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Physically Smallest Diff
scootz - 5/2/13 at 01:51 PM

I'm fannying about with a V-twin engine just now and would like to couple the drive-flange directly to a differential.

My space is restricted, so I'm looking for a diff that's particularly short in length.

Does anyone have any suggestions, or can offer any length dimensions of certain units?

Ta muchly!


mcerd1 - 5/2/13 at 02:18 PM

I'm sure there are smaller ones, but you welcome to borrow/measure up one of my sierra diffs (7" )

[Edited on 5/2/2013 by mcerd1]


nick205 - 5/2/13 at 02:45 PM

Quad bike diff perhaps, no idea of cost/strength/ratios etc, but they must be pretty compact.

Failing that what about a Honda CRV or something similar.


40inches - 5/2/13 at 02:57 PM

Front diff from a Sierra 4x4?


MK9R - 5/2/13 at 03:41 PM

The free lander is shorter than a Sierra


adithorp - 5/2/13 at 04:01 PM

I had a look into connecting engine direct to diff a while ago. The problem is the two have to be perfectly aligned. Any mis-alignment or flex between the two can result in failure of one or both.


bashracing - 5/2/13 at 04:56 PM

1.6 mx5 6'' diff is fairly short


me! - 5/2/13 at 05:01 PM

The Fiat Panda 4x4 uses a pretty small rear diff- but good luck finding one!

Maybe some of the other very small 4x4's would be some use, Subaru Justy, Diahatsu Charade etc?


scootz - 5/2/13 at 05:07 PM

Cheers guys. Will look into some of the suggestions.


scootz - 5/2/13 at 05:08 PM

quote:
Originally posted by adithorp
I had a look into connecting engine direct to diff a while ago. The problem is the two have to be perfectly aligned. Any mis-alignment or flex between the two can result in failure of one or both.


Maybe put a single UJ between them?


bashracing - 5/2/13 at 05:18 PM

or try these lot for a small rubber doughnut coupler
http://www.fptgroup.com/distfinder/dist_results_uk.asp


scootz - 5/2/13 at 05:29 PM

Ooh... the Honda quad diffs are very neat, but I guess they wouldn't like 80ft/lbs, 10k rpm limit and 600kg vehicle weight!



scootz - 5/2/13 at 05:29 PM

quote:
Originally posted by bashracing
or try these lot for a small rubber doughnut coupler
http://www.fptgroup.com/distfinder/dist_results_uk.asp


Cheers... will look into it.


matt_gsxr - 5/2/13 at 06:20 PM

What about one of these beauties?
http://www.transworks.biz/minidiff.html


big_wasa - 5/2/13 at 06:44 PM

the mondeo/jag 4x4 maybeworth a look.



bashracing - 5/2/13 at 06:56 PM

quote:
Originally posted by matt_gsxr
What about one of these beauties?
http://www.transworks.biz/minidiff.html

hoooooooowwwwww muuuuuuuuuuuuuuuuuuucccccchhhhhhhhhh???????????????


JC - 5/2/13 at 06:56 PM

Might be a hens teeth suggestion, but Suzuki Cappucino? It's gotta be small!

ETA at least 2 on the 'bay



Suzuki Cappuccino Rear Diff Differential 660cc 1994 Warranty | eBay

[Edited on 5/2/13 by JC]


scootz - 5/2/13 at 07:04 PM

quote:
Originally posted by bashracing
quote:
Originally posted by matt_gsxr
What about one of these beauties?
http://www.transworks.biz/minidiff.html

hoooooooowwwwww muuuuuuuuuuuuuuuuuuucccccchhhhhhhhhh???????????????


£1200???

That's pretty cheap considering it's your diff, has a reverse and also the brake calipers / discs.

An reverse diff from Elite is almost twice the price!


scootz - 5/2/13 at 07:06 PM

quote:
Originally posted by JC
Might be a hens teeth suggestion, but Suzuki Cappucino? It's gotta be small!


Found one!

Suzuki Cappuccino Rear Diff Differential 660cc 1994 Warranty | eBay


scootz - 5/2/13 at 07:08 PM

Ah... just spied the brake kit is an extra $650.


scootz - 5/2/13 at 07:31 PM

quote:
Originally posted by big_wasa
the mondeo/jag 4x4 maybeworth a look.







Yup... that's quite squat. I wonder if the input shaft could be shortened a bit?


Andy S - 5/2/13 at 08:19 PM

Triumph Spifire


minitici - 5/2/13 at 08:43 PM

quote:
Originally posted by scootz
I'm fannying about with a V-twin engine just now and would like to couple the drive-flange directly to a differential.

My space is restricted, so I'm looking for a diff that's particularly short in length.

Does anyone have any suggestions, or can offer any length dimensions of certain units?

Ta muchly!



Scott, Which end of the vehicle are you fitting the differential?

Is it for the front of a reverse trike?

Or are you trying to drive a single rear wheel of a reverse trike?

As others have said a Freelander rear differential is fairly compact and has a light alloy case.


scootz - 5/2/13 at 09:14 PM

Hi Doug,

It's for a Smart Roadster with an Aprilia V-twin mounted transversely.

PS - I've been looking at some of the bigger ATV's (400+kg's) and it seems that plenty of them have LSD's and a fair bit of torque. The likes of this Can-Am diff has Visco-Lok...

2013 Outlander 1000 XMR Front Differential Diff Assembly Canam Can Am 705401077 | eBay


minitici - 6/2/13 at 11:43 AM

Scott,

You could always fit a sprocket to the input flange of a differential and link to the engine via a short chain.


scootz - 6/2/13 at 06:58 PM

Hadn't thought of that. Is there a chain-length below which you start running into overheating issues?