Vibration

[kirby1923]

Yeah , that's it  ::) ;D

 Kirby , you are the engineer , but my understanding is that relative piston speed (between the pair) can have an effect on balance . In a 90 degree configuration , one piston will be at max acceleration while the other is at max piston speed , either traveling up or down , creating a natural balance factor , correct ? Yeah , we won't even talk about 45 degree designs , a Harley riding buddy of mine used to say they ran by magic  :o :D

  Dusty

Flywheels and counter weights are good inertial dampers and the moments are small. Like the off set, they are not felt until high rpm and at some point will become a structural problem. It would be difficult to reach that point with normal aspiration. Red lines are typically  (almost always) a valve train limit.(except for desmo).

mike :-)

[56Pan]

Well , and right you are , didn't explain that very well . Failed to make the distinction between MG and BMW . Sorry . Still some rocking couple induced shaking at low RPMs due to the slightly uneven forces applied to the crank . Geez , wish I had the math to really understand this stuff  :D Anyway , my point was more to neither airheads or Guzzi engines being known as shakers , despite the fact that both can jump around at idle .
 
 Dusty

Yeah, I understood "offset" to mean something like the big end journals offset on the same crank throw.  There was a Buick V6 that did that back in the late '60's, if I remember it right.  I'm not a bit put out by the vibration from my MG.  Worst motorcycle I ever had for aggravating hand numbing vibration was an '85 BMW K100.  Nothing was loose.  Just the nature of the thing. Was glad to see it go.

[oldbike54]

Yeah, I understood "offset" to mean something like the big end journals offset on the same crank throw.  There was a Buick V6 that did that back in the late '60's, if I remember it right.  I'm not a bit put out by the vibration from my MG.  Worst motorcycle I ever had for aggravating hand numbing vibration was an '85 BMW K100.  Nothing was loose.  Just the nature of the thing. Was glad to see it go.

 Yeah , was never really much of a car guy , but wasn't there an "odd" fire and "even" fire version of the same engine , with maybe a different crankshaft configuration . One was smooth , the other not so much , but the shaker made more power ?
 
 Dusty

[56Pan]

Yeah , was never really much of a car guy , but wasn't there an "odd" fire and "even" fire version of the same engine , with maybe a different crankshaft configuration . One was smooth , the other not so much , but the shaker made more power ?
 
 Dusty

My older brother had the Buick Special V6 without the offset crank throws.  It did shake noticeably at idle and with all firing. Curious now and will have to look up about the other versions of the engine.  Geriatric sleep cycle again, and nothing else to do.

[56Pan]

http://engine.firebirdv6.com/V690.html

There it is Oldbike.

[Two Checks]

The Honda V twin and V four engines used 180 or 360 degre cranks depending on aplication.

A perfect example of an odd fire V6 is the 3.9 liter engine used in Dodge trucks. It shook enough it wasnt offered with a manual transmission. Later versions with better engine management were smoother.

[Kev m]

Okay, I found the Kawasaki 540, aka "Mule", also has a counter balancer, so that's 2 out of 3 in his stable that should be fairly smooth.

I had a 1994 Sportster 1200 and commuted on it regularly (like the OP, putzing around town).  As long as I kept the revs down below 4,000, the vibration was not intrusive.  The 883's supposedly vibrated even less.  On the highway without a windshield, let's just say that your post about your hands falling asleep brought back memories.   ;D

It's good that MotoGoosy has an extra bike to ride while he sorts out his EV.  

Well, not for nothing, but I've been into Sportsters for 20 years, mostly 883 and 1200 EVOs. I've never seen one whose motor doesn't vibrate more than a the Jackal I put 40k miles on.

Even on the rubbermounts, even if you as the rider are mostly isolated from it, you can tell how much the motor is vibrating if you tuck your knee onto the air cleaner.

So to hear that a solidmount hugger 883 vibrates LESS means something is out of whack.

As for whether or not you found your 94 vibration intrusive, the only thing I can comment is that there have always been some owners who claimed Harleys don't vibrate that bad. But to that I'll answer no, that just means your personal level of tolerance for such things is higher than average.

If they didn't vibrate so badly Harley wouldn't have spent millions over the years developing multiple rubbermounted chassis (more than 4 FLHs just in the EVO era, 2 Dynas, the FXRs, the XLs) and added a counterbalancer to the Softails).

It's so bad on solidmounted bikes I've seen light bulbs shaken apart, I've seen pegs or shifters fall off going down the road, I've seen oil tanks crack their welds, I've seen a license plate crack all the way from top-to-bottom.

Hell they vibrated so bad their engineering department developed a standard or measurement utilizing the distance of motion the handlebar grips were deflecting by it.

I would never own another solidmounted Harley EXCEPT as an "around town" bike. Yet, I never gave hopping on my Jackal and riding up or down the east coast the slightest of hesitation.

[Aaron D.]

Seriously, the guy's winding you up.

I did find the '02 EV to be quite different from our Jackal, a LOT more low-end, and vibes were different too, but not sure why.

But even if his bike is broken, he's winding you up

[youcanrunnaked]

Well, not for nothing, but I've been into Sportsters for 20 years, mostly 883 and 1200 EVOs. I've never seen one that doesn't vibrate as more than a the Jackal I put 40k miles on.

Even on the rubbermounts you can tell how much the motor is vibrating if you tuck your knee onto the air cleaner.

So to hear that a solidmount hugger 883 vibrates LESS means something is out of whack.

As for whether or not you found your 94 vibration intrusive, the only thing I can comment is that there have always been some owners who claimed Harleys don't vibrate that bad. But to that I'll answer no, that just means your personal level of tolerance for such things is higher than average.

If they didn't vibrate so badly Harley wouldn't have spent millions over the years developing multiple rubbermounted chassis (more than 4 FLHs just in the EVO era, 2 Dynas, the FXRs, the XLs) and added a counterbalancer to the Softails).

It's so bad on solidmounted bikes I've seen light bulbs shaken apart, I've seen pegs or shifters fall off going down the road, I've seen oil tanks crack their welds, I've seen a license plate crack all the way from top-to-bottom.

Hell they vibrated so bad their engineering department developed a standard or measurement utilizing the distance of motion the handlebar grips were deflecting by it.

I would never own another solidmounted Harley EXCEPT as an "around town" bike. Yet, I never gave hopping on my Jackal and riding up or down the east coast the slightest of hesitation.

One of the reasons that H-D parts are so damn heavy; they have to be "over-engineered" to withstand the vibration.  

I had a friend whose Buell self-destructed when it vibrated a screw loose from the intake and ingested it into the engine.  Kablooey!

[Kev m]

One of the reasons that H-D parts are so damn heavy; they have to be "over-engineered" to withstand the vibration.  

I had a friend whose Buell self-destructed when it vibrated a screw loose from the intake and ingested it into the engine.  Kablooey!

I'm acquainted with a few Harley engineers.

There's another reason their parts are so heavy at times. Liability from really dumb lawsuits.

Like the 300# guy who sued them after he decided to use the brake lever on his bike as a step stool to get something on a shelf in his garage and was surprised when it snapped and cut his leg badly.

So they've got some ridiculous standards for components like that.

[Triple Jim]

Yeah, I understood "offset" to mean something like the big end journals offset on the same crank throw.  There was a Buick V6 that did that back in the late '60's, if I remember it right.

And all Chevy 4.3 liter V-6 engines, derived from the 350 V8:

[kirby1923]

And all Chevy 4.3 liter V-6 engines, derived from the 350 V8:

Required for a more even firing order in a 90 degree V 6. GM had a 60 degree that did not require this but it was smaller capacity and GM wanted to use the off the shelf components of the small black V 8 as much as possible.

I believe that they even have a balance shaft now that runs down the center of the block to further smooth it out.

mike

[Chuck in Indiana]

One of the reasons that H-D parts are so damn heavy; they have to be "over-engineered" to withstand the vibration.  

I had a friend whose Buell self-destructed when it vibrated a screw loose from the intake and ingested it into the engine.  Kablooey!

I was on a trip with Harley Bob when his Softtail broke the 3/8" mounting bolt for the rear turnsignal. (!!) Now, that's some serious vibration..

[LowRyter]

I hope this thread gets blowed up and swept out.

[MotoGoosy]

Already has.  I simply stated that my Guzzi vibrates far more than any other bike I've ridden.  This is confirmed through many sources, hence the moniker, "A small but loyal following".  I just wondered if mine vibrated more than the average Guzzi.  Answer from the experts at the dealer and shop is No, it's normal to run like a tractor.

[rocker59]

Locked.  This thread has run its course.

 :+=copcar