last night, fer cryin' out loud - all was fine. Now I'm getting The Flood. Had to put a hemostat on the fuel line to avoid setting the apartment complex on fire. I've gotta check if I have some Sea Foam or somesuch handy.

Maybe I'll get lucky and the spooge'll clear itself. The inline filter goes on tonight, that's for sure.

[Bear45-70]

Greetings:

Ok Bear, I'll go out and test, just because of your teasing. If I get picked up in a vortex, it'll be your fault! And you can't have my engine!

Just to add another humorous note, my petcock seems to have failed. Last time I pulled the carb - it was last night, fer cryin' out loud - all was fine. Now I'm getting The Flood. Had to put a hemostat on the fuel line to avoid setting the apartment complex on fire. I've gotta check if I have some Sea Foam or somesuch handy.

Maybe I'll get lucky and the spooge'll clear itself. The inline filter goes on tonight, that's for sure.

I once drove a Sedgwick County lineman's truck thru a major really bad thunderstorm with down pours that caused me to finally pull over and wait it out. Unknown to me that storm spawned 3 tornadoes. All missed me, just pure luck. Oh and the county seat for Sedgwick County is Wichita, Kansas. So I was a Lineman for the County.

[Wheelman-111]

Greetings:

Another embarsasing Tuner story to share. Having drilled the "100"/97 to a true 101 I set out, prodded by The Bear's ridicule and at Great Risk of Personal Injury or Death to test said jet. Hmmm, a bit burbly at below quarter throttle, but better accel for sure. Best of all CHT now staying below 350. Raising the clip to middle notch should lean things nicely. It did. In fact the midrange sweetness was back!

So confident was I in my setup that I decided to reinstall the rear plastics, after riding all week nekkid. Thereupon I discovered the unconnected bystarter plug. Now I know the BS circuit's contribution to the melange above idle is modest, but dang it all!

I'll see how it runs and what temps I get later. Maybe I shouldn't work in the rain and lightning? (although the lightning did provide amazingly good light, it didn't seem to last very long. Good thing the strikes were coming about every 5 seconds...)

Setup is UNI pod, 101 in stock carb, middle clip position, 7g Polini rollers in the Polini vario. 78cc not yet allowed over 8K. Well not much anyway . Only 2 hours on the bore.

[Wheelman-111]

Greetings:

Well, the bystarter contributes more to the mix than I'd originally believed. With its plug connected and a true 101 jet in place, the temps rose again this morning when it shut down the enrichener passage. Not too scary, but 350-400 without any throttle abuse. I'm going to try out the 103 again and see if thatt decreases temps without being too rich once it's no longer receiving the unwanted bystarter contribution.

Lesson: Live, learn and pay attention to the simple stuff.

[Wheelman-111]

Greetings:

The 101 to 105 swap improved temps some, but the needle still swung north of 400 briefly when releasing throttle. Still no burbling, either.

I can now drop the bowl and swap jets without removing the carb. This just required removing the airbox holder bracket whose only other apparent purpose was to prevent the user from dropping the bowl...

Drilled out to 109, (#57 index, if you're keeping score) and finally saw temps at or below 350 for more than half the time. An odd midrange burble and a touch softer on top told me it was close enough. The needle only approached 400 when the throttle was snapped shut after 20 seconds' WOT.

Speedometer needle assumes the horizontal position faster than Madonna backstage at a Chippendales show. Remarkable for a stock intake and carb, I thought.

The plan is to get another hundred miles/1 more hour logged before I pull out the GPS and see wottle she do.

I'm after temperature stability and engine longevity with an accessible 55, maybe tops at 60. With the wind, of course.

If the stock carb won't do it, there's always this:

[Wheelman-111]

Greetings:

Good morning, kids! In our last episode, a smug Wheelman was ever so certain he'd found the 109 to be the Magic Jet for the stock carb with the 78cc setup. Comfortably cool during testing last night, even after a good spell at WOT. So we're done until break-in stage is over, right? Maybe Not!

Now this morning, with ambient air temps easily 15 degrees cooler, it's running warmer again. Pretty much stuck at 370-400 at steady-state cruising and without throttle abuse. What makes an engine run 325 at night and 375 the next morning? Humidity?? I need to tune for average conditions, so I'll break out the drills again tonight and perhaps move the needle clip down again... Sheesh!

[Wheelman-111]

Greetings:

For the few who decided for whatever reason to stick with the stock carb on a big-bore application, I offer the following:

Stock airbox can be a challenge to adapt. The bike can work, but it's hard to get it to run well, even harder to exploit the full potential of the 72+ cc bore kits.

The UNI open pod filter works fairly well but is loud. My Arreche "Octopus" is a little more muffled:

Lurking inside is a home-made "adaptor" consisting of a 2" length of clear Polyurethane hose, whose wall thickness adds enough to the 28mm carb bellmouth to match the Arreche's 35mm donut. The length of the hose can be "tuned"; an ongoing experiment.

JETTING: The 109 ran well - a few burbles and episodes of 4-stroking - but I felt it was still too warm, especially in the humid Deepinnaharta mornings. A calculated gamble to drill it out to a #56 Indexing drill - measured out to a 112 diameter - FAILED! It started and did OK until the throttle was opened. Thereupon it burbled and smoked and had little-to-no power. It didn't run long enough to allow the bystarter to close, but regardless, I had to get to work. I didn't have time this morning to lower the needle a clip or two, which I may try before swapping jets again.

Sounds like the ideal jet is around a 110 with my current setup, doesn't it?

Here's Flash Scootertrash III as of today:

[burnt_toast]

hmmm you "offer" the following, as in FOR SALE?! If so I'll take it haha although I doubt that is the case

Lookin mighty hot hot hot in that last pic

And now I think you SEE why I hate tuning stock carbs, they can be very efficient and maybe even net similar goals I'm seeing on my "budget built" Bumblebee stage2, but HOT DANG tuning okay carbs is a breeze with jets readily available

[Wheelman-111]

Greetings:

Will the OKO carb ("okay") fit with side skirt installed?

[bakaracer]

With a ct manifold you need a filter with a 45 deg angle connector on it or if using a airbox of some type.The carb and manifold itself will clear the sideskirt.

[Wheelman-111]

Greetings:

Thanks Mr. Bakaracer! I'll never cut my panels. (Again... )
Uni makes an angled filter or two. I'll wander over there if I ever get ta' hankerin' for more carburetion.

I have to say the Nik 78 scoots away pretty dang good for a bike with a stock carb. I have now had the needle pointing flat to the right a couple of times - below the "mph" on the speedometer - and that comes up in under 1/8 mile. Flash II, with 65cc could do it too, but it took a much longer run-up. I may be a bit under-geared with 9:1, but I'm liking the around-town "slingshot" effect. It's at least as quick as most "normal" drivers getting away from traffic lights.

[Wheelman-111]

Greetings:

Setup: 2001 Elite SR
DayWot's Nikasil 49mm
Arreche Filter, stock carb jetted to 109
Stock intake.
V8 exhaust
Polini variator 7gs
Stock Center Spring!

Runup: not yet ready to hold WOT for too long. Still iffy CHT

Humid, foggy actually in 80 degree evening.

I put an extra oz of oil in the tank and set out with the GPS to see what kind of speeds were readily accessible.

Result: 52.3 with remarkably little drama. This in less than half a mile. The variator had just maxed out when I saw the patrol car on this 45MPH street so I backed off. No flashy lights. My gauge read a hair over 350 and Mousewheels and I believe this actually means closer to 300 due to incorrect thermocouple.

The jetting still feels pretty rich, so there's more tunin' to be done! I'm pretty happy so far.

[Wheelman-111]

Greetings:

See above post for the latest change:

The 109 left a relatively new BPR7 HS plug pretty black. I installed the gauge-correct TRW Type "J" thermocouple and saw average temperatures 80 degrees cooler. 275-375 degree peaks, which is probably a lot closer to the truth. Nickel Silicon or not, his bore wouldn't still be running if the 450-500 peaks previously shown were true. The piston's still Aluminum...

Installed Brad 3's Daytona 110 jet (which actually measured a stiff 106 bore diameter...) Running a whole lot better through the low-end. Much much stronger pull up top, and (best of all) 350 and under most all the time. Never touched 400 - at all.

I'll pull the GPS out this evening and confirm what a stock carb can really do.

[devenex]

Just curious, any idea on the mileage your getting? I imagine using the stick carb should give better than a larger aftermarket one.

[Wheelman-111]

Greetings:

Cutting to the chase:

The upper right corner tells all she wrote today. Double-nickel only with flags adroop and 68 degrees ambient. This came up in about a half-mile. Mirrors were on.

The good news is it doesn't grenade, despite riding like I stole it. The speedometer underlined MPH

-straight across - so the speedometer itself is useless above ~55.

I'm philosophical about this speed. For sure there's more to be had with further transmission tweakage. I have a longer, wider belt I can try which will ride both rims of the pulleys. The engine's basically loafing, with the inherent durability that implies. Note the temp after the climb up the parking garage. It never hit 400 and spent most of the time at 325-350. Oddly it continues to show highest temps cruising 35 at low throttle openings. The needle drops when the throttle is opened wide before slowly climbing back to peak @~375 again.

That said, it's nagging me that Flash II demonstrated faster speeds. D'ya think the engine's wasting power bending the speedometer needle? How much more can I get from an OKO or this:

Then again, do I need it?