Very informative info Alan Idid not know some of this myself thanks for making time to post.

Cheers lee

 

Agree with Lee, good info Alan thanks for posting.
One thing i will add is that it is possible to get 2 different shore readings on the durometer depending on the test method used.
Example. If you test at center tire wher there is less actual tire but more wheel due to the center hub, you will get a different reading than at the edge where there is more tire and less wheel. So it is crucial that the tests be conducted identically. Since most wheels differ in the center hub area i would suggest the outer or inner edge for consistency.
Bob

 

Good piece of information there.

thanks for posting it: I know that takes time to do this kind of informative posts.

 

A quick update,
I found another slot-it tyre in the bottom of the spares box

20.4 X 12.4 are also available as a treaded tyre.
The sidewall of the treaded tyre shows no DWG number, only the slot-it logo.
The tread is a ringed concentric pattern and the compound feels harder than F22.

I received these in error when I ordered F22 F1 tyres so I do not have further details on this tyre, nor do I have any idea which surface it might suit. "Slot.it" do not list the 1068/1608 f22 compound tyre (the most popular at our club) so it's not unusual to see unlisted slot-it tyres available at retailers.

If anyone uses this treaded f1 tyre, please post which surface you use the tyre on.
AlanW

 

I own a durometer. You are not likely to get accurate readings by measuring a slot car tire, something with a fairly large flat surface is needed. If you were a tire maker you would want to check a slab of the material.

 

For completeness, the F22 tyre is also available in another mold number (1219) via the Policar brand.
These are sold as "1970s formula one" and are manufactured for the Policar range of formula one cars.
The tyres fit the Policar kit and alloy-upgrade wheels (16mm bead diameter, 13.75 rim diameter) and come up to an outer diameter of 20.5mm approx when fitted.

Usage?
If the full size slot it f22 tyre raises the back end of your car up too far or makes your gearing too long , these might provide a solution without having to true the slot it F22 tyres down.

AlanW

 

A recent change to the N18 tyre.
As discussed in another slotforum thread, the N18 was dropped by Slot.IT but was reintroduced by popular demand.
As of April 2019 (approx) a different tyre producer is being used by Slot.IT
The N18 tyre no longer carries the N18 logo on the tyre wall but instead carries the marking
"SLOT.IT 1207"

I notice above that any comments on the use of n18 were absent from the initial posting.
The tyre is used as one of the control tyres for DiSCA (OxiGen) endurance events , run on Ninco polymer track.
My observations are that his tyre is whisper quiet (compared to the jet-engine roar of an E1 on Ninco) but that it sometimes has issues staying on the rim and does create large amounts of debris on the inside of the car as it wears.

The packaging still shows the full label "N18 compound DWG1207 PT1207N18"
Image on IMGBB in this link https://ibb.co/Y8tkz3p

I will be using the newer n18 tyres in practice for the Rockingham RockBull Ring 6 hour digital endurance event this weekend on the Gas Monkey Oreca LMP car.

Unsure whether the handout tyres for Sunday will be the older or newer variant.
I will Blog my experience of the event and if the opportunity arises to do a comparison of the old and new tyres, I will include those observations in the blog.

AlanW

 

Non F - nice work, and pulls together tyres old and current.
As the tyre dimension is "loose" basis, and most tyres can be fitted to multiple diameter rims- both of Slot.it and

other brands, it would be useful to also make use of the Slot.it own fitment table, which shows un-trued diameters when fitted to all applicable rims

(last part of the diagram below - "Reference by wheels dimension")
Tyre codes and raw dimensions are in the upper part along with the compounds available for a mold.
This should help also work out the fitted diameters of old tyres to multiple size rims.

 

Alan W,

Thanks for your info on Slot-It tyres sizes and shore ratings.

In January I bought a set of 1207 N18 18x10 tyres from my favorite North West retailer.
My intention was to upgrade the tyres on my Slot-It Audi LMP car, and as it stated on the retailer's site, "Fits well on GT & LMP models using 17.3 dia wheels".
A couple of months later I fitted the tyes to the 17.3 dia wheels and put aside to be glued shortly afterwards. 10 minutes later I found the tyres had split across the tread.
I contacted the retailer, who told me he couldn't replace them as they were now discontinued.
A couple of months later these tyres were back in stock, and he kindly replaced them FOC, with the comment that I shouldn't fit them to the 17.3 dia rims.

If I am not mistaken, you are fitting these tyres to the 17.3 dia rims for an event this weekend, and I would like you to let us know how the "new" tyres behave.

Regarding Shore hardness of tyres, would I be right in thinking that the more a tyre is stretched to fit a rim, the harder it behaves? I would think that this N18 tyre, stretched over a 17.3 dia rim would behave little differently to a (slightly larger) N22 tyre.
Discuss.

Geoff T

 

Geoff - the Slot.it own chart gives the dimensions of the 1207N18 fitted to 17.3 rims. It is a bit of a stretch as the 1207 mold is quite small.

However, I would not fit them to 10mm or 9.75mm wide hubs, only to 17.3 x 8mm wide hubs. The centre of the wider hubs is too wide for that tyre mold.

Your case sounds like an exception, but in general, the stretch itself probably isn't to blame for most splits, nor an actual fault in the mold seam.

Those two "causes" are only more likely to increase the likelyhood of splitting if the glue used is unsuitable for the type of compound.

I have fitted these tyres to larger diameter rims, and they are fine, but you must must must, use a slow set glue that doesn't react with these soft rubbers.

I use by choice, one of the somewhat messy, black rubberised superglues; which are suitable for a wide range of soft rubbers including
Slot.it N and F formulas,

NSR Supergrip and Ultragrip,

Sideways Pro-speed and Hi Grip, and

all Scale Auto formulas.

The two rubberised glues I know well are ic-2000 made in USA by Bob Smith Industries, and Loctite 480

I do sometimes also use a slow set gel superglue from the hardware store I have found to be "safe", or UHU "superglue", to avoid the messy back on fingers, but the rubberised glues are more consistent when gluing tyres to smooth metal surfaces.

I have even come across old tyres on cars with a rip/tear in the sidewall, and used the Loctite 480 and a bit of finger pressure to seal the split with the tyre in situ, then re-trued and used on cars with no performance degradation.

I have written a couple of tyre gluing articles, but don't think I am allowed to link to them here as I am not a forum sponsor.

 

Slotcrazy,

Firstly, the tyres split on the rims before I had the chance to glue them., so the glue was not the cause.

Secondly, I have measured the width of the recess inside the N18 tyres at 5.3mm. The N22 tyres I have been using measure 5.0mm.

My magnesium 17.3 dia x 9.75 wheels have a centre rib width of 5.16mm, whilst my aluminium 17.3 dia x 9.75 wheels measure 5.0mm

My aluminium 15.8 dia x 8.2 wheels also measure 5.15.

My conclusion from the above measurements of my tyres and wheels is that it is not the width of the wheel's rib, nor the tyre's recess width that is the cause, as they are all fairly consistent.

Perhaps Slot-It knew there was a problem when they withdrew the N18 tyres, then later reintroduced them.

I await Alan W's comments after he has stretched his new N18 tyres onto his 17.3mm dia wheels this weekend, before I try to do the same with my "new" N18 tyres.

Thanks for your input regarding suitable glue for the tyres. Loctite 480 looks a bit expensive at £31 for a 20gm bottle.

Geoff T

 

Geoff, I am just trying to help, and offering suggestion into the thread that might help others as well.

1) I acknowledged that your problem was different, - I didn't say that glue caused it at all, I said "your case sounds like an exception" and "in general ... etc" - I was proffering advice not just for you, but for the subject in general

2) I have some old 10mm rims with a wider centre ridge was well as the 5.2 of the current 17.3 x 9.75mm I don't know which rim code you are fitting to, so I was giving general advice.

Personally I don't like fitting a 1207 mold tyre to the larger hubs, even though Slot.it data that in their chart.

Must say though, I didn't see a tyre issue when I raced at Henley, and certainly no tyre changes in my 4:40 behind the trigger, for our LMP car with big rims.

As has been discussed on other threads, there was no problem with the product, they had made a decision not to make a new mold, but the cries from customers led them to re-think, and put it back into production, hence seeing the new mold with different lettering on the sidewall. In all my experience, they are pretty good at "owning" a problem with a product and fessing up when they do have one.

A similar situation has just occurred with the 1171N22, which has been unavailable for about 2 months, but they have also made new molds for that, and stock should be trickling down through the distribution chain this week

[I know this because my screams of "do not take my N22 away" were probably heard somewhere east of Jupiter in May, and I have been keeping abreast of it]

I am still using "old" N18, I glued some up on the weekend as part of a "batch" of "I really must get ahead with my tyre truing" to have some wheel/tyre combos ready for the next few projects.

They were only going onto 15.8 x 8mm magnesium rims, but they are a stretch even on those. Noticeably different to the feel of fitting 1171N22 on the same rims.

I pay about 6 quid a bottle for the Loctite ex China on EBay with free delivery, or you can get the IC2000 from SlotCarCorner in the USA for US$6.99 - you may need to ask them to calculate the postage manually for you.

A 20mm bottle goes a looooog way. When I think about it, I keep opened bottles in the fridge, but I opened a new bottle last week that had been in my drawer at least 4 months and there was no issue of it going off.

 

N18 new compound testing
DiSCA Rock Bull Ring 6hour enduro event , July 2019
Event details in the slotforum events discussion forum.

The event was run on n18 and F22
Each team given 2 pairs of n18 and one pair of F22

Our team "gas monkeys" purchased some n18 prior to the event for use during the practice session.
These turned out to be the new variant of the n18 as described above.

For clarity, the DiSCA rules for tyres state that no adhesives are to be used. The tyres are fitted dry.
The gas money Oreca is fitted with NSR wheels (non air hub) that are typical of front kit wheels fitted to NSR cars.

One of the tyres used in practice split across the seam.
This tyre was given to Maurizio who is discussing with the manufacturer.

The n18 tyres used for the event behaved exactly as the older n18 tyres.
A lot of wear, a lot of debris and the occasional tendency to come off the rim.
The tyres drive just like the older ones. I could not tell the difference.

Each tyre set was used for two hours during the six hour race.
At the end of the six hours, all of the n18 were trashed but the f22 looked like it could do more.

An upcoming event at Stafford will push the limits of these tyres further, expecting 12 hours driving from two pairs of n18 and one pair of f22. Tyre care may well be the deciding factor in is event.

Alan

 

Alan

Thank you for your very informative report on the "new" N18 tyres. This is exactly the information I was looking for.

Regards

Geoff

 

The Slot.it tires that come standard on the Slot.it cars perform very favorably to all the tires I have tried on my Home Carrera application. Which tire composition/spec comes standard on Slot.it cars?

 

C1 compound is standard.

 

C1 compound is standard.

Thanks!

 

At one time the tires that came on the cars were not the same as any of the ones that were available separately, it looks like that has changed.

 

A recent change to the tyre portfolio from Slot.It
Retailers are marking the f22 and N18 tyres as "while stocks last"
There is also a new tyre on sale, the G27, listed specifically as a replacement for F22.

Slot.it G25 Slick Tyres 18x10 Dwg 1207

It seems that G25 is the new GT "all surface" tyre, good for wood, ninco, scalex classic and sport.
Has anyone had the opportunity to test this tyre on any of the above surfaces?
If so, how does it compare to f22 and n18?
Alan

 

Hi Alan

I don't know anything about the F22 situation, but I can confirm that all N22 tyres are now out of production, as is N18.
N18 is sold out at Slot.it, N22 were still available in 1207, 1171 and 1172 last I heard, but won't be made again.

I have just a little experience with G25 - in 1172 size.

All comments below are for my situation, which is gloss wood track racing - very smooth surface, where Slot.it N22, N18 Sideways Hi Grip soft, and NSR Ultragrip are the usual choices. ie From shore 22 down to shore 15.

The G25 is a new compound, - Shore 25 in case you hadn't guessed.
It is also available in 1172, and I have so far just trued up one pair of these.
It is QUITE different to lathe true on a rotating drum.
It can easily overheat, and has to be cut very slowly. It felt like truing silicon tyres at first thought (shudder, I remember those days)

I suspect a Hudy with a diamond drum would do a much better job than the somewhat blunt, used drums on my stock Hudy, and my Tyres technology lathes.
I haven't tried them on my NSR lathe as yet. But as that has a very fine flat plate disc, I think it would struggle.

Once trued, I fitted them to a Sideways Huracan, fitted with an extra hard red chassis, sidewinder pod 25K ScaleAuto S-can motor - very torquey, so it is a high power setup.
I also gave them a light treatment with NSR tyre oil, just to help polish before track use.

They are very quiet, and I found them surprisingly predictable and smooth with no shudder, or unstable break away, but they do just have a bit less grip than N22 in the same profile.
I guess I could treat them more and lower the shore. Maybe that would help lap times.

But at this stage, I would not choose them for my situation.

I haven't had my Policar track out, to try them on that.

 

it is a pity that the N22 are out of production. They were very good tyres, very nice to true and come out of the box with a nice profile.

I used them on wood.

Do we know why they stop producing them? These G25 tyres seem hard to true and do not give any improvement in performance.

This will impact also the DiSCA WEC series. In this series, they handed out both F22 and N18 tyres and both of them had to be used.

Because the tyres should not be glues on the rims, it is important that they have a good profile out of the box.

I wonder what will be used in the future. Maybe Scaleauto sponge tyres...

 

it is a pity that the N22 are out of production. They were very good tyres, very nice to true and come out of the box with a nice profile.

I used them on wood.

Do we know why they stop producing them?

N22 is my favourite tyre. - As you say, very easy and forgiving to true. Where I can use a low profile tyre, I fit these instead of ultragrip for most wood track racing.

I think a supply chain issue, but I do not know for sure.

It will not be a problem in NZ for about 18 months at least

Gio - have you tried truing some G25 too ?
Did you use Mikes Tyres Technologuy lathe, or Westies Hudy ? Another?
I am curious also to learn more experiences.

And should you see Mike's lathe lying around club unattended, and wish to make some larcenous profit, "disappear it" down to me, and i will see you right

 

Hi Mark

I have a good stash of N22 myself but since i am not doing any analog racing at the moment I have no much reason to use them.

No I have not used the G25 yet - I even did not know they existed until reading this post - but I was aware that the F22 and N18 were going out of production. The big surprise is that the N22 will too.

I have my own Razor that I use for all my trueing. Mike is very keen on his Hudy, i am not sure about the lathe you mention.

Westies has made his own using parts from photocopy machines.

 

Thanks for the feedback guys.
It seems like the G25 has many of the same attributes as the NSR RTR tyre (red).

"It can easily overheat, and has to be cut very slowly. It felt like truing silicone tyres at first"

I will be chancing my arm on a set of G25 for an upcoming rally proxy where Urethane and any non black tyre are outlawed.

Alan.

 

Thanks for the feedback guys.
It seems like the G25 has many of the same attributes as the NSR RTR tyre (red).

"It can easily overheat, and has to be cut very slowly. It felt like truing silicone tyres at first"

I will be chancing my arm on a set of G25 for an upcoming rally proxy where Urethane and any non black tyre are outlawed.

Alan.

I really don't understand why "non-black" tyres, specifically the NSR Red tyres, are outlawed.