Hoyt St UAV/ROSA trucks... on a DIY.

Righto cocks! I have some wonderful love to spread about the Hoyt St UAV trucks

The kind folk over at @hoytskate donated these beauties to me in return for my opinion on them, so I’ll just dive right on in.

Fitting

My plan was to take the @Savage1 TKPs off my demonseed and replace them with as close to the same setup as possible using the UAVs.

It went pretty smoothly except I needed to extend the mounting points of the trucks for wheel clearance.

Ended up moving about 20mm forward at the front, but the back was ok because the rear truck doesn’t turn as much as the front.

The first thing that struck me about the trucks is that they have pockets cut into the baseplate to accept a standard 10/32 nylock nut. This is standard skate hardware size, but imperial stuff is not common in Australia and so I really only use metric hardware. An M5 nut is much smaller than a 10/32 nut and does not get captured in the slot and the slot doesn’t give enough room to get a tool in to hold an m5 nut.

BUT

An M5 bolt will be accepted by a 10/32 nut, so all is merry…

Next part was to fit the wheels. Here in convict land, the only 10x22mm bearings i can find are only 6mm wide rather than 7mm. The trucks came with a perfectly sized spacer… had i been running correctly sized bearings. So i printed some spacers. I also needed to print some custom spacers for the rear.

By the time I allowed for my Savage pulleys to clear the mount and align with the pinion, i wasnt left enough room for the nylon to engage, so I loctited the rear axle nuts.

It’s definitely worth noting here that the axles that came on the trucks that I received will only work for urethane and i’m told that the Hoyt 5 inch will work on them as well. But otherwise the axles aren’t long enough to run regular pneumatic hubs.

The spring loaded belt tensioning system seems pretty cool, and worked well to set up, pretty cool to be able to tension belts on nylocks, would allow you to wheel swap on the go, easily swap belts, and no loctite! :partying_face: i had issues here, but we’ll get to that later.

The one thing that got me about the tensioning system is that the mount only moves in/out about 5mm. This means you need to have your belt length calculated quite accurately, there isn’t much room for error.

Another noteworthy point is that the mounts only allow for countersunk motor bolts, not cap head bolts like a lot of other mounts.

The mounts are chamfered nicely to allow the phase wires to exit along them, very nice touch.

I think that’s about it for fitment!

The Ride

Goddamn. I’ve only put about 50km on these trucks, but I’m in love. They are considerably wide (hanger length is somewhere around 300mm) but the agility out of these trucks is wild.

I’ve taken the doggo on a few runs and also did a sneaky pub run on it and these are the kind of trucks that are just a joy for every day riding.

They have a REALLY good turning radius compared to most boards that I ride but also hold on really well at speed.

I would issue warning though that you’re gonna need a certain amount of skill/ankle strength if you wanna do considerable speeds on these. Compared to the Savage TKPs that I just took off, these trucks require a lot more focus when in the upper echelons of speed.

Oh, I almost forgot! The belt tension thing. During a spirited run to the pub and back (20km round trip) the motor mounts lost tension several times. I tightened them up as hard as I could and have done about the same amount of riding since and they haven’t come undone, but Hoyt have assured me that this has been rectified since.

To sign off on this, I’d like to thank @hoytskate very much for the opportunity to try these trucks, and i’d also like to congratulate them on a job well done, these trucks really are a joy to ride, I was pleasantly surprised.

Cheers :beers:

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Interesting, I would have expected the opposite when comparing RKP to TKP.

The M5 nuts not fitting and short axles seem like dealbreakers for DIY, but having ridden these trucks myself on a UAV – yeah, they feel good. I wasn’t able to test high speeds with them, but took them up to 25mph and they felt just as stable as at zero. The krank bushings made them feel a lot like my hexl tkps, just more stable.

Personally I’m planning my next build with split angle RKP trucks with rake, which is exactly what makes these trucks special.

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Yeah i don’t know if its just me or what, but i feel a lot more comfortable on the savage trucks at speed (50kph+). On the savage trucks I have 90a barrel boardside and 90a cone roadside for the front truck. On the UAVs i have 90a fatcone boardside and 90a barrel roadside. I get heaps more turn out of the UAVs, and so it feels a little sketchier at speed

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Oh I should mention as well, this setup is suuuuper quiet. I’m running maytech 6374s, i haven’t used sealed cans in a while so that might be the difference, but I have a feeling that the quietness is because everything is just aligned really nicely.

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Thanks for the review! Glad you liked them :slight_smile:

We’re going to have to double check this, and if this is true, order longer axles ASAP.

Hmm, I wonder if some clever geometry could be had that allows for both…

Until then, we’d be happy to include hardware with purchase if asked

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Wow even on cones that’s interesting that the UAVs (speaks heaps about the UAV though) have more turning capability, like @rusins i would’ve expected the opposite. Wonder how double cones on the TKPs would do.

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Had thought about this previously but only just now remembered after reading this thread, why can’t we just have tapped wire thread truck baseplates so you don’t need a nut

I think a major part of this has to do with after crashes, you might fuck up the bolt and have it very difficult to remove, but that’s gonna be the case anyways.

There might also be concerns about cross threading the baseplate, but at that point you could just use it as a regular hole and install a nut.

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some* baseplates do have that. Trampa i believe is one.

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Yup they do

see i knew i couldn’t be the first to think about it…

for those who have experiences using that system, how well does it work?

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Well most baseplates are not high strength alloy steel, so that’s a downgrade. Also depends how thick the plate is, if it has enough threads. You can try this yourself by tapping existing thru holes to the next size up - quite simple and quick.

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giphy (20)

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For the ones that are literally machined from 7075 aluminium i don’t see why that would be a problem

It doesn’t literally matter what grade of aluminum you use - threading soft metals is a bad idea for repeated, structural fastening.

But again, do it. Tell us how it goes.

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Also you’d then have to threadlock the bolts instead of using a locknut with nylon to keep it secure. I prefer nuts.

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For reference.

We’d like to take feedback on which length axles we should add to our options

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For DIYing, having 50mm axles available the mountless hanger (front) would be ideal.

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Including or not including threads?

Full axle length, so including threads. What BN has is perfect.

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@Stealther, threaded holes in the base plate is 100% wrong for many more reasons than I care to share, and @hoytskate surely knows that.
That aside, I would recommend no slots for the lock nut at all, for many reasons…
It is not difficult to use a wrench on the nut while tightening the base to the deck, and is clearly adding some confusion with #10 screws vs M5.
Most importantly, adding those slots is adding to the cost of the parts being made.( and for what added benefit?) The manufacturer making these, is having to use an 8mm endmill, protruding at least 25-30mm from the tool holder to make these. When the end mill protrudes that far, (Diameter vs length), the machining times are longer.

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