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Hi guys,

Ive got a set of 205/50/R15 K61 V70A's which I got a few weeks ago. Had my first event today with them, a hillclimb. The track was VERY cold all day. Temp sat at around 10deg until about 2pm when it rose slightly. I was having huge issues getting the tyres to work. I've done some googling and have come up with some differences in the spec of the tyre within each compound. What I have found is that the softs are K11's/K21's, mediums are K60/K61 and the hard is just K90. I have read that they do wet weather tyres for each compound but I haven't read anything as to which one is the wet weather tyre. Mine have K61 marked on the sidewall. Can anyone shed any light on this?

Ash.

doubtful you were getting them hot enough if road temp was 10. a v70a is a wet/dry tyre. but if looking for a wet tyre, then W700 would be similar.

how long was the hillclimb in seconds from start to finish?

Its definitely a case of not getting temp into them. Also was running a fast street alignment with not much camber or and crappy toe setting. This wouldn't of helped either but will definitely get a proper alignment this weekend. The car was a dog to drive. Loads of understeer unless I got the car balanced juuuussstttt right. Not looking for a wet tyres, just after some confirmation as to weather there are wet/dry variations within the V70A range.

A run is in the mid 38's for me currently. 630m with an rise of 70m from start to finish.

Sorry I can't help you out with a wet weather V70a compound but why not contact your state Kumho Motorsport dealer and ask?

I’ve used the mediums for a number of years on the track and they take about a lap to warm up, so for a hillclimb they would be useless. The softs would be the ones to get.

I also found the wet weather capability of brand new V70a’s is way below your normal road tyres.

You really need a dedicated set of rims and wet tyres if the budget stretches for rainy days. To give you an example, a few years ago at a wet Wakefield, one of our members who normally runs mid pack, fitted a set of 6 year old wets and was the fastest car for a number of sessions. Probably 4 seconds faster than he should have been running. A lot of chest beating went on about that.

I didnt get the softs (could of got a set for $800!) because these tyres need to do both hill climbs and super sprints. I figured the softs would just overheat after a lap or two and I haven't seen anyone with a MX5 run softs.

Budget wont stretch for 1x set of dry semi's, 1x set of wet tyres, 1x set of road tyres. My plan is to run my R1R street tyres at the hill climb or when its wet. They're a very good tyre.