Syncro 4&4 Discussion and Q&A last answered over 2 years ago.
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Is it possible to mount the Spare on the front of a syncro?
Have to move it from the inside as it now the sleeping area, I dont want to mount it under the skid pan and I dont want a swing away as I will be using a bike rack....
Im running out of ideas!!!
Thanks
Syncro (belong to Prof Mick Aston & Prof Alice Roberts)
Single Cab "Panzerakete"
Very risky using a different sized wheel and tyre (spacesaver), unless you have a decoupler.. the 4wd system doesnt like missmatched tyres.. very sensitive to even small rolling radius differences
Actually not as bad as you think. The overall diameter is close to the standard size (651mm) at 667mm. The 125/70/17 would be too small. Having one wheel slightly bigger or smaller than the other three will have no effect on the 4wd system at all. Think about it, thats why we have differentials.
syncropaddy wrote:Actually not as bad as you think. The overall diameter is close to the standard size (651mm) at 667mm. The 125/70/17 would be too small. Having one wheel slightly bigger or smaller than the other three will have no effect on the 4wd system at all. Think about it, thats why we have differentials.
See i'm actually a genius just a shame my cutting edge idea was doubted
The space saver would get you out of the poo and funnily enough save space and weight, could be a fivers worth of diesel over a year, think about that £20 in 4 years
I'm in my own lill world but its ok cos everyone here knows me !
I had wheel mounted on front of mine up till a couple of years ago till I got a rear swing out carrier. Didn't seem to compromise the cooling system.
Used a fabricated carrier bolted to the front cross member above the lower rad grill. Still got it if you want it?
I would think not compromise petrol cooling by 'ANY' slight reduction for TD diesels, maybe unwise...
Andrew, I think a different TRC size would have an effect of half the difference because of the differential, would it really be negated 100% by the cross-axle diff? No... surely not?
In this case the difference is 16mm in diameter, which, when you think about it is 8mm tread depth so we are looking at the difference between a new tyre and a bald tyre. Surely the drive train has to be able to take that difference up otherwise VW would have had to fit 2 spare wheels and insist on regular rotation. The drive train can easily take up that small difference as it can with the difference in diameters when tyre pressures are too high/low on the same axle.
Certainly if there was a 50mm difference in diameter then yes, there would be transmission issues which is why I said that the 125/70/17 wheel would not be suitable
But back to the post topic.... I wouldn't put a spare wheel on the front
Tyre rotation applies to EVERY vehicle and not just Syncros.
If you rotated your tyres like the book says - front to back and visa versa - and wore them down to the legal limit, all tyres should be the same diameter except the spare which is not in the rotation equation. What happens if you get a puncture? You fit the spare wheel which if unused, is a good 12mm larger in diameter so the transmission HAS to be able to cope with the increased diameter of the single tyre. This is done by the differential and a % slip in the VC.
The handbook speaks of a 'noticeable difference' between front and rear rolling circumference but does not quote a figure, nor does the official VW Workshop manual so where the 2mm difference and 3mm difference figures come from I dont know. Interestingly, the handbook speaks of replacing tyres in twos and not singly so by doing that there has to be an allowance for tyres of different diameters