Layshaft noise

[Paul Holywood]

My R500 has a rattle on tick over from layshaft it seems, depress the clutch and noise has gone, is this common and should I get it seen to or just accept it?

If it's something that requires repair how much should I expect to pay to have the sorted?

[F355GTS]

TADTS

[Eccles52]

My Sigma 150 has the same thing, it's been like it from new (2007) and has done 15K without getting any worse so I would think it's fine although mine is a much lesser machine

Admittedly it's still bloody annoying and I'd like to fix it

[IBDAET]

THe noise is actually the clutch release bearing, not the gearbox. As Mark says this is common, and not really an issue. It will get really noisy before it fails, then I'd replace the whole clutch.

[Paul Holywood]

IBDAET said:

THe noise is actually the clutch release bearing, not the gearbox. As Mark says this is common, and not really an issue. It will get really noisy before it fails, then I'd replace the whole clutch.

That's a relief I was under the impression its the gearbox ,thanks for your help.

[Paul Holywood]

Eccles52 said:

My Sigma 150 has the same thing, it's been like it from new (2007) and has done 15K without getting any worse so I would think it's fine although mine is a much lesser machine

Admittedly it's still bloody annoying and I'd like to fix it

Interestingly , does yours sound like the engine is knocking until you depress the clutch ? Or have you a different noise.

[Eccles52]

Ahh, hah, perhaps I have a different noise then. Mine is a rattly rumble which slows and disappears when you put your foot on the clutch - you can hear the input/driven shaft slow down in the box.

Not sure if heavy duty bearings would cause this but can't imagine Caterham would fit them as standard.

[Paul Holywood]

Mine does go when you depress the clutch, but sounds "clackity clack" .
lol it's very hard to discribed what I can hear.

[downsman]

Lack of sound deadening means we notice all sorts of noises that can't be heard in a normal car.
Earplugs make my car sound much more refined

[Shropcat]

As above, TADT. Made worse by the ultralightweight flywheel.

[Paul Holywood]

Apologies, I didn't know what the abbreviation (tadts) meant, and when I see it a second time had to use google.
Thanks, so it's down to lightened flywheel and clutch?
Forgive me for my stupidity but I can't see the connection.

[IBDAET]

Flyuwhjeel has nothing to do with it. It is 90% CRB, or if the car has had its neck wrung and uses a sprung clutch pressue plate it can be the springs in the clutch plate rattling where they have becoime loose.

On an R500K there is no organic plate that is really capable of handling the required torque capacity, so there is a slim chance its the plate.

[Paul Holywood]

IBDAET said:

Flyuwhjeel has nothing to do with it. It is 90% CRB, or if the car has had its neck wrung and uses a sprung clutch pressue plate it can be the springs in the clutch plate rattling where they have becoime loose.

On an R500K there is no organic plate that is really capable of handling the required torque capacity, so there is a slim chance its the plate.

Thanks, if what you say is correct and I decide at some point to replace the clutch ,given the high torque, is there a more substantial kit I should go for, or should I keep oem.

[Paul Holywood]

IBDAET said:

Flyuwhjeel has nothing to do with it. It is 90% CRB, or if the car has had its neck wrung and uses a sprung clutch pressue plate it can be the springs in the clutch plate rattling where they have becoime loose.

On an R500K there is no organic plate that is really capable of handling the required torque capacity, so there is a slim chance its the plate.

Thanks, if what you say is correct and I decide at some point to replace the clutch ,given the high torque, is there a more substantial kit I should go for, or should I keep oem.

[BertBert]

just ignore it. If something breaks fix it. But they all rattle, not worth worrying about.
Bert

[Paul Holywood]

Advice taken,thanks.

[MoPho]

When I searched about this some years ago this is what I found: "The first motion shaft and laygear are dancing around a bit due to the fact that they are effectively idling with alternating accelerative and deccelerative cycles in time with the engine"
Apparently Caterham has varied the tolerances over the years and some boxes do it and others don't

[IBDAET]

There are only two clutches suitable for road use, unless you want to get into race clutches which will only last a couple of thousand miles (been there, done that). Today I run a 260bhp K and have done 5k miles on a Helix organic clutch having wrecked the AP alternative sold by Caterham previously with a less powerful engine.

The weak point is the cover, not the drive plate. I have the Helis whihc has a drive plate rated at 130lb/ft and I'm putting around 180lb/ft through it with no issues of slippage.

[Paul Holywood]

MoPho said:

When I searched about this some years ago this is what I found: "The first motion shaft and laygear are dancing around a bit due to the fact that they are effectively idling with alternating accelerative and deccelerative cycles in time with the engine"
Apparently Caterham has varied the tolerances over the years and some boxes do it and others don't

I was under the impression it was this , I presume when depressing the clutch the shaft becomes motionless, thus no noise.

[IBDAET]

Then why does it also occur on type 9 boxes also?