Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

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slowpoke
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Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

Postby slowpoke » Sun Feb 08, 2009 2:26 pm

The (supposed) longer life of brass over poly/plastic seems to me to be the sole advantage..
With the brass bush now installed and with the car in motion, the gear lever 'action' feels NO DIFFERENT to how it did when the g'lever was fitted with Mazda's poly/plastic bush (Sheet Spring).
With the car stationary and the engine not running and the g'box in neutral there is now a distinctive 'metallic'/'agricultural' sound when the g'lever is moved through the various gears. This sound wasn't noticeable when Mazda's plastic/poly bush was fitted.
Is this slight, but noticeable, sound normal ?
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Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

Postby Fuzzlet » Sun Feb 08, 2009 10:32 pm

Mine still has the OEM bush and makes a very metallic sound...
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Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

Postby 93_Clubman » Mon Feb 09, 2009 6:33 pm

SP, I think that sound will be the soft metal to hard metal contact as a result of the new bush. I also think this is one of those mods that really makes a difference to owners whose vehicle's gear change feel is not quite right. I suspect, but could be wrong, that NA6 owners would feel little advantage from the brass bush in a reasonable mileage NA6 given their great gear change (& free revving motor).

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Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

Postby Locutus » Mon Feb 09, 2009 8:25 pm

mine didn't make much of a difference, but the shift felt more metallic (more direct feedback) and required slightly less effort. i've got an IL shortshifter through, and changed my turret oil at the same time.

i expected more of a difference but i'm not really fussed since it was such a cheap mod.

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Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

Postby grump » Tue Feb 10, 2009 7:14 pm

I'm just a little bit confused, A short shifter, what is it?, A gear lever that is shorter than the standard. don't spend any money, just cut it shorter. And at the end of the day you can have the same effect just grabbing the lever lower down. Call me stupid, or perhaps a little bit argumentitive, but its the last mod I would bother to do.
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Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

Postby sliq » Tue Feb 10, 2009 7:50 pm

grump wrote: And at the end of the day you can have the same effect just grabbing the lever lower down.


that's the problem, it takes effort to grab the lever lower down.
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Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

Postby rossint » Tue Feb 10, 2009 7:57 pm

I'm pretty sure that they also have a shorter throw than standard, so the distance between the gears is reduced by changing the pivit point of the lever.

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Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

Postby Fatty » Tue Feb 10, 2009 8:02 pm

yes, the short shifter kit actually raises the fulcrum / pivot point (the ball) at the base of the shifter. so its a bit more involved than just cutting the lever. as sliq said, just cutting the lever would result in a lot more effort being required to shift gears.

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Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

Postby grump » Tue Feb 10, 2009 8:26 pm

The pivot point. ( Ball ) is a fixed point in the gear shift, therefore the only way you can make the gearshift shorter is to cut it down, if you know what i mean. When you buy a short shifter , you only get a gear lever. Nothing else. think about it!!!
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Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

Postby Fatty » Tue Feb 10, 2009 8:37 pm

iirc, they supply a large spacer that fits below the ball, thus raising the pivot point.

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Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

Postby grump » Tue Feb 10, 2009 8:40 pm

O.K Fatty ,you got me, didn't realise that they supplied something that raised the pivot point
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Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

Postby RobH » Thu Feb 19, 2009 2:54 pm

I have one of the IL Motorsport quick shifters for the 6 speed. Has anyone had issues with the original bushing from Mazda not fitting snugly over the end of the shifter? Mine appears to be very loose and therefore rattles. Where is it possible to get a new bushing from (possibly Beatrush brass one)?
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Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

Postby Benny » Thu Feb 19, 2009 5:04 pm

If your plastic bush is in good condition, and is not worn, putting in a brass bush in won't make any difference to the feel of the gearchange.
If your plastic bush is worn however, then putting in the brass bush will bring it back to the way it should be.
The advantage of having a brass bush is that it will last a lot longer and wear more slowly than the plastic bush.

As far a short shifters are concerned, they do alter the fulcrum point of the ball and this gives you MUCH shorter throws between the gears.
However, for the short shifter to work well, the fit of the bush is very important, and the diameter of the shift lever can be a bit different to the OEM shifter, so the fitting of the bush is very important.
That's why many of the better short shifters also come with a plastic bush which is supposed to fit the short shifter perfectly, although my IL one was a bit too big for the bush they supplied, so the bush had to be reamed out a little to make a perfect fit.
The fit of the bush to the shifter is very important to the shift feel, and how stiff it is.
If the bush is to tight, the shift will be stiff and difficult, too loose and it will swim and feel very sloppy.

If you put in a short shifter, and you play with the bush to get the fit right, and the shift still feels a bit tight, this is quite OK.
After a few thousand k's, it will loosen up and feel like a hot knife through butter.
I know mine was a little stiff at first, but it quickly settled down and I can now change gears easily with just one finger.
The short shifters really do make a difference.
After using one for a while, when you get into a standard 5, the gearshift will feel like rowing a boat!
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Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

Postby Locutus » Fri Feb 20, 2009 9:56 am

my 5 speed IL shifter was installed by the last owner, but the plastic bush i replaced fit the end of the shifter quite snugly.

agree with benny's comments above - IL claims 40% reduction in throw, and i believe them. i actually hated the shifter when i first bought the car because i felt the throws were too short. i grew to love it after a few weeks, and now driving a 5 with the standard shifter feels like shifting in a camry.

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Beatrush Brass Bush versus Mazda's Poly/Plastic Bush

Postby 93_Clubman » Sun Feb 22, 2009 12:46 am

RobH wrote:Where is it possible to get a new bushing from (possibly Beatrush brass one)?


Rob, if you need to follow-up on the above try PMing 'drifter' or ' SPy vs. SPy' who took part in the last group buy - they might have a bush for 6 speed FS from the look of their last post in the brass bush GB thread.


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