Indeed. the hazzle of gear drives is to change gearing though. so basicly a 1:6,25 gearing would make my 8" tyres useless getting a top speed of 40kph. that means i’d have to change the motor gears every time i change wheel size 
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My opinion is very close to that of Seabjorn
My setup is as follows (so you can judge it):
- 2 SK3 6374 149KV sensored
- gear ratio 5:1 (chain)
- battery 12s6p molicel
- VESC config current: motor 110, battery 80
- 10" tyres (C-248)
PRO: Comfort in off-road even on more difficult routes, with superficial roots and holes. Less rolling resistance. Less torque, but easier to manage.
CONS: Just say that each tyre weighs about 800gr. So you can forget about agile driving with fast jumps and accelerations.
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Damn you slam 110 amps in those motors without overheating them? In that case, why in the hell do I use 80100 motors 
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Maybe because the sk3 has lower 149kv than 80100?
I don’t know!
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Shipping kills it for me, it’s like double the price of 4 tires last time I talked to them
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Nah that’s not it, generally a higher KV motor of the same size can handle some.more amps.
Very impressed that your sk3’s can handle that. I tried 100A on my old 6384 130kv APS motors, they didn’t like it to much.
Anyways sorry for derailing, topic was about rubber and not motors
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@ixf Did you ever get an answer to this, or does anyone else know? I want to pick up a set of MBS 9" tires, but if I can save some $$ and use 8" tubes, that would be super.
I rode with 8 inch tubes in my 9 inch tires for a few days and didn’t have any issues… Who knows long term though. I didn’t put them through rough use during that time, and I feel much more comfortable about using 9 inch tubes long term.
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I ponied up for 9inch tubes. I eyeballed them and i think the inner diameter was different. Since i use 3ds hubs that wont work for me. I can see them working for trampa or 5star though but again, you’ll be stretching the tube pretty thin as you inflat them, probably not the best
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FYI, for those looking for 9" tubes but not wanting to pay $13+shipping from MBS.
These shipped via DHL and got to me in like 10 days or less (don’t exactly remember, but was surprised by their promptness).
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Hey kids.
I’m pondering going to 9 inch on the tow truck.
Currently running the clever knobby 200x50
On rockstar II hubs and a chain sprocket.
I use this deck now a lot to tow the bike trailer on family rides.
And I do some solo rides as well and going on little dirt trails just shakes the shit out of me.
So I think I might end up with a more comfortable ride on the 9s
As much as I watch trampa you tube and wanna do jumps it is not really happening for me anytime soon.
Can anyone confirm the hole spacing on the Rockstar II is the same as the Fivestar Hub.
Looks like it but I wanna verify.
I am US based.
So this is looking to me like the cheapest way to go to 9.
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I confirm the spacing is the same.
Those t2s are HEAVY. Be ready for a difference in feel for sure. Much more grounded.
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Are you sporting the T2s?
Yep on the newest board. I can barely do a wheelie with them on the front end. They’re honestly more like 9.25".
They definitely roll over nastier stuff though. Tree roots and sunken grass spots are significantly less sketchy.
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But jumping is decent
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I haven’t gotten to try them on my lighter jump board. It’s on my to do list for sure.
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I do jumps with 9s that I just got from harbor frieght. 34 for a full set check out my post
Includes: tire, tube, and hub for 5/8 axle
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I’ve held those harbor freight ones in my hand and didn’t like the feel of them. They were super unbalanced on the shoulder bolt I brought with me and I didn’t think they’d feel safe at speeds.
I’ll get around to trying them on a jump deck one day for a better comparison.
Noticeably heavier in the hand, but I have a feeling they are a bit lighter than t2s. And yeah they are slightly off balance but I aligned the valve stem with the light side of the tire(tire on hub without tube) and the only time it ever wobbled on me was at mild speed 10 to 15 mph.
Once I get some slime in them they should ride true
At that price I had to make it happen haha. Can always glue some dimes in your tire
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And still save money 
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