NSR Extreme Tires

[Audi1]

I've never experimented with NSR's Extreme compound tires before, but this COVID-19 pandemic has provided me with a little more free time lately, so I decided to give them a go.

I glued and trued them to some new CBDesign wheels, trued them up and put some laps on them. Here are my observations, so far:

On the plus side, they're very easy to stretch over the rims and they seal well. Also, on the plus side, they will true if you go slowly, Finally, once mounted and on the track, they are a fast tire and if your car happens to be suffering from tire chatter, this is one way to cure that.

On the minus side, truing is not easy. These tires are very soft and oily and if you're looking for a tire that will "burn" easily while trueing, this this is your huckleberry, for sure. I stopped several times, wiped the tire clean and proceeded from there. A combination of a very low truing speed and very light pressure finally produced a good result; in terms of both the sidewalls and the contact patch.

Also on the minus side - these are definitely low-lifetime tires! I use a sticky pad to clean my tires and as I continued to swipe the tires after consecutive 30 laps tests, more bits of rubber kept appearing on the pad. I expected this for the first few swipes, but it never ended and I finally took a close look at the surface of the contact patch and what I found is captured in the pic below.



What I found was a series of pits and irregular splits in the surface of the tires - both sides. This pic was taken after about 120 laps on a 67' routed wood track with a smooth flat latex finish. So, it's clear that the tires were chewing themselves up while showing very high traction. Note: the bits on the outside sidewall of the tire are just the "NSR" letters standing out. This was a well-trued and very smooth tire when it first hit the track. Click on the picture below for a better view.

From this, I would probably only use the Extreme compound tires for short sprints and with very light cars; figuring that the heavier the car, the more rapidly the tires would chew themselves up.

Traction is very high - in my hands, higher than NSR Ultragrips, and Slot.It N22's and N18's, but longevity is a major problem which, for me, takes it out of the realm of proxy use, since 120 laps is only about 3-4 Rounds for most proxy series.

Anyone out there with a similar/different experience?

Allan

[chrisguyw]

Most of the "Euro" guys will only use these for single events, and replace /prepare new tyres for the next race.........while they do offer good grip, (on some well used wood tracks arguably too much) for a proxy you will be taking a big (very big) gamble.........my advice for what it is worth, .....don't use for proxy events.

Stay Safe
Chris Walker

[Kevan]

They're prone to marbling half way into a 3 minute race giving you two options, stop and clean them on tape or carry on racing but losing the best part of a second per lap. Ultras are a much better option and can take a bit of oiling whilst Supergrips can take a lot of oiling but will never quite match the Ultras on a normal racenight.

[RichD]

Shoreline Model Raceways hosts a lot of proxy races, including ones that use only rubber tires. Last year we were scheduled to host one of those and I was following the results as the cars moved from one venue to the next. When we got the cars I already had a good idea of how they would perform, but one car that had been a top runner was off the pace when we did the qualifying runs, in fact it had dropped from being a podium runner to just about last place. The track had been conditioned by running many laps with rubber tires and we rolled the tires on sticky tape to clean them. Prior to the race itself I examined the tires and found that they had become glazed, none of the other cars had glazed tires and those had all performed more or less as expected in the qualifying runs. I wiped the tires down with contact cleaner and that removed the glaze. During the race the performance of the car was about the same as it had been earlier in the series. It was unfortunate that I had not noticed the glaze earlier so that I could have contacted the race director asking for advice on how to proceed. Possibly I would have been told to leave the tires alone. If a water based cleaner had been available I would have tried that first. At least I knew better than to use any product with oil in it.

[Brumos RSR]

Allan, if you recall during the 2016 Group 5 proxy, my tire (Tire Gate) was somewhere in between an Ultragrip and an Extreme, testing was great for hot lapping around at home alone on on a fresh track. However during proxy racing the tires would pick up what's put down by the other cars during the lane changing process. This made the car loose, and bumpy while heading down the track. I never forget as I was the on the pole at the River Run with a blistering 5.7 pole time (fast back then) only to finish 16th as the car fell off after the 1st minute of each session. Enjoy it for fun but we want to compete against the best Audi1 build on race day.

[munter]

Before taking the hub and tire off the truer....try a rag soaked in fuelite/naptha on to the tires running surface with the wheel spinning.
This can sort of melt the surface into a more homogenous/smooth surface which may help with the small chunking as they run.......may help???

[radarek]

Nsr calls this tire “Qualifier” for good reason...

[ra7c7er]

I read on a euro forum that guys are using these for sub 30 minute races. Or as optionals in endurance racing. I guess to try and catch up after a unscheduled pit stop (their was no clarification on the thread). They would be neat in a spec race where you'd have to manage the tires over a hour or something.

[Mitch58]

I've never tried the extremes and only a couple of sets of ultras. most of mine are Supergrips, I found my lap times comparable to Paul Gage urethanes. For a long time I was only using urethanes, but as more proxies started calling for rubber tires I started experimenting.

[Kevan]

I read on a euro forum that guys are using these for sub 30 minute races. Or as optionals in endurance racing. I guess to try and catch up after a unscheduled pit stop (their was no clarification on the thread). They would be neat in a spec race where you'd have to manage the tires over a hour or something.

Extremes are the antithesis of endurance racing tyres

[ra7c7er]

Extremes are the antithesis of endurance racing tyres

That's what I was thinking. I can only think of a few reasons you'd have them as your optional set. Late race when you are pitting (for whatever reason) within 15-20 minutes before the end of a race or after a unscheduled pit stop but before a driver change when you will be making a driver change and stopping again soon anyway. Basically using them to either try and gain an advantage at the end or to make up a little ground when you already in a bad spot. IDK but its interesting. I really like the endurance races and enjoy seeing the different strategies teams use.

[Kevan]

They'd only be good for about a minute or two at the most, they marble up real quick.