A slightly longer outer cable will push the brakes up while they're not being applied. However they may still touch the tyres during braking if they would have been the right size to begin with.
Luckily yours seem slightly too short (you can see the result in the way the cable points downwards between the V-brake arms), so it would all work out. I reckon 5-10mm extra would do the trick.
Removing the rubber cover will also solve the problem, but you'll need to pay more attention to cable lubrication then.
I'd advise against using washers, as they'll alter the leverage and the balance of the brakes. Sure, you can adjust the screws near the bottom to compensate, but the braking feel will never be the same. Shame really, as these Tektro brakes really are excellent.
Thanks for the advice.
did a bit more research on the brake arm length.
Tektro arm length is 102mm, where as the Shimano Acera/Deore brake arm length is 107mm so that may help as well. Ill resolve that outer cable length this evening.
Yes I know the tyres are probably too big for the bike, but the ride quality is sublime...the track i go to is rocky and compacted and my previous Schwalbe CX Comp Semi Slicks where a bit to skittish and lacked grip...
these tyres from the short period make the bike feel so smooth and secure I have to make this work
even if its only for a few months until I can buy a "proper Bike" either an Voodoo Bantu or preferably a Voodoo Hoodoo.