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Straight Cut Drop Gears


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#1 kappa

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Posted 13 October 2011 - 09:51 PM

How hard is it to fit straight cut drop gears to a standard 1275cc gearbox, what's involved and what exactly do i need for the conversion?

Any help appriciated

#2 jaydee

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Posted 13 October 2011 - 09:59 PM

Do you mean the transfer gears?

#3 Tupers

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Posted 13 October 2011 - 10:09 PM

Do you mean the transfer gears?


I'd imagine he does, I've always known them as drop gears.

If the engine's still in the car it's at least a days work for a novice as you need to pull the engine, remove the clutch and transfer case to get at the gears. If the engine is out of the car then an afternoon could see it done.

#4 jaydee

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Posted 13 October 2011 - 10:13 PM

I ask because hes talking about the gearbox, and drop gears are not in the gearbox..

#5 kappa

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Posted 13 October 2011 - 10:17 PM

I am assuming they are drop gears the sccr kit, if this helps

#6 kappa

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Posted 13 October 2011 - 10:23 PM

oh yeah the engine is out of the car already and the gearbox is separated from the engine as well and i was thinking bout fitting the sccr drop gears, if they are the right one, not to sure???

#7 Tupers

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Posted 13 October 2011 - 10:30 PM

Basically no.

Drop/transfer gears are the 3 that go from the crank to the gearbox, a SCCR kit is what's actually fitting inside the box.

Drop/transfer gears

Straight cut close ration gears

#8 kappa

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Posted 13 October 2011 - 10:46 PM

so what's the difference between these two and which ones do i need?

#9 Cooperman

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Posted 13 October 2011 - 10:49 PM

Why would you want straight-cut transfer gears with a standard gearbox? They are normally fitted to cars with the straight-cut close ratio (SCCR) gearbox on high power Minis to strengthen the drive train or to change the transfer gear ratio itself.
The big disadvantage is they are so noisy that it becomes very unpleasant on any journey of more than a few miles. In fact my 'S' has them plus the SCCR box and I wear earplugs on road journeys of more than about 5 miles. In fact I wish I had kept with helical transfer gears and just had the SCCR gears in the gearbox.

#10 zebidee

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Posted 14 October 2011 - 02:53 AM

Why would you want straight-cut transfer gears with a standard gearbox? They are normally fitted to cars with the straight-cut close ratio (SCCR) gearbox on high power Minis to strengthen the drive train or to change the transfer gear ratio itself.
The big disadvantage is they are so noisy that it becomes very unpleasant on any journey of more than a few miles. In fact my 'S' has them plus the SCCR box and I wear earplugs on road journeys of more than about 5 miles. In fact I wish I had kept with helical transfer gears and just had the SCCR gears in the gearbox.


I've heard before that the straight-cut drop gears are far louder than SCCR gears, would helical drop gears with an SCCR gearbox be bareable for longer journeys??

#11 Ivor Badger

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Posted 14 October 2011 - 11:15 AM

so what's the difference between these two and which ones do i need?


What you will need is ear defenders to go anywhere.

#12 Cooperman

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Posted 14 October 2011 - 12:49 PM

Why would you want straight-cut transfer gears with a standard gearbox? They are normally fitted to cars with the straight-cut close ratio (SCCR) gearbox on high power Minis to strengthen the drive train or to change the transfer gear ratio itself.
The big disadvantage is they are so noisy that it becomes very unpleasant on any journey of more than a few miles. In fact my 'S' has them plus the SCCR box and I wear earplugs on road journeys of more than about 5 miles. In fact I wish I had kept with helical transfer gears and just had the SCCR gears in the gearbox.


I've heard before that the straight-cut drop gears are far louder than SCCR gears, would helical drop gears with an SCCR gearbox be bareable for longer journeys??


I always used SC CR gears with helical transfer gears and thought them quite acceptable. Then I damaged the transfer gears on a rally and decided to fit the SC transfers. I really wish I hadn't as they really are noisy. It's OK when wearing crash helmets and I suppose as the SC transfer gears are meant to be used in competition where helmets are used, but on the road sections of rallies or just road driving they are very tiring and unpleasant for the ears. I don't think SC transfer gears are really necessary until the max power exceeds about 120 bhp and that's a race-spec engine.
Now, a SC CR gear set is a different matter and does make the car super to drive if it's modified to around 90+bhp, although 1st gear is then rather high and a lower final drive ratio is usually considered necessary in order to pull away cleanly without too much clutch slipping. The lower final drive means more revs for a given cruising speed.

#13 ace01

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Posted 14 October 2011 - 01:21 PM


I've heard before that the straight-cut drop gears are far louder than SCCR gears, would helical drop gears with an SCCR gearbox be bareable for longer journeys??


That's a better combination as straight cut gears only make a noise in 1st, 2nd and 3rd, unless of course you have splahed out on a straight cut diff.

#14 AndyMiniMad.

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Posted 14 October 2011 - 02:46 PM

Why do you want tio fit Straight cut gears, Or drop gears to a standard 1275 engine.....I assume its because you WANT the noise they produce...Which is fair enough, each to their own and all that...But as has already been mentioned, they are megga noisy. I have the straight cut drops due to necessity...and went on the Thistle run this year, which is a 300mile round trip for me.....Never even noticed the noise when pushing the car through the Glen Orchy stage.....But wanted to kill myself after 50 miles on the A9 south...they really are that bad..


Edit...When I say pushing the car I dont acctually mean PUSHING...lol.

Edited by AndyMiniMad., 14 October 2011 - 02:48 PM.


#15 Gulfclubby

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Posted 14 October 2011 - 02:54 PM

while it's not a Mini, this video is an amazing example of how bad a fully straight cut drivetrain sounds:) Or how great, depending on your taste and the thickness of the wax in your ears.




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