Whats that noise?

andreaskfk

andreaskfk

Joined
May 7, 2024
Messages
3
Age
33
Location
Sweden
First of all i would like to apologise for the bad English spelling and gramar (im swedish)
Im new to this forum and this is my first post

so now to the point
I have a noice from my st1100 i just got :/
Its a knocking sound.
I hear it from the front of the engine AND the rear but i think its more noticible from the rear
And of my gueses are correct its from the gearbox.
A lot of people say this bikes makes alot of noice just ride dont think so much. But i want to be sure so i turn to the true proffecionals you guys

link to video with sound
 
If you think it's the gear box pulling the clutch should change the noise, carbs out of sync can cause some type of a knock noise. Gear box highly unlikely. Clutch drum maybe. It's old if you start looking for trouble you might find it. Sync the carbs and ride it.
 
First, @Uncle Phil was being modest. He is trying to corner the market on 1100's and has 8 - half of them are a gold mine of parts to support his running 4 bikes.

I never owned an 1100 (mine was a 1300), but after a bad experience at a dealer, an independent mechanic taught me a lesson. A discount tool place on this side of the puddle sells a mechanic's stethoscope for $8.00 USD. You can do the same with a long hardwood stick, screw driver, or metal rod held up to your ear. By touching the other end of the stick (or the stethoscope) to various parts of the bike you can localize where the sound originates. The dealer's tech did not use one of those, and cost me $650; the independent mechanic did, diagnosed the problem and explored how serious it was and charged me under $200. He told me what part to buy for $100, and to change it myself. Two lessons learned.
 
There's no knocking there. The engine sounds a little out of balance - the carbs. Before you do them, make sure that you don't have an exhaust leak at one of the three joints - the left and right silencer / muffler and the joint a bit further forward where the left hand and right hand pipes meet up.

Just hold your hand near to the joints - you'll feel the pulses of gas if there is a leak.
Or if it has just started up, you'll see the exhaust. Don't breathe it in !

The engine is struggling a bit as it warms up, which is exaggerating the uneven sound, you need to reduce the choke as it gets warmer.
 
You not being use to your ST1100 probably will find some noises alarming. But remember these are 20 plus something year old motors and they are not going to purr and run very smoothly like they did when new. I'm in the just ride it crowd:dr11:
 
Hi guys! Thanks for all the reply’s! Today I put on the airbox and tried some things, and I figured out that the sound changes when I pull in the clutch! It don’t disappear but it gets a little quieter, I can also feel vibrations in the clutch lever that matches the sound. What could it be?
some kind of bearing? Hard to replace yourself? I work in cars a bit so I’m not completely useless with a wrench ;)
Thanks again
 
@andreaskfk , welcome to the forum.

Congratulation for your ST1100. And speaking of your ST1100, wich year is it ? Do you have a lot of mileage / kilometers on it ?

In 2020, I bought a 2000 ST1100, with only 32000 km / 20000 miles (an average of 1000 miles a year). It had spent some years without running much, for sure.

So, when I first started it, it was running a bit rough, the smell of the exaust was terrible, like burning carbon deposit in a chimney fire, I had black smoke, etc.
I took the gas (how old ?) out from the tank and replaced it with fresh new gas.

After I ran it for a few hours (an hour or so every day, as time permitted) and after about 2 complete gas tanks, I noticed my ST1100 was running much better, really.
Not only the engine, but also the clutch and the shifter. I often had hard time, at the begining, to engage the first, and often a "clunck" was audible when I was shifting gears.
It all went better after a while.

Now... I listened to the sound of your engine, in your video. The only time I hear something... just a little strange... is when you are filming near the radiator.
I hear something like thin metal sheet vibrating. It is subtil, not much...
I suspect it could be, maybe, the heat shields. They protect the "plastic" fairing from the sometime intense heat from the exaust exiting the cylinder heads.
I have read that the little screws that hold them becomes rusty sometimes and it makes them vibrates a bit.
Other than that... your engine sounds very good to me. Very much like mine. OK... Maybe not as good, but very close. ;)

heatshield.jpg

By the way, english is also a second language to me. My mother tongue is french, like almost all people here, in Quebec.
So, I'm certainly making mistakes with my english, but people are older and mature here. We are all riders trying to help each other and you'll find new friends. ; -)

Christian
 
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