19 replies to this topic

[MRA]

The noise you hear when you are actually driving the car is oil shear, or another way the trapped oil is being diverted at such a high speed it breaks the speed of sound, hence also why you also need to change your oil more frequently and the oil runs hotter with SC gears.

Not that JKD did a particularly good job of cutting gears, that shows up in the wear on the teeth flanks, and is down to design and materials, the teeth having to "roll and slide" doesn't help either.

As for rollers..... if you have high levels of torque then you might want to spend safely on a set, I currently run both one set in a 1380 turbo and my own set of A+ type drops in a 1330 SPI Cooper, without issues, however I wouldn't run a "standard" style set in my turbo as the bearings last a few months...

If you run big sticky tyres and an LSD or ATB diff then again spend on the rollers as they are a lot less prone to failure.

Tran-ex gears used to be one of the best, however as they are no longer made and JKD have gone out of business the choices are limited for the roller type.

[rick.spi]

im hopefully saving for a sc box and sc drops, i decided if its too loud then ill fix it by getting a slightly better sterio

[Calver ST]

MRA - the Trannex (Dave Hirons) designed gears are still available - from Mini SparesCentre. Strong ties between Dave Hirons and Mini Spares owner Keith Dodd and his support of Hirons and his A-series equipment meant that when Hirons closed the original Trannex doors years back now, he transferred all production rights to his designs for the A-series stuff to Keith Dodd at MSC. The company MSC uses to produce said componentry were also involved with producing these parts for Hirons/Trannex originally. KC

[MRA]

MRA - the Trannex (Dave Hirons) designed gears are still available - from Mini SparesCentre. Strong ties between Dave Hirons and Mini Spares owner Keith Dodd and his support of Hirons and his A-series equipment meant that when Hirons closed the original Trannex doors years back now, he transferred all production rights to his designs for the A-series stuff to Keith Dodd at MSC. The company MSC uses to produce said componentry were also involved with producing these parts for Hirons/Trannex originally. KC

I like your use of the word involved

I stand by what I said Tran-X do not make these gears anymore.

Are they made from the same steel ?
What about the same processes ?
The same surface finish ?
Or the same heat treatment ?

The same name doesn't mean it's the same product..

[1963MKI]

The issue over noisy drop gears stems from the prolifically available Jack Knight stuff from years ago. JK used to make their gears fast and cheap so they were machined very poorly. The teeth looked like they had been cut with a saw blade rather than a tooth-cutting machine. Not reflected in their sale price of course- being the only real player in the ganme they made fortunes from badly made parts. They also machined in excessive back lash to make sure the gears fitted ALL applications, no matter howm badly bodged. This just made the noise thing worxe.
The MSC/EVO (original and genuine Trannex desugn) drop gears are manufactured using more exacting tolerances and far, far better quality with far les back lash. The result are gears that are MUCH quieter than previously available parts. PLUS they offer somethinmg ike 9 different ratios using a common idler gear. Where JK could only offer a limited 2 ratios with the same idler and drop gear, MSC can offer a minium of 3.

 

you mentioned the value of the jack knight sets ? any idea of the cost people are willing to pay for a good condition 1.08 set ? i have a set I got with a job lot of parts and I was going to hold on to them, but now considering selling them and using the money for other bits for myself that I know i'll use.