Straight cut gears or drop gears
Turbo Mini Forums

I'm just wondering what makes the noise is it the drop gears?

Or the straight cut gear set?

Apart from Robert anyone running straight cut gears with standard drop gears? What are the drop gears good for standard?

What are the ones to normally fail? The gears smashing up? Teeth breaking?

What is the noise like from normal?

Edited by NickG on 27th Jun, 2011.

Straight cut drops and normal straight cuts will both make the noise.

And its a whining noise, sounds like a bearings gone. Theres some awesome vids on youtube.

In boost we trust

SC box isn't all that loud I don't believe.

I reckon that the majority of the noise comes from the drops.

If something is worth doing, it's worth doing half of.

It the oil squirting out sideways at super sonic speed

No, Honestly, its the noise of the teeth on the gears clashing against each other at a high rate.

Helical gears still suffer from the same, but the noise is no where near as loud since the contact of the teeth is spread across more than one tooth, each contact point is small, and rather than a straight impact, the contact is more of a rolling motion.

Lol maybe over at Tmf or maybe As good as flushing the engine with a hose sprocket lol.

I assumed it's the drops that whine in straight cut form and the gear set is not so loud over STD? Helical?

I would say most of the noise is the drops. We had helical box and s/c drops in the van and it was loud. With the new s/c box and old s/c drops there's not much difference.

So any one running STD helical drops with straight cut gear set? Come forward:p

I will be.

If something is worth doing, it's worth doing half of.

Sc drops make the majority of the noise.

As for power, rovert used them at 200+bhp, when they did finally go I believe he replaced them with more helical drops.

I am using sc gears with helical drops, but I am unable to give a power limit for them

Audi s4 b5 - 470bhp & 486ft lbs

On 30th Apr, 2012 Brett said:
yeah stick the bit in and give it a wobble

How is the volume like Benny? Compared to STD or what you had before? Ps what did you have b4

the sc items shouldnt be too loud, just like driving in 1st gear all the time.

i am using the clubman gearset at the mo, but havnt actually used them yet.

Audi s4 b5 - 470bhp & 486ft lbs

On 30th Apr, 2012 Brett said:
yeah stick the bit in and give it a wobble

Ah, how long till you are up and running?

hoping to be in the next week or two.

Audi s4 b5 - 470bhp & 486ft lbs

On 30th Apr, 2012 Brett said:
yeah stick the bit in and give it a wobble

Am using the MS Clubman SCCR gear set and a Tran-X semi helical diff with standard (albeit new) helical drops. Have had them in since June 08 and done 2,300 miles up to 130 nannas and 125 curlies. Not so much as a sniff of a problem at these very mild powers.

And my box only whines in 1,2 & 3. Drop her into 4th and all the whine has completely gone. Makes cruising a bliss.

There is an article in Vizards 'How To Modify Your Mini' about topping and tailing the gears to reduce bottoming which when combined with the single contact pint of straight cuts can be a contributory factor. It is said to vastly reduce the whine from straight cuts.

And I share the opinion that it's the drops that are probably the highest source of whine. The fact that two of them don't run in a submerged oil bath can't help matters. The choice for my helical drops was noise and a chosen spec which was at a lowish power and torque. I know my drops will need changing to SC if I want another 50 brake, and tbh I can't be arsed with the racket.

Richard.

Minivanless, but reluctantly happy living with the decision. There'll be another one day.
http://www.youtube.com/profile?user=minimadmotorman#p/u

robert has put through helical drops and SC gearset 190 odd brake for years and many miles and trouble free!

its the third gear and head set which strips using standard box and helicals when you place some power through

the SC gearset and helical drops combination eliminates this and the noise