Reduction gearboxes in the Hub

Transmissions, Transfer Boxes, Axles, Drive Shafts
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Peter Connan
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Re: Reduction gearboxes in the Hub

Post by Peter Connan »

I very much doubt the side-effects will be as bad as Clem and Christo seem to be expecting, but I must admit to not having any experience of these particular axles.

However, since the increase in height (and therefore centre of gravity) is only about 75% of the increase in track width, stability should actually be improved.

Where you will take a knock is in the effects of irregular bumps on steering/directional stability. Therefore probably also an increase in the likelyhood of death wobble and similar effects, in essence making sure everything is tught and balanced will be more important.

However, during my national service I had several occasions to drive various Samil 20's, a vehicle with portal axles and much more chance of things going wrong ITO stability (much larger and heavier wheels and a very short wheelbase as compared to the track width and wheel size),and apart from one example that suffered from a steering wobble, the others were all quite happy at speeds in excess of 100km/h when one could find a steep enough downhill.

As for the reduction in power, I doubt it will be as much as 10%. A 4.8 with portal axles should still outrun a 4.5 comfortably?
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Re: Reduction gearboxes in the Hub

Post by Alex Roux »

Peter Connan wrote:However, since the increase in height (and therefore centre of gravity) is only about 75% of the increase in track width, stability should actually be improved.
I recall in October last year when we went to Rust de Winter, I had about 5cm to spare on each side as I drove through Lover's Lane. So width might be an issue.
Then again, if you look at some trials, such as Sandwani, the cars with different track widths do better as the main track is cut deep into the sand.
I also have not seen much on this on the Aussie forum. So this may either be too new, or due to price or some other reason it is not that popular.
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Re: Reduction gearboxes in the Hub

Post by martyn »

Hi guys. have a look at http://www.killeraxles.com its a European company (as in from Euros) German I think
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