Any interest in the kart tires? Guessing you’ve tried them?
My bank account says yes
was gonna ask.. tx.
i was also curious why do the front pairs and rear pairs which were close the same temps pairwise during the race, stratify into 4 temps after the race. … was it half in the sun.
Yeah, I have some thoughts on those. I think they’re the future of the sport… emphasis on future.
The rubber compound that you can get them are miles better then anything else we’re racing on esk8’s. They all have buttloads of grip.
That said…
- Putting them on an existing setup, you end up with a different steering/truck geometry because of their size. Most notably is a very negative front caster (causing high-speed instability, especially under braking).
- They also raise the standing platform, so you’re standing higher in the air. This changes the tire loading, causing the outside tire sees a lot more load.
- Gokart tires track like they’re on railroads, they’ve got so much grip. However, I’m not sure this is something we want on a racing esk8… I think we want tires that allow for some slip angle. I race BRP tires.
Going around a corner, I maintain balance atop the board with the pressure I’m putting onto the tires. I press harder, they slide/slip more, pushing out from under me, to the outside of the turn. If the board gets too far away, my pressure decreases, causing the board to slide less(turn faster), moving it back under me. There’s dynamic stability with that.
When riding gokart tires, I feel the opposite… the more pressure I put into them, the harder they wanted to turn? Dynamic instability. Sounds silly, but I felt like I was one wrong move from “catching an edge” and high-siding.
3a. I have a suspicion that this is why a lot of stooge riders have been riding wet/rain tires at races. The tread pattern allows for much more flex/rotation of the rubber, helping with dynamic stability when cornering.
3b. This also is made worse by (1) and (2) above. - I think the optimal esk8 tire size is/will be 9~10". Big enough to roll over cracks and increase the contact patch area, while not being too heavy. Bigger then what a lot of us race now, but not as big as a lot of gokart tires. Hard finding race tires of this size though.
IMO, the success we’re seeing from gokart boards right now are from the rubber compound being miles better, despite all the drawbacks in other areas. It also explains why people like @HAIRYMANJACK are still able to compete with gokart tires on BRPs (better dynamic stability)
To fully utilize go kart tires, IMO we need to rethink the boards from the ground up (and why I’m super excited to see what @Dinnye and others are cooking up)
Hope you enjoyed the word salad. My sample size for gokart boards is very small, I have a very unique riding style, don’t have a binding, and this is a lot of speculation on topics I don’t fully understand. So entirely possible I don’t know what I’m talking about here.
Yeah… like @jack.luis says I bought a set of his swiss cheese hubs so I can experiment with stuff. Not sure exactly what/how yet.
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lol. that’s funny now that it’s been decoded for me. 
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Checking my helmet cam, they were both in the shade
It was a CCW track, so the right tires would/are being worked much harder then the left side.
I think this led to a lot more heat being generated in the core of the right tires. Why this causes the L/R surface temperatures aren’t more different, I couldn’t say.
Maybe the airflow over the tires cools them so much that their temperature is primarily set by the amount of “new” heat generated on the surface (by sliding)? and the L/R tires are always sliding roughly the same amount because of the fixed hanger?
This would be supported by the cooling on the straights.
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I wonder if you can retread esk8 tires using gokart tire rubber. 
Awesome to hear your opinion and thoughts on them. I’ve got just a few laps on them on an unfamiliar board ( Dive Bomber | a @Dinnye Inspired build ), so it’s been great to hear what others think. I’ve been trying super novas lately and am enjoying playing with a new tire. Also bought a set of the cheese hubs to play with. If they’ll fit on my v6 I’d like to try em out using my buddies kart tires as a cheap as possible way of trying them. If I’m digging them I’ll probably get a full setup from SRB. I’m a little leery of using the 10mm axles with the kart stuff. But should be good for testing it out so long as clearance is all good.
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What was you’re experience? similar?
I only had a really short time with them and the stance on the board I got to try them was so different than my own in every way it made it tricky to really get a feel. But the feeling I did get was that they conformed well over bad track surface, they had what felt like a lot of grip, you don’t notice their size as much as you would think, they are ridiculous looking at first but it grows on you, loading the car will suck more,
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I feel like it’s worth writing down my experience against your points
- Actually I didn’t notice the front negative caster to have any bad effect on the flexy setup. I haven’t had a single wobble on the kart wheels after I moved to the flexy geometry (other then the one time when I fully leaned back to brake but the remote cut out and didn’t brake). Front wobble on braking was more of a thing the Linns and Supernovas for me. But the first iteration that you saw in May did make me wobble out violently and crash on the stiff chassis at low speed, having been setup for good turning.
- Definitely true and I feel like I’d actually benefit from running positive camber because of it.
- The railroad feeling is definitely there, and (at least on a torsionally not very stiff setup) causes some weird board walking under you feeling when cruising at lower speeds. I don’t notice that same feeling on the track at all though.
Regarding the slip angle. Depends on setup. From my experience, in a setup you want either just flex, or just slip angle, if you don’t have either or have both then it doesn’t handle well. For a stiff setup like Moe’s chassis’ you want slip angle for the exact control that you described. When I started testing around May, I was on a stiff chassis and the zero slip angle did not feel good. Then I changed back to a flexy chassis after my crash in Prague and the zero slip angle of the kart wheels felt like they synergized with that setup.
On the stooge setup it isn’t so much that the more you push the harder they turn, more so that coming from BRP (and tbh most other esk8 tires also, but especially BRP), you are used to huge slip angles, which significantly reduce your steering, so with the kart wheels your base level of steering is already higher than expected unless compensated for. The wet tires feel like most esk8 race tires (but not BRP) in term of slip angle. There’s definitely some, but it isn’t an unreasonably large amount.
There’s also a tiny bit of flex in a stooge chassis which can cause the more you push the harder it turns feeling.
There’s two angles to this. I feel like a huge part why you didn’t like this is familiarity bias - you are used to the stiff deck high slip angle setup, and controlling a flexy setup with low slip angle requires that you relearn how you change pressure in a corner, for which you definitely need a bit of time on the board. Also, if the bushing and truck angle setup was done without being aware of and exploiting this behavior, I see where you would be coming from.
The dynamic instability you are describing comes from a positive feedback loop essentially: the more you turn the more pressure there will be so you turn even more. It can have an overall positive impact on ride feel if baseline turning is adjusted.
On the other hand, once you get some time to rewire your brain for the different control of a flexy low slip angle setup that’s specifically tuned with this in mind, it completely changes what you think of this. The flex causes truck angle increase when the board is loaded, thus creating this exponential ability to turn. This means that you can run a lot of lean / turn - a very low truck angle setup - while still being able to turn very well exploiting this positive feedback loop. Thus you gain a lot of baseline stability, and I am actually more confident at speed on this setup compared to a traditional setup, even before we consider surface imperfections to be a thing, which these handle way better.
I was initially running a stiff WFB bushing setup in this, which felt great overall. Supporting, very strong center, comfortably doing a 180 turn without tire slip in the width of 2 parking spaces at speed (5m) with still more articulation left in the truck.
Recently I’ve experimented with a soft and very divey WFB bushing setup and even that still has more stability then my esk8con setup on supernovas did that couldn’t turn as tight as the hard bushing setup does on the kartboard. So far I did a 180 with no tire slip in about 1.5 parking space width, and that still didn’t max out articulation on 45” wheelbase.
- As long as we race on tracks where there are cracks (which seems to be most of it), kart wheels are the perfect size I think. They are so much more forgiving over cracks, and you can still achieve a board with reasonable weight with them
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Fascinating stuff, thanks for sharing.
This is a fascinating hypothesis, I’m going to need to think on this one.
From a theory perspective;
More pressure on a flexy deck decreases the turning radius, making the board want to turn under you. The opposite is true as well- less pressure makes the board drift away from you.
I would think this makes it inherently unstable? (Less pressure => board drifts outside => causes less pressure => etc.)
This might just be me rationalizing the familiar.
I also love flexy decks. But thinking back, the best feeling setups have always been on slidy tires (ex. BKBs, NOVAs, kendas, etc)
I can totally see the flex being useful for “”“power pivot””” short track turns, as I love riding my Tynee Explorer like that. However, I’m curious, How does your flexy/no slip setup feel in sustained high speed turns?
Entirely likely, I can see that
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If it were to drift outside, your ankles would naturally apply more deck lean, bringing it back under you.
If flex and high slip angle tires are mixed, that did cause some oscillation in sweepers for me, as they fight each other on different orders. The positive feedback loop of this “power pivot” effect makes the steering reaction of a flexy deck a bit progressive feeling, while the slip angle is more or less linear feeling but works in the other direction. Mixing the two did create weird oscillations in sweepers, especially on surfaces that have less bite.
Feels very steady in sweepers like the long high speed turn at Pardubice, and even handles the compression / decompression of the sweepers into and out of the lower straight at Kartplanet fine.
This “power pivot” effect is much more noticable when snapping the board into the turn very suddenly, the effect feels less aggressive if you enter the turn by slowly applying the deck lean.
The only corner type where this setup doesn’t feel perfect is an aggressive multi chicane / slalom at a speed that I would define as inbetween medium and low cornering speed. Like the one on the right side straight here, and it doesn’t help that it was a relatively narrow track with 1 meter high stiff tire walls which I really didn’t want to crash into.
Which is the bottom straight in this track setup picture
This is because switching the direction very suddenly does induce the “power pivot” effect, which means higher truck angle / lower deck lean / less support from the bushings, leading to a lighter steering feel. At higher speeds on wider tracks even in this same corner type you always have enough time to not just fully snap the board from one direction to the other in an instant, so you don’t even really feel this effect.
Even for this specific worst case scenario corner if you are aware of it then it isn’t really an issue, but the first time in this specific corner type at this speed does feel a bit weird. Pretty sure it could be compensated for by higher rebound bushings, but I like the low rebound and low friction characteristics of WFB everywhere else.
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Some incredible chase footage of the apex pro final, flown by Ryan
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Nice battle between you and Redbeard. @HAIRYMANJACK looks on another level lately 
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Replacement GPS Module arrived. Interestingly, it has a different form factor then the stock one.
Some educated guesses later, I have it wired up.
Also took the opportunity to remove the broken glass, reattaching the screen the same way I did with my other megan
Additively, not the prettiest repair job. looks like it’s been through a couple wars lmao
There was no chance at getting a GPS lock inside my apartment building, so I rode down the street to an empty parking lot to test the repair.
BE-122 spec is cold start lock in 30 seconds. but mine took nearly 15 minutes. Even then, it was intermittent and only max of 5 sats (instead of 8+).
I have a hunch I need to leave it for like an hour before it’s in a happy state. Hopefully this gets better over time.
The red PPS LED on the BE-122 gps was/is intermittently flashing a couple times. I think that means it's in repair mode?
The only information I could find
Suboptimal GPS performance aside, the recorded metr log has a download button. Problem fixed, woot woot. Thanks @janpom
Grabbed a photo of the board while I was waiting. Neat seeing how much it’s evolved over the past two years.
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I need one.
Kyle (San Fran) visited for the weekend and was killing it on Ankle Wreacher. Is really cool to see, i never get to see it pushed hard
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my man!