Sunday, April 5, 2015

Achilles 123S testing... Track racing trial and testing!

The Achilles 123S is a tyre that has gone unnoticed by many in Singapore and Malaysia which is surprising since the older version of Achilles 123 was the official tyre for the Sepang 1000km Race in 2009 and this tyre has even been run by the winning car in the Formula Drift event in Singapore in 2012. This lack of notice is even more surprising since they are currently being run on the leading Formula Drift car piloted by Daigo Saito who dominated Formula Drift US Irwindale in October 2014.

Check out this cinematic clip of Daigo with Achilles Radial team!

 
 

Seeing how much promise the tyre has to deliver high performance at a surprisingly affordable price, I decided to try them out to see if they would actually be able to match up to the current top reference tyres in my mind: namely, the Advan Neova AD08 and Hankook Ventus RS3. The Advan AD08 delivered super sharp response with great progressive grip rain or shine with a relatively moderate fall off in grip over the heat cycle while the Hankook RS3, although cheaper, was super sticky when fresh but tended to be a bit lacking in feel, be rather tricky to drive in the wet and had a fairly steep drop off after a few heat cycles. Where would the Achilles 123S end up in comparison to these 2 great tyres?

Here's some shots of the super aggressive tread pattern of the tyre





Although I could not get my hands onto a 255/40/17 Hankook RS3 which has an advertised tread width of 9.6 inches for comparison, I got the next best thing to compare with which was a 255/35/18 AD08 which has an advertised tread width of 9.9 inches so its clear to see the 123S, despite being slightly narrower runs very wide indeed!

 
 
 

When you don't have a ruler on hand, the key comes in handy to measure tread depth! This is about a 5mm tread depth which is optimal for out of the box racing use.


Referring to the Achilles 123S page here, we can see the major benefits touted:

1. Twin Centre Grooves Design
2. Rounded tread design
3. Rim Guard Protection
4. Solid Centre Rib
5. Highly strengthened block and strong tyre shoulder design

The combination of all these attributes are meant to deliver a tyre that excels on the street and track racing performance. Considering the reasonable price and the multi year warranty that is extended on the tyre, most buyers of these tyres should be pretty comfortable knowing that choosing this tyre won't overshoot their budget or compromise on safety. Track enthusiasts like myself, however, would really focus on the both daily driveability and the ability to achieve good track timings when running these tires. So after a few weeks of driving the tyre around on the street, it was off to the track!

Heading down to the 9tro'us Track Day , I got a good feel of how the 123S would perform in the scorching hot weather on that day and even managed to get some data on the performance of the tyre via my RaceLogic Performance Box which gives me the grip numbers via a G force readout. Let's break down the numbers into a performance department comparison versus a currently well regarded tyre for tracking namely the Hankook RS3 Z222 by making reference to the average G forces generated over a series of runs done.

A) Straight line braking on the front and back straights:
In terms of heavy braking from high speed, both RS3 Z222 and 123S perform at a very high level and exceed 1 G of brake force and there is not much gap in terms of grip potential between them both.

B) Low speed corners:
The grip difference seems to favor the RS3 yet the 123S is only separated by a mere 0.1 G meaning this difference is really slight and might only be truly apparently driving when you are seeking that additional couple of tenths of a second.

C) Mid to higher speed corners
Considering that the aerodynamic effects dominate at these speeds compared to mechanical effects, it was relatively more easy to get stable results to spot a difference as spikes in readings tended to be slightly less. Once again, the difference was similarly slight but there was a clear consistent bias to RS3 Z222 having a higher grip.

Overall despite me having mechanical issues which resulted in my lap times being rather below expectation, I was able to get some valuable feel of how the tyre performed. Firstly, the feel and response of the tyre were at a very high level and definitely close to the excellence of the Advan AD08 leading me to be very confident to push the limits as I had very good feedback through the steering. Secondly, the tyres were sticky and maintained their grip well despite the blistering hot conditions during which many tyres would have succumbed to. Thirdly, the outright grip was very close to the super stickiness of the Hankook RS3 as validated from the data generated. Even my friend Gerald Tan who races at a pretty high level commented on how nicely the tyres seemed to perform!

Here is a video link of how exciting the track day was! Can you find my car in there? ;)


In between this and the next track day, I did a fair bit of daily driving which gave me a chance to experience the tyre on day to day driving use. During the dry weather driving, the noise generated from the tyre was on the high side but for an enthusiast driver like myself, the noise was really nothing new and pretty much in line with what most tyres of this category would be like. For the wet weather, due to the shallower tread depth, one had to be cautious not to get into deep puddles as aquaplaning would occur. Even so, the tyre was very communicative throughout and would "remind" me how close to aquaplaning I might be getting close to. Definitely a tyre that I had no problem living with for daily driving use.

The next trackday I attended was the (12 Sept PG) where with the help of the tyres, I managed to snag 1st Place in the Normally Aspirated CCT challenge! I had a leaky exhaust manifold to contend with which slowed me down a little and my settings for alignment and damping were off the mark leading to me being lacking in confidence (the walls are pretty close at Johor Circuit so I'm not afraid to say I have good reason to be really conservative!) but despite that made some improvement to my personal best.

Here are some pictures of all the fun I had at the event! Grassroots motorsports at its finest...
 


 






 

 
After the track day, the tyre was fairly worn but in a rather even manner as you can see from the pics below:




I did, however, have an issue on the final few laps of the CCT which caused me to have unstable handling when applying or backing of the throttle. I found out that the tyre had developed a bulge which you can see from the pics and video below.

Watching this video u can see where the block bulges as the tyre rotates



These two pics show a close up static shot of the bulge





The development of such bulges does not mean that the tyre is in any way lacking in quality as tracking the tyre with high camber like I do puts huge stress on the car especially since I tend to run about maybe 20 hot laps or more at a go even on a worn set so from time to time, such faults appear. I had used another set of 123S all the way down past the tread marker bars and no such bulge had developed so I'm actually very confident in the tyre quality and construction. 

I've taken pains to deliver a fair and transparent review of what the strengths and weaknesses of the Achilles 123S and I hope this has been informative to those who want to pick a tyre and are presented with this choice. I strongly recommend this tyre to any of my friends especially those who enjoy going to the race track as it's balance of both excellent performance and great affordability make it a powerful proposition so I have no reservations in doing so. Do look forward to see me use this tyre more often at the next track events and maybe even competitions!


 
 
Credit to the following for their strong support:
Achilles Radial
Ardeca Lubricants Singapore
Wasp Composites
YHI Singapore
Counterspace Garage
 
Media credits to:
AutoMoment / Shot by Royston  for the pictures
Rev Magazine for their coverage of the PG Trackie event
Aaron Hia for his pictures
BROOKSFILMS for the video of Daigo
525 Studios and 9tro for the video of the 9tro'us 2014 trackday

6 comments:

  1. Hey! great article. very helpful. The information is very well written and very well explained. Thank you for sharing. carbon fiber bicycle wheels

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  2. That bulge looks like it developed due to improper alignment spec.

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    Replies
    1. Hi, you have a VERY sharp eye. Indeed the probably cause was overheating with compromised alignment & tyre pressures. Sometimes stuff like this makes people question the tyre but in many cases its a user fault as opposed to a product fault.

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  3. This article sounds sooooo sponsored.... lol
    Anyways am gonna try this 123s once my AD08s die... hope to be surprised...

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    Replies
    1. Hi Kenneth, I've tried my level best to keep the information as objective as possible . It's interesting to note that post this article improvments were done to the compound to increase the grip so the latest compound of 123S is apparently quicker. I've gotten myself a set to try out and will be updating the compound change in a new blog post . Hope you found the rest of the blog a fun read!

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  4. Thank you! Do share this post with all those who might benefit :)

    ReplyDelete