Blokarts have a narrow front tyre (12.5" x 2.25") with a trigonic cross section (ie small foot print when upright but increased when laid over), that is until 2008. The new blokarts have a round profile tyre as fitted to many prams and golf trolleys today. A bit like a racing slick.
My experience has been that I wear the tread off the sides of the trigonic front tyre long before I wear it off the middle of the tyre, also a front tyre usually outlasts two or three pair of rear tyres, especially when sailing on bitumen, concrete or gravel.
The blokart seems to benefit with a narrow front tyre giving better grip due to smaller footprint and therefore greater contact pressure per unit of contact area.
Whether this configuration of wide rear tyres and narrow front tyre gives optimal steering for a class 5 yacht or other, is for somebody else to say as blokart is my only land yacht experience to date.
An available blokart accessory is the "big fork" which allows the fitment of the same size wheel as the rear wheel to the front of the blokart. This configuration was used by Mr. Blokart himself (Paul Beckett) in the performance class at last year's nationals on the beach at Yeppoon.
On varying surfaces this may prevent "burying" of the front wheel in softer patches and therefore maintain speed but at the sacrifice of grip in turns if using a ribbed tread on the front.
My suggestion (for a blokart at least) is for the same sized rims all round with the widest ribbed tyre on the rear with the narrowest block tread tyre on the front.
Does that sound logical??? Cheers Cisco.
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