Carby sync

[creeture3]

Hail fellow troubadours, I am intending to sync my ( the ST's)  carbutators. Question: how are the carbs numbered ? #1 front left, #2 rear left #3 front right #4 rear right??

I am experiencing vibrations at touring speeds , starts at 110ish and continues to 130 + , nothing drastic, just No longer getting that turbine smooth cruising and can't seem to be able to "drive through it" , so that is why I am going to the carbs first.

The bike has done 65K probably without a carby tune, but if anybody has any other suggestions, I would appreciate it.

( I believe the fuel pump tends to go on holiday after a while?? )

Over............

[Brock]

That would be about 3500 revs, there can be a little buzz at that range in top gear.

[creeture3]

That would be about 3500 revs, there can be a little buzz at that range in top gear.

This is more of a vibration than a buzz. I know what you mean tho'

I read somewhere that the carbs should be looked at every 4K or so. AFAIK, that's never been done. Anyway, it can't hurt to look at them. What could possibly go wrong..................

[Brock]

My bike is at 170000 + Ks, no sync or even plug change.

[Yorkie]

Carbs should not require syncing unless they have been played with

[creeture3]

My bike is at 170000 + Ks, no sync or even plug change.

Carbs should not require syncing unless they have been played with

Interesting......

I do have the service receipts from the previous owner, and no mention of carbies anywhere. I have recently had a new front tyre fitted, maybe I should look in that direction.

I must admit it idles fine, runs fine up to about 100k's, and then the vibes start to set in. Doesn't use an inordinate amount of fuel, and zorsts are a nice colour. (blackish) 

aside: I remember when, with leaded petrol, a nicely tuned engine had a nice light  grey zorst pipe.............

I have an old fashioned wheel balance device, maybe I will try that.

[StinkyPete]

As well as wheel balance you may want to also check the following...

Rim out of round or damaged
Wear/Movement in the wheel bearings
Wear in the head bearings
Wear in the swingarm bearings
Worn UV joint in the driveline, which presents as a "buzz" through the frame

[creeture3]

Worn UV joint in the driveline, which presents as a "buzz" through the frame

That sorta feels like it!

Bloody hell, I hope no ! Sounds like a LOTTA hard work..............

But after 65K, and a fairly easy life? Do you know of a way of checking that?

[StinkyPete]

Worn UV joint in the driveline, which presents as a "buzz" through the frame

That sorta feels like it!

Bloody hell, I hope no ! Sounds like a LOTTA hard work..............

But after 65K, and a fairly easy life? Do you know of a way of checking that?

I have  blown a universal joint in the drive at around 135,000km, which showed up as a speed related buzz through the footpegs pegs, and a heavy growl as the suspension unloaded when exiting an undulation.  See  http://ozstoc.com/index.php?topic=10046.0    Pulling in the clutch would change the load on the UV joint and change how it is felt or heard.

If it is the UV joint, you need to attend to it as a matter of urgency.   If it lets go, the shaft will be thrashing around in the swingarm housing, and I imagine it would do a huge amount of damage to a lot of stuff, and could even lock up the back wheel.

[alans1100]

More than likely wheel balance issue having just replaced the tyre; especially if all was well before hand.

Rim out of round or damaged
Wear/Movement in the wheel bearings
Wear in the head bearings
Wear in the swingarm bearings
Worn UV joint in the driveline, which presents as a "buzz" through the frame

I expect that might be the case with mine if I had any unusual vibration since it's done 207,000km.

[creeture3]

More than likely wheel balance issue having just replaced the tyre; especially if all was well before hand.

Yeah, all was good before. I will do a static check on my home-made balancer first  and see what happens.

Stay tuned...................