Rattling carburetors

[Reinhoud]

Anyone here experienced rattling carburetors on their GS / GSX with CV carburfuckingettors?

 

I have a rattle, and I don't think it's the engine.

Rattle follows the valve train revs, sounds more plasticy then metallic.

As soon as I go off the throttle it's gone.

It's louder in 4th gear at 80 than 5th gear at 100

Gone when I open up the throttle more

 

 

Do carburetors from a Bandit or GSXR fit, or can be made to fit, on a GSX1100 / GS1000?

 

Thanks

[Dezza]

Dunno about the rattle but oil- and aircooled engines have the same inlet spacings so oil-cooled carbs can be relatively easily mounted on an aircooled engine. Rubbers, tank and tap clearance and jetting will depend on carb/engine/chassis combo .

[Blower1]

Piston slap? It not sound so metallic and dissappears when engine have more load.

My first "big bore" cylinder block did that because the piston to cylinder wall clearance was slightly over 0,10 mm.

 

[Reinhoud]

 I've got a 1247cc big bore on my GS1000, JE pistons and the recon company stuffed up, so I have a lot of piston clearence, more then 0.10mm.

JE made the pistons too big for the bore size I provided, and the piston clearance they recomend, and then the recon company machined the vore a bit bigger then the maximum clearance JE recomends..

 

Which more modern Suzuki has a 34 or 36 mm carburetor?

Edited November 11, 2023 by Reinhoud

[Dezza]

BST34 = slabby 1100, powerscreen 1100; BST 36 = 1200 blandit, GSXR 1100k,l; GSXR750 j,k; 750 teapot. Variations within carb type, even when size is the same. See sticky in oilcooled .

[Gixer1460]

1 hour ago, Reinhoud said:

 I've got a 1247cc big bore on my GS1000, JE pistons and the recon company stuffed up, so I have a lot of piston clearence, more then 0.10mm.

JE made the pistons too big for the bore size I provided, and the piston clearance they recomend, and then the recon company machined the vore a bit bigger then the maximum clearance JE recomends..

 

Which more modern Suzuki has a 34 or 36 mm carburetor?

Bad recon co.! With hindsight you should have thrown them back with a ' you've f**ked up, you're paying for new liners! ' Any carbs are now going to be close to 20 yes old so will be a gamble whatever you find!

[Reinhoud]

20 year old carburfuckingettors will be 20 years younger as what's on it now

 

I'll see if I can find something useful..

[Pedda]

What do you run on the intake side of your mixer? In case you still have the stock airbox, you might want to get rid of it because tricky to match bandit carbs or similar. Double k&n pods kinda work well.

[Reinhoud]

6 hours ago, Pedda said:

What do you run on the intake side of your mixer? In case you still have the stock airbox, you might want to get rid of it because tricky to match bandit carbs or similar. Double k&n pods kinda work well.

It's turbocharged

[Reinhoud]

On 11/11/2023 at 6:13 PM, Blower1 said:

Piston slap? It not sound so metallic and dissappears when engine have more load.

My first "big bore" cylinder block did that because the piston to cylinder wall clearance was slightly over 0,10 mm.

 

How loud was your piston slap?

[Blower1]

It was not so loud. It was audible up to highway speeds.

The sound was softer than in connecting rod big end bearing damage.

The sound disappeared for a while when the engine was loaded more heavily ( the pistons expanded more than normal).

[Reinhoud]

14 hours ago, Blower1 said:

It was not so loud. It was audible up to highway speeds.

The sound was softer than in connecting rod big end bearing damage.

The sound disappeared for a while when the engine was loaded more heavily ( the pistons expanded more than normal).

Thanks, could you hear it on idle?

[Blower1]

7 hours ago, Reinhoud said:

Thanks, could you hear it on idle?

It was audible on idle too.

If you going to lift the cylinder head, check that head gasket not cover the cylinder bores. If it covers, piston can "kiss" the gasket edge in the tdc. That can also be reason for piston slap. I had once head gasket where one cylinder hole was 1mm offset.

[Reinhoud]

15 hours ago, Blower1 said:

It was audible on idle too.

If you going to lift the cylinder head, check that head gasket not cover the cylinder bores. If it covers, piston can "kiss" the gasket edge in the tdc. That can also be reason for piston slap. I had once head gasket where one cylinder hole was 1mm offset.

Thanks.

 

I don't hear it on idle.

But I've got straight cut primary gears, that rattles like hell on idle..

Edited November 19, 2023 by Reinhoud

[Gixer1460]

Er ! Primary shouldn't rattle - ever!

They do make a bit of noise but hardly perceptable at idle. And a carb slide rattle you'd hear at idle - believe me, you would!

[Reinhoud]

21 hours ago, Gixer1460 said:

Er ! Primary shouldn't rattle - ever!

They do make a bit of noise but hardly perceptable at idle. And a carb slide rattle you'd hear at idle - believe me, you would!

The whole idea to use the angled teeth is to reduse noise.. 

 

The GS/GSX straight cut gears rattle!

[Gixer1460]

If a gear is 'rattling', its loose on its mounts / fixings - thus the tooth mesh isn't constant and will move back & forth, under and off load. When correctly meshed with minimal backlash any noise is imperceptible! I've had both straight cut and helical cut primaries in bikes, neither of which i'd say was loud / noisy! Now a straight cut gear set in something like a classic Mini Cooper gearbox - that is loud, noisy and whines 'like a bastard' basically due to the extra lash required for racing gear changes!