Motoman's Correlation: Carb Sync. Vs. RPM's

[IanDMacDonald]

It's my observation only. If you're stating it's some act of God causing my rpm's to be higher in-relation to a poor sync., then so be it. However, I don't believe in coincidences, and I don't think that it's a coincidence that my rpm's rise with a bad sync., and lower with a good sync . . .

[dbeardslee]

It's my observation only. If you're stating it's some act of God causing my rpm's to be higher in-relation to a poor sync., then so be it. However, I don't believe in coincidences, and I don't think that it's a coincidence that my rpm's rise with a bad sync., and lower with a good sync . . .

I think what Ken was saying is the gauges are more suspect than an actual change in rpms at a given mph - since that's basically physically impossible if the clutch isn't slipping.

[IanDMacDonald]

I think what Ken was saying is the gauges are more suspect than an actual change in rpms at a given mph - since that's basically physically impossible if the clutch isn't slipping.

Well, if anybody is willing to back me up and confirm my observation . . .

Somebody please take their carbs out of sync., and observe the rpm vs. speed. On my part, I will record my bike in it's current state (bad tune), and re-tune the carbs early tomorrow morning and check the difference. Give me a day or two.

[dbeardslee]

Well, if anybody is willing to back me up and confirm my observation . . .

Somebody please take their carbs out of sync., and observe the rpm vs. speed. On my part, I will record my bike in it's current state (bad tune), and re-tune the carbs early tomorrow morning and check the difference. Give me a day or two.

IDM, I think you're missing the point. If you could peddle the crank it would still require the same rpms on the crank to reach the same rpm at the back wheel. It's a gear train. But the gauges that measure the mph's and rpm's are much more suspect in terms of changes.

Look at it like this - no matter how much power is applied to "A", "C" will always be turning at 120 rpms when "A" is at 60 rpms.

[IanDMacDonald]

Here is the bike last night with a bad sync:

https://youtu.be/_sLLVN3Q0BA

75mph @ 5k.

Good sync., it reads 80mph @ 5k.

[ViperRon]

You know it all depends on your view of things and getting in sync reduces IBJ To get a good view of things your distractions need to be removed and being out of sync defiantly creates distraction. This little exercise shows how much IBJ can easily skew some peoples perspective even to the point of SB syndrome. I get in sync and try not to worry about what I see when IBJ causes SB syndrome.

[MPittma100]

Space/Time

It does that because when the engine is out of tune it throws a wrinkle into the time space continuum that causes the STEEL crankshaft to turn slower than the STEEL main shaft because flux capacitor that connects them becomes distorted and can't operate at warp speed.

Nanu nanu

Simple

Amazingly, after much rocket scientific calculations, I have arrived at the same conclusion Greg.

[motoman]

Amazingly, after much rocket scientific calculations, I have arrived at the same conclusion Greg.

Actually, it's venturi velocity that affects what Ian was explaining. Out of sync you have one or more cyls. 'carrying' the ones with lesser veturi velocity.. Hence the ACTUAL speed difference per given rpm.

[BA80]

Yes, a wrinkle in the time space continuum will cause a solid object to turn slower on one end than the other.

Venturi is just another name for worm hole.

[motoman]

Yes, a wrinkle in the time space continuum will cause a solid object to turn slower on one end than the other.

Venturi is just another name for worm hole.

There's that time space continium again,,,,,,,,,,,,,,,how bout just a few 'lazy' cyls...........kinda like lazy shifting. Besides, you and that banana seat scoot with you aboard, and a couple others need to get out this way again..........end of May through mid Sept. for some REALLY fun, snowless, rainless and break-down riding free mountain fun. Least I'll have to actually 'work' the Venturer a bit sos you all can keep up. Get to LEAST do it in the daylite and not have to folow a tow-truck after dark and in the snow!

[BA80]

The RPMs still won't change travelling through the gears in the drivetrain in relation to wheel speed in any given gear.

Loved the trip out there Brant. Looking forward to doing it again.

Ehhh......snow? I'm from Montana, if snow scares you, you'll spend 6 months hiding. Hell, I've seen snow in July up there.

[XJOK2PLAY]

Aaahhhh....
Just like old times.
Glad things are getting back to normal again.

Good to have ya back, Brant!

Good times............

[Bonz]

Guys, quit it!

IT IS NOT PHSICALLY POSSIBLE FOR RPM AT THE SAME MPH IN A FIXED GEAR SYSTEM (locked in 5th gear) TO BE DIFFERENT BASED ON CARB TUNE OR OTHERWISE. CANNOT HAPPEN!

Are we THAT challenged on this forum as experts on this bike to not understand physics?

Much more likely the air temp was lower or higher and the front tire circumference changed from air pressure variation.

Actually, since it is NOT possible for it to be the state of tune to cause this , it HAS to be the tire circumference or erroneous tach.

Carry on!

[motoman]

Guys, quit it!

IT IS NOT PHSICALLY POSSIBLE FOR RPM AT THE SAME MPH IN A FIXED GEAR SYSTEM (locked in 5th gear) TO BE DIFFERENT BASED ON CARB TUNE OR OTHERWISE. CANNOT HAPPEN!

Are we THAT challenged on this forum as experts on this bike to not understand physics?

Much more likely the air temp was lower or higher and the front tire circumference changed from air pressure variation.

Actually, since it is NOT possible for it to be the state of tune to cause this , it HAS to be the tire circumference or erroneous tach.

Carry on!

Now, THERE'S some space continuum for ya,

[motoman]

OOpps.........got that confused with space cadet.