| | Prokarts use the same front tyre and I have had the same experience.  Despite the additional weight of Honda senior after 2 heats (albeit in the wet) I could hardly keep the kart on the track despite having the benefit of an additional 6 degrees of castor.  Looking at the tyre now you can still see the release spots on every block of rubber.  I can't see any mould number but they are the purple spot ones. 
 The rears, by contrast, simply had too great a grip differential by comparison.  Initially I though this was simply set up, however, a shore gauge demonstrated the significant hardness difference and using an older set of fronts with these rears transformed the kart.
 
 How can you tell the W5 v W6 from the tyre and where is the mould number stamped?
 
 Graeme
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