3750 - 4200 Harmonics - Shaft drive

[salty_monk]

Getting an annoying "jingle" on the GS1100G, only at those specific revs. Nothing before or after. Not tried it stationary as yet but wondered if anyone else had had the same nd found it.

Sounds like it's at the head of the bike somewhere.... prob under the front of the tank is my guess but might be something on the triple...

I've had Dyna Coils rattle against the tank underside before but this sounds more "bundle of keys" than that - plus I have stock coils on this one.

(It's not my keys, using a bare key on this bike currently, no key ring at all...)

 

[LAB3]

Detonation? How do your plugs look?

 

[Steve]

Headlight trim ring?

Fender rivets?

Loose (unrestrained) connectors inside the headlight bucket?

Loose hardware on back of instrument cluster?

.

 

[salty_monk]

Yeah, all good suggestions. Pretty sure it's not detonation, it does it in all gears at any load as long as the revs are right

It could be something in the bucket although it's all pretty tightly packages. My guess is that it's the metal fork cover probably, the one that covers the lower clamp bolts..... I'm guessing temporarily shoving some foam up inside it will probably tell me if that's the case...
It's definitely the RPM when the bars have the most vibes in them too.

 

[Big T]

Horns!!
Vibrating on their stalks under the tank

 

[salty_monk]

Horns horns horns :lol: I'll take a look there too... thanks!

 

[Steve]

Vibes? :-k

Now that you have a few "break-in" miles on it, double-check your valve clearances and carb sync.
For some reason, the 1100s seem to be rather sensitive about that.

.

 

[salty_monk]

Yes that will be on my list.. I planned to do it all at Head gasket re-torque & oil change time, about 500 miles.

Got about 65 on it now, still on the first tank of gas! It goes well though! The carbs (you serviced last, I just did a refresh) seem to be working well. Nice even temps across all pipes (measured with a laser temp gauge)

 

[Redman]

Doesn't fitt your description of suspected location, but "rattle of keys" reminded me of the cam end caps. Easy enough to check.

 

[salty_monk]

Yep another one to look at.. thanks. It's definitely a higher pitched jangle sound not a knock.

 

[Brendan W]

Fuel tank cap?

 

[salty_monk]

One I hadn't thought of... thanks

 

[salty_monk]

Turns out that this is the metal cover on the lower triple.

I think the fix is to bend the round fork loops on the headlight tabs out a bit to make them effectively longer so that they apply more pressure to it... Front fork legs will need to be slid down out of the way to do so though.

Kind of a big job to cure a noise!

 

[Grimly]

I threw mine away years ago. Pointless bling.

 

[bwringer]

I love a good solved mystery...


- On the GL models with a chrome front fender, I've found that the rivets can get a wee bit loose and cause all sorts of odd unseemly clanks. You'll have to remove the fender and give the rivets a couple of hard bangs with a large hammer to expand them slightly and stop the rattle. Figuring out how to support the other side of the rivets and keep from damaging the finish on the rivet is a tricky exercise in fixturing... IIRC, I used a piece of something softer like copper or aluminum as a shield between the hammer and the chromed rivet.

- A friend on a totally different bike once came to me with a complaint of a disturbing clunk on braking. All sorts of exotic and expensive possibilities were running through his head. After a lengthy search, the culprit was a "gremlin bell" some well-meaning auntie had given him a while back. Not wanting to cause offense, he had installed the bell on his crash bars with a twist of wire while she looked on proudly, then promptly forgot all about the stupid thing. The bell, I mean. Over time, the bell had migrated into a position where it could gently bonk against the front fender when the suspension was compressed.

 

[salty_monk]

I solved this one by putting my finger on it whilst driving down a straight empty road at 4k ish rpm's.. Luckily there are a few more empty roads at the moment

 

[93Bandit]

I love a good solved mystery...


- On the GL models with a chrome front fender, I've found that the rivets can get a wee bit loose and cause all sorts of odd unseemly clanks. You'll have to remove the fender and give the rivets a couple of hard bangs with a large hammer to expand them slightly and stop the rattle. Figuring out how to support the other side of the rivets and keep from damaging the finish on the rivet is a tricky exercise in fixturing... IIRC, I used a piece of something softer like copper or aluminum as a shield between the hammer and the chromed rivet.

Thank you! You may have just solved a noise that's been bothering me since day one!