Kumho V720
#61
No real controlled testing but we did finally run our 225/45/15's on a dry track at ACS last weekend. Not many laps but they felt good. Hard to say anything meaningful about grip levels. They seemed to tolerate heat well. They steer nice, better than Rivals. Despite being narrow compared to the other 225's, they stopped really well and had good feedback both under braking and max slip angle cornering. No adverse wear observed. Again, not a thorough evaluation at all, just some small observations based on a session or two goofing around on track.
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#66
whp (200WHP)
rev limiter (7500)
5 or 6 spd (6SPD)
diff ratio (3.28)
diff type (Getrag) (Clutch type I think)
wheel width & offset (Your 15x8s)
shocks (Stock MSM Bilsteins)
spring rates (400F/350R)
sway bar diameters (Stock MSM)
alignment (I think -1.5 all the way around.)
Last edited by slmhofy; 02-24-2016 at 03:22 PM.
#67
SADFab Destructive Testing Engineer
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Location: Beaverton, USA
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Emilio, I'm going to assume you didn't experience anything similar to the delamination posted in the rx8 thread. And I know you probably didn't test them on the street. But any insight on longevity? Currently trying to decide between zII*s and these and the zII*s are known for their long lasting wear.
#68
Year chassis ('04 MSM)
whp (200WHP)
rev limiter (7500)
5 or 6 spd (6SPD)
diff ratio (3.28)
diff type (Getrag) (Clutch type I think)
wheel width & offset (Your 15x8s)
shocks (Stock MSM Bilsteins)
spring rates (400F/350R)
sway bar diameters (Stock MSM)
alignment (I think -1.5 all the way around.)
whp (200WHP)
rev limiter (7500)
5 or 6 spd (6SPD)
diff ratio (3.28)
diff type (Getrag) (Clutch type I think)
wheel width & offset (Your 15x8s)
shocks (Stock MSM Bilsteins)
spring rates (400F/350R)
sway bar diameters (Stock MSM)
alignment (I think -1.5 all the way around.)
Emilio, I'm going to assume you didn't experience anything similar to the delamination posted in the rx8 thread. And I know you probably didn't test them on the street. But any insight on longevity? Currently trying to decide between zII*s and these and the zII*s are known for their long lasting wear.
__________________
#69
Emilio, I'm going to assume you didn't experience anything similar to the delamination posted in the rx8 thread. And I know you probably didn't test them on the street. But any insight on longevity? Currently trying to decide between zII*s and these and the zII*s are known for their long lasting wear.
#70
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Spent the day on the 720's yesterday on the ND. 245 tire on 17x9. 80* F ambient, surface temp ~105* F
We did this twice: Three sessions/drivers back to back, close to 60 minutes of straight use, with just two 4-5 minute gaps of cool-down while we swapped drivers. The tires felt solid throughout with just a bit of a fall-off if you overdrove them for several laps, but bring slip angles back in check and the tires were good just half a lap later. Never had a point where they got greasy and needed a substantial cool-down.
Sean also did two 20min sessions separately, so we put 8 total sessions on the tires.
Rear:
Front Right - we ran CCW, so this was the corner that took the most abuse. Overall normal wear except, and it's hard to see, but the center block was worn noticeably more on the outer half than the inner half. The Front Left tire did not show the same wear:
No back to back testing with other tires so all I can say is they feel sticky. Probably not RE71R level, but quick. Very strong in braking, which is nice to see in a "street" tire. They don't talk to you much, with just a bit of a howl if you're full-on sliding. Predictable when slipping though.
We did this twice: Three sessions/drivers back to back, close to 60 minutes of straight use, with just two 4-5 minute gaps of cool-down while we swapped drivers. The tires felt solid throughout with just a bit of a fall-off if you overdrove them for several laps, but bring slip angles back in check and the tires were good just half a lap later. Never had a point where they got greasy and needed a substantial cool-down.
Sean also did two 20min sessions separately, so we put 8 total sessions on the tires.
Rear:
Front Right - we ran CCW, so this was the corner that took the most abuse. Overall normal wear except, and it's hard to see, but the center block was worn noticeably more on the outer half than the inner half. The Front Left tire did not show the same wear:
No back to back testing with other tires so all I can say is they feel sticky. Probably not RE71R level, but quick. Very strong in braking, which is nice to see in a "street" tire. They don't talk to you much, with just a bit of a howl if you're full-on sliding. Predictable when slipping though.
#73
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I've been reading some good and bad things about these tires.
Sav has me worried with -
I just need a tire that will last a whole year of occasional street/mountain driving (2000 miles) and maybe 6-12 HPDE sessions for fun/ride alongs/downpour events.
Would I be better off with the 245/40/15 VR-1 on my 15x9s for the tires relatively non-competition purposes?
Sav has me worried with -
Would I be better off with the 245/40/15 VR-1 on my 15x9s for the tires relatively non-competition purposes?
#74
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IMO, for NBs, the VR-1 should be a no-brainer. Similar speed potential to the 225 RivalS and far better life expectancy. For NAs, it's more of a toss-up, since you have to hammer on the car to get the 245/10" combo under it.
#76
Despite the tread separation reviews I picked up a set in 225/45-15. I needed a 200TW tire for a regional time attack/fast auto-x series, so they won't see the prolonged heat that seems to plague them, just a bunch of repeated short bursts. I guess time will tell on the durability. I'll be putting some mountain roads under them, and maybe an open lapping day or two as well.
Pics below are mounted on 15x8 Kosei K4R, comparison pic is 205/50-15 Federal 595RS-R on 15x7. I really like the Fed's but the treadwear is marked 140 so they weren't legal for the series. First race is this weekend so I'll see how they feel.
Can confirm the noise, they are by far the loudest tire I've ever had on this car.
Pics below are mounted on 15x8 Kosei K4R, comparison pic is 205/50-15 Federal 595RS-R on 15x7. I really like the Fed's but the treadwear is marked 140 so they weren't legal for the series. First race is this weekend so I'll see how they feel.
Can confirm the noise, they are by far the loudest tire I've ever had on this car.