Unofficial Royal Enfield Community Forum

Royal Enfield Motorcycles => Bullet Electra & AVL => Topic started by: scoTTy on August 23, 2007, 03:26:05 pm

Title: Strange noise
Post by: scoTTy on August 23, 2007, 03:26:05 pm
This just started,, just before I shift to the next gear any gear.. I hear this vibration like noise,

It dissappears after I get past a certain RPM level.. the re occurs at the same spot in the next gears.

Almost sounds like something is loose and hitting .. I can't tell where it's coming from since it doesn't last long.

It only does it while moving..I haved revved the enginge slowly on the center stand,  but it doesn't occur.

The rear chain is within tolerance, It doesn't sound like valves, I thought about pulling the primary cover and checking to see if the primary chain is loose, but I tightened it about 75 miles ago.

Has anyone any suggestions on where to begin My search,,

Thanks,

I'll check back later, I've got to get to work,,

scotty
Title: Re: Strange noise
Post by: justin_o_guy on August 23, 2007, 06:56:43 pm
I had a buzz/rattle on the Guzzi that wouldn't do it sitting still & revving the engine & wouldn't do it engine off coasting down the rough, gravel drive. Went over the bike closely & found a loose spline connector in the shift linkage.
Title: Re: Strange noise
Post by: Thumper on August 23, 2007, 07:18:25 pm
Exhaust brackets or clamps? Other brackets? My turn signals develop harmonic resonance at certain RPMs....
Title: Re: Strange noise
Post by: RagMan on August 23, 2007, 08:10:50 pm
I agree, fender stays, turn signals, headlight housing etc are all capable of having harmonic sympathy with engine revs.  Depending on the tone of the vibration can give you a clue to the location. Is it high pitched, tinny sound, or a deeper tone.  High pitched is usually caused by something short, lower tones by something longer.
Title: Re: Strange noise
Post by: deejay on August 23, 2007, 09:40:51 pm
This just started,, just before I shift to the next gear any gear.. I hear this vibration like noise,

It dissappears after I get past a certain RPM level.. the re occurs at the same spot in the next gears.

Almost sounds like something is loose and hitting .. I can't tell where it's coming from since it doesn't last long.

It only does it while moving..I haved revved the enginge slowly on the center stand,  but it doesn't occur.

The rear chain is within tolerance, It doesn't sound like valves, I thought about pulling the primary cover and checking to see if the primary chain is loose, but I tightened it about 75 miles ago.

Has anyone any suggestions on where to begin My search,,

Thanks,

I'll check back later, I've got to get to work,,

scotty


Is it a rattle/clanging noise? I'm willing to put money on this if you still have the stock exhaust pipe... SAME EXACT thing happened to my bike. There is a botched cat converter welded inside the exhaust, it was rattling in my head pipe at certain rpms. I took off the silencer and used a metal hole saw for a drill and removed it in 2 minutes. Never rattled again, did a plug chop after i removed it, and didn't need to rejet. It bugged the hell outta me for 500 miles, took me that long to figure it out.
Title: Re: Strange noise
Post by: scoTTy on August 24, 2007, 12:46:37 am
this is really driving me batty....I went out and bought a new auto engine stethoscope,mine had dry rotted after 40 years.. still can't pinpoint it and I can get the sound when I rev high enough sitting still .

sounds like ball bearings in a tin can.. kinda of high pitched.. got 2 fans on the engine in the garage.. will check the valves again when it cools down.. yet when I put the scope on the valves it doesn't have that hig frequency rattle..rather quiet matter of fact.. seems like it coming from the front.. can't tell.. I did not check the eccentric cam when I did the 300 mile check.. would this be a possibility.. It only occurs in a small rpm range.. the stethoscope is relatively useless since everything is mechanical.. It seems It might be behind the timing cover.. but I can't tell.. aaAaRgH(http://static.flickr.com/26/97729975_6b24129899_o.gif)


Title: Re: Strange noise
Post by: deejay on August 24, 2007, 12:51:05 am
do you have the stock exhaust system on there???
Title: Re: Strange noise
Post by: scoTTy on August 24, 2007, 01:04:54 am
Yes I do deejay and I read where you said that was where you pinpointed your noise.. I will check that.. You also said you did a plug chop.. what is that?

thanks for your quick reply

scotty
Title: Re: Strange noise
Post by: bwilson17 on August 24, 2007, 01:34:58 am
I once had a strange vibration sound when the engine was higher RPM when shifting then went away when the RPM went down. I tightened all the engine mount bolts and the bolts that held the gas tank in place - That solved my problem.
Title: Re: Strange noise
Post by: deejay on August 24, 2007, 01:36:34 am
Yes I do deejay and I read where you said that was where you pinpointed your noise.. I will check that.. You also said you did a plug chop.. what is that?

thanks for your quick reply

scotty

After I took out the cat converter, i tested to make sure I wasn't running too lean due to removing it. A chop is when you install a new spark plug, get the rpms up and kill the engine under load. then you pull the plug on the side of the road to see if the color is good. It's a great way to see if you are running rich or lean.
Title: Re: Strange noise
Post by: scoTTy on August 24, 2007, 01:48:07 am
Thanks BW.. I'll go check the bolts again since I've had the tank off many times..

and thanks again deejay for your info.. I did notice the rod that holds the footpegs on was awful close to the header.. so I backed it off and then tightened the other side,,

I'll find it or blow it up in the process.. I do have a years warranty if i recall ;) :D ;D
Title: Re: Strange noise
Post by: gapl53 on August 24, 2007, 03:37:53 pm
I have a buzzing vibration in my Electra-X just as I start to disengage the clutch. This happens only at mid-RPMs. Checked everything found nothing wrong. Decided that it was a harmonic vibration when pressure starts to be removed from the clutch plates and they slip.
Also if the last item that was adjusted was the primary chain before this started, I would start my search there.
Title: Re: Strange noise
Post by: No. 5 on August 31, 2007, 01:51:51 pm
My Bike developed a rattle like you describe. I thought it was the valves too, but the more I heard it the more it sounded outside. Went right for the chassis, exhaust and engine stuff. (maybe a loose traficator?) Turns out the vibration dampener weights were loose in the handle bars. Voila!
Title: Re: Strange noise
Post by: rpnix on August 31, 2007, 02:07:48 pm
Another place to look is the chains. I had an odd "playing card in the spokes" noise whenever I backed off the throttle. Turned out that the chains needed to be tightened.
Title: Re: Strange noise
Post by: Kevin Mahoney on September 01, 2007, 09:05:01 am
Sometimes the best cure for a noise in the Bullet is a louder muffler.
Title: Re: Strange noise
Post by: deejay on September 01, 2007, 02:29:59 pm
Sometimes the best cure for a noise in the Bullet is a louder muffler.

Since i'm sure it's the welded cat in the pipe, yup this would fix it! :)
Title: Re: Strange noise
Post by: scoTTy on September 01, 2007, 03:04:15 pm
well I bought another exhaust of ebay, we'll see.  when I had the old one off, I looked into the pipe and everything seemed intact. I have readjusted the primary..checked out for anything loose under the seat. thought maybe it was the side stand but it's tight.

I checked the weights, the rear chain is adjusted..

Thanks for the input..  still haven't found it.. but it doesn't seem to be as bad.

I riding to work today , so we'll see
Title: Re: Strange noise
Post by: RagMan on September 01, 2007, 03:52:26 pm
I gave up trying to identify the noises my Oily makes - it keeps on going, so I tune out the clatter, rattles, and vibrations.. Or at least I do when I can start the thing.
Title: Re: Strange noise
Post by: luoma on September 02, 2007, 01:43:55 am
Loud exhaust works for me too. With the stock muffler, the noises the bike made scared me.
Title: Re: Strange noise
Post by: gapl53 on September 02, 2007, 02:31:52 pm
I gave up trying to identify the noises my Oily makes - it keeps on going, so I tune out the clatter, rattles, and vibrations.. Or at least I do when I can start the thing.
I agree this is the way it was meant to run a Royal Enfield. Don't worry about the little annoyances as long as it runs. That how it was in the old days.
Title: Re: Strange noise
Post by: prof_stack on September 02, 2007, 05:23:20 pm
My former Harley Electra-Glide had a similar noise as you described.  Turned out the baffle in the aftermarket "Screaming Eagle" muffler needed to be rewelded "every so often".  That worked, but eventually I put on the originals, discovered that a little more back pressure meant better low end pull (at least on this Hog), and loved the quieter exhaust note.

Hopefully your noise will go away or else that you learn to not hear it!   ;D
Title: Re: Strange noise
Post by: gapl53 on September 03, 2007, 03:15:10 pm
My former Harley Electra-Glide had a similar noise as you described.  Turned out the baffle in the aftermarket "Screaming Eagle" muffler needed to be rewelded "every so often".  That worked, but eventually I put on the originals, discovered that a little more back pressure meant better low end pull (at least on this Hog), and loved the quieter exhaust note.

Hopefully your noise will go away or else that you learn to not hear it!   ;D

Back pressure to a point will always increase low end torque. The more open the pipes, means the horsepower will move closer to the top of the RPM, sometimes with a loss of torque. Sometimes you can even move it pass the safe RPM limit of the engine. Straight pipes or drag pipes will do this often, especially on low peak RPM engines like the H-D or Enfield. People think they are going faster than they are because of the noise created. I always outrun my buddy's Screaming Eagle equipped Road King with my stock Electra-Glide Classic even when I'm two up and he's single. Drives him nuts, he won't believe mine is stock.
Noisier is not always better.
Title: Re: Strange noise
Post by: hoppyre on September 04, 2007, 12:44:53 pm
This just started,, just before I shift to the next gear any gear.. I hear this vibration like noise,

It dissappears after I get past a certain RPM level.. the re occurs at the same spot in the next gears.

Almost sounds like something is loose and hitting .. I can't tell where it's coming from since it doesn't last long.

It only does it while moving..I haved revved the enginge slowly on the center stand,  but it doesn't occur.

The rear chain is within tolerance, It doesn't sound like valves, I thought about pulling the primary cover and checking to see if the primary chain is loose, but I tightened it about 75 miles ago.

Has anyone any suggestions on where to begin My search,,

Thanks,

I'll check back later, I've got to get to work,,

scotty

Hey Scotty, had the same noise on my Bullet 65, would only show up at 45 mph in top gear. Turned out to be the chain guard viberating bad enough to hit the left shock. Tightened all the guard bolts, and bent the rear bracket a little. Hope this helps.     Mark