tranmission noise

[gavcos]

Hi all

I am after some advise,my wife and i have just returned from a day in one of caterham's hire cars,and what a day,the grin just got bigger as the day went on.

The caterham we had was 1.8 roadsport 6 speed,great fun.

There are two things that i am unsure of.

First thing there seemed at lot of transmission noise as if the gearbox was straight cut and second trying to travel at A road crusing speed seemed very frantic,Have to say the box was great to use.

Mentioned this to caterham on our return was told that the box was not straight cut but the noise was more likley the diff and the fact that there is no sound deadning,I appreciate that they will not be quiet like a road car but i think on a long journey it could become very tiring.They also mentioned that they now do a touring six speed box at a price which would help high speed crusing.

Is this level of noise normal,and how is long journeys with this box.

Any advise you could give would be very much appreciated.

 

Many thank

 

Gavin

 

 

 

 

[CageyH]

TADTS - They all do that sir.

On long journeys, people tend to wear ear plugs or MP3 players etc.

 

I recently drove from Bristol to Toulouse and yes, it was noisy, but only because I had the MP3 player turned up.

I have a semi-helical 5 speed box, which is better for touring, as it has a lower top gear.

You will get used to the clonks from the diff etc.

[CageyH]

Oh, and welcome to the mad house!

[Frying Pan]

Caterhams are not quiet cars Hope you enjoyed your time today 😬

 

The diff is very noisy - they all make a variety of horrible clanks, groans and whines, which are all perfectly normal. Don't forget the diff was designed to be rubber mounted under the boot of a Sierra, miles away from the passengers beneath layers of sound deadening. On a Seven, it it bolted directly to the chassis a foot from your ears

 

Gearboxes are pretty quiet, although they do grumble a bit in neutral.

 

I built a 1.8K with 6-speed, and I love the frenetic noise and the amount of gear changes.

 

On long motorway runs, I do tend to wear earplugs, but this is more due to the wind rushing past than the transmission noise...

 

I believe the 'touring' six speed is actually a different diff ratio, but I could be wrong.

 

Guy

 

 

 

See some pictures of the build here. 10000 miles completed!

[gavcos]

Thanks

Having always had hot hatches it did seem noisy,but it was fantastic fun,

[rgrigsby]

Hi Gavin,

 

In general a seven is quite a bit noiser than most cars, it's a combination of gearbox, diff and engine noise and the way they are mounted. In terms of cruising speed/revs that depends on the gearbox and diff ratios. The 6 speed box has a 1:1 top gear so in effect it's similar to 4th in a 5 speed box. There is no overdrive, I could be wrong but I didn't think there were alternative ratios available, I suspect the "touring box" is actually a different diff ratio to give longer overall gears.

 

It's probably a bit late now to find out but I suspect the hire car will have had a 3.92 diff with the 6 speed box which is about as short as it gets and therefore as noisy and frentic as well. I common combination is the 3.62 diff with the 6 speed box which gives a slightly longer set of gears but you still get decent in gear acceleration. What you go for does to a certain extent depend on the engine choice as well.

 

As for other noises, yes they do clunk and bang a bit and there are quite often general whining noises from the diff, as the sales person said this is pretty much down to the lack of sound deadening and also the proximity of everything ie you are almost sitting on top of the diff!

 

You will get used to it and many people on this forum have covered 10's of 1000's of miles in their cars without any problems.

 

A common addition is some sort of intercom system with ear defenders, these can be used to reduce the noise levels, ease conversation and you can also plug in things like an MP3 player, mobile phone, sat nav or even a PMR car-car radio. (or all of the above if you a gadget person 😬)

 

I personally have an aeroscreened car with an Autocom intercom with MP3, mobile phone and PMR radio inputs and whilst it's not everyone's cup of tea I've been across europe and the US in it without any problems.

 

Depending on were you are I'd recommend you get down to your local seven meet (either L7 Club or W**tfield or even a Se7ens list meet if you there is one nearby) as I'm sure lots of people can give advice and you would have a chance to try other cars for size/noise as well.

 

If you really want to be terrified pop over the Dartford bridge and come for a ride in my Duratec 😬

 

 

Rob G

www.SpeedySeven.com

 

 

Edited by - rgrigsby on 3 Aug 2006 21:42:03

[gavcos]

Thanks Rob

I don't make a very good passenger,I really like the idea of an R300 and then possibley change the gearing to give me the best of both worlds.

 

Gavin

[rgrigsby]

Sounds like a good choice, I'm sure someone one here can confirm whether different ratios available for a 6 speed, otherwise it's a fairly simple matter to get the diff ratio changed and you're not a million miles rom somewhere that can do it.

 

Rob G

www.SpeedySeven.com

[shn7]

Being one of those who has a seven with a straight cut box I can tel you it is VERY LOUD. If I cruise at 70mph for more than a couple of minutes without ear plugs my ears are ringing. So I think the car you hired will not have had a SC box. It is a case of TADTS as already stated. To a degree you get used to it and you also take action to prevent it being harmful by wearing earplug or using an intercomm to communicate with your passenger.

 

Just get on and buy one 😬 . You won't regret it I'm sure.

 

Steve.

Not forgetting Percy the Polar Bear

[7 wonders of the world]

I'm with Steve, I run a Tran X straight cut and aside from 4th which is direct, it's 'musical' which in a way adds to the charm of the 7 mine also has a short 5th so things do get a little noisey @ 70 plus.......... 😳 - perfect ratios and superb sift though

 

so there are a number of options here:

 

1- Wear ear plugs

2- Take the doors off so the wind noise drowns the gearbox noise 😳

2- Press the 'little' pedal even more and the TB's dorwn evrything out

 

I understod that the CC 6 speeder was straight cut 🤔, the one we trst drove was certasinly bl00dy noisey if not ❗

[shn7]

7 wonders,

 

I think you're mistaken re the CC 6sp. The one I had in a previous 7 was silent by comparison with my current SC box.

 

Steve.

Not forgetting Percy the Polar Bear

[7 wonders of the world]

Steve,

 

Definealty a 6 speeder with only 8k on the clock, OK ao not as noisey as my SCCR box but a lot noisey than a previous helical 5 speeder I drove

 

 

Who needs 6 gears anyway

[shn7]

 

Steve.

Not forgetting Percy the Polar Bear

[Bozz]

Gavin

 

Just to add my half penny worth.

 

I run a 1.6K SS with 6 speed box and short 3.92 (not LSD) diff.

 

It's not the ideal combination for motorway work (4000+rpm at 70mph) but it is a great combination everywhere else 😬.

 

The diff does whine and clonk and the gearbox whine a bit in 4th but it's all part of the charm IMHO.

 

Bozz

 

 

 

My Chocolate Orange here

[Mrs Kipper]

I have the same combination as Bozz. The gearbox rattles a lot when the engine's idling and you declutch, to the point where you think that something must be loose in there. But the most noise is on overrun in 4th and I think most 6 speed owners will confirm this.

 

 

 

Kipper

 

Fun is not a straight line.

[Tom_C]

Mine's an ex-academy race car, so has the 5-speed box but no carpets etc to deaden the noise. The diff is very loud around town and up to around 50mph, but once in 4th or 5th at speed really all I hear is the wind noise and exhaust.

 

Cheers

 

Tom

 

FH54WLX - only the car supports ManU, honest!

 

see here - UPDATED

[gavcos]

Thanks guys a great help

[Paul Formston]

Hi Gavin the first seven I ever went in was Malcom Kitteridges,(MAL) and that was the first thing that struck me what a noisey Diff, and I mentioned it at the time so when he took it for a sevice at Caterham he mentioned to caterham, they said that it was Normal, any way I got my Caterham on the road and I got my diff from elsewear and it was a lot Quiter, so again he mentioned it to caterham and they went for a run in the car and said that it was normal. Any way he decided to take the Diff out and have it overhauled at BGH and they said the pinion bearings were over tightened so now it is Quit, 😬 so you don't have to put up with a noisey diff Regards Paul

[Colin Mill]

I guess I'm lucky but I think the gear noises on mine (which were most noticable on over-run) have settled down a lot now its got about 1500 miles on the clock - that or I'm going deaf. It seems to be quieter than the old series 3 Landrover I used to drive which may have been good training for owning a 7.