| Author | Message | ||
     Buellfighter |
Okay, I've asked this question before and received some good suggestions on why my S1 is vibrating on acceleration. The responses recommended I check the isolaters. Well I changed the front and rear isos and checked the anti-torque mounts and even checked the frame completely, but I still have this major vibration only on accel. in every gear. Once at cruising speed she's as smooth as butter. I pulled the primary cover and all (looks) well. It's a violent vib. only on accel. More suggestions please!!! | ||
| Henrik |
At what RPM point do you start accelerating hard? If you start too low you're lugging the engine, particularly if you try accelerating from low RPM at Wide Open Throttle. Part of the story as I understand it is, that when you whack open the throttle the air velocity through the intake goes down, which in turn causes poor atomization of the fuel = rough running. Anyway, post a bit more detailed info and maybe we can come up with an answer. Henrik | ||
| Buellfighter |
Henrik, it happens at any rpm when the throttle is whacked open and engine is under an immediate load but then smooths out as load decreases. It is a violent vibration felt mainly at the handlebars. I've owned the bike for five years and am just now experiencing this!? | ||
| Buellfighter |
Maybe a bit more info, Engine seems to run fine, no loss of power or any noises. It is a vibration that feels like a broken motor mount. Isos have been changed and every mounting point checked! In neutral it revs, feels and sounds normal. While in neutral I can slowly raise the rpm and then feel a slight vibration at, I'm guessing (no tach), around 2000. It gives the feeling of a loose primary chain but I've checked it and the play is normal | ||
| Akbuell |
Heavy vibration under load, and fine otherwise. Hmmmm..... Final driveline issue? Loose/worn primary sprocket (Esp fitment of sprocket to trans output shaft)? Missing/worn teeth on anything? Just a thought. | ||
| Buellfighter |
Akbuell, I run a chain and looks good. I have checked the torque on the flywheel sprocket but will check the primary sprocket. I have checked it to make sure it isn't loose but haven't correctly torqued it. I will! Thanks for the help everyone! | ||
| Henrik |
Just a thought: http://www.badweatherbikers.com/buell/messages/32777/155801.jpg It may be a stretch, but does it sound/seem like it's pinging? Carbon build-up on the pistons? Henrik | ||
| Buellfighter |
Henrik, one of the first things I checked was the torque on the flywheel sprocket nut and no probs there. No, no noises, well...other than the obvious! | ||
| Bomber |
did this vibratory action start soon after a mod you performed? always there? building slowly over time? the Isos can look fine, but be shot -- the rubber ages and looses it's elasticity -- | ||
| Buellfighter |
Bomber, vibration seemed to be all the sudden. No mods performed! All isos changed! | ||
| Henrik |
I'm running low on ideas .....  Henrik | ||
| Firemanjim |
Check all motor mounts for cracks/movement and see if one of the tie-bars is loose or damaged.They are consumables and will wear out.Take a look at output bearing area. | ||
| Blake |
Secure well the bike on a wheel stand and see if you can replicate the vibration as you run it through the gears. More better would be to put it on a dyno to replicate and diagnose the issue. Check exhaust tract and all its supports/brackets for good tight connections. Try replacing the rubber bushings with neoprene ones. American Sport Bike provides them. | ||
| Whodom |
Well, since you're checking everything, how about the steering head bearings? Loose bearings first showed up as increased handlebar vibes on my 83 Honda Ascot. Easy to check and correct if that's it. | ||
| Henrik |
Did we talk about the washer on top of the front motor mount yet? It's D-shaped and the flat part of the D needs to point forward so the washer clears the frame. If that washer rotates (it shouldn't) or was not installed as described, the washer will knock against the frame and cause some vibration. Henrik | ||
| Johnnylunchbox |
Bad spark plug wires??? Or spark plug wire boot not seating properly. Just a thought. | ||
| Mmmi_grad |
Id say ignition timing problem or flywheels need retrued. | ||
| Buellfighter |
Okay, here it is! I'm not to proud to admit I screwed up. When the vibration started I knew the front iso was bad so I changed it. Well the vibration was still there so I changed the rear isos and still vibration. After checking every mount on the bike I was thinking motor problem and even looked inside the primary. Well alittle while ago I went to the garage and grabbed a flashlight and was checking the front iso when I noticed the flat side of the "D" shaped washer wasn't perfectly flat next the frame. I guess when I tightend the nut the washer must have spun with the nut and I didn't notice.  Anyway once I reset the flat side to frame the vibration is gone. I remember Henrik mentioning the washer in another thread so I thought I would double check it and sure enough, then I come back from my ride and see he just posted it here! Thanks to all for helping me with this!! It runs like new! | ||
| Court |
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| Henrik |
Excellent news Keith - glad to hear your all set and happy again. Mean looking ride btw. Glad we could be of help. Henrik | ||
| Bomber |
Keith -- that's GREAT -- remember to yell at your mechanic -- very satisfying -- I yell at mine alla time, then generally give him some scotch to make up for it Signed Bomber (spinning my own wrenches since the Johnson administration ;-} ) | ||
| Buellfighter |
Believe me Bomber, the mechanic has been punished enough. Between my friends and posting the truth here, stick a fork in me! We celebrated with a trip to Hooters for a cold beer and scenery!  Good to see Court posting!! | ||
| Firemanjim |
Dang,Bomber,I knew you were a bit long in the tooth but had no idea you have been around since Andrew Johnson????  Hi Court. | ||
| Bomber |
yeah, it's amazing what clean living will do, ain't it? | ||
| Oldog |
 I knew you were a bit long in the tooth but had no idea you have been around since Andrew Johnson????} Hello Mr Canfield.. (Message edited by oldog on June 27, 2006) |
