The BEST and FIRST Qulbix Raptor mid-drive build!

Thanks for the info, what you're doing is awesome. I can't wait till we get some of these bikes on the forum, I know offroaders especially are gonna love them!

I've sourced mid drive motors that go up to 35kW and will fit on this frame. They still weigh far less than a 3kW hub motor

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Cool, I'm looking for one. Something 10-15lbs, under 7"x7", and low kv (like 30) would be awesome. The ability to take 10kw would be serious shit imo considering how my klein has been at 6 and 7kw. (Honestly at that point it's all about feeling safe with all the torque geared one speed. The only thing that I feel safe with right now is using a 3spd switch.) I was considering the denzel 7.5kw but a slower wind would be better imo.

Plez PM me then (pricing etc) when you get ready to do some of those hubs for cassette?

The motor supplier pitched this motor to me yesterday:

KV: 28
MAX POWER: 40-45KW
Continous power: 25kw
MAX AMP: 200A
ESC:200v/250A
MAX VOLT: 200V
NO LOAD CURRENT(20v testing voltage): 2A
RESISTANCE (mOhm): .35
SIZE: 202x 80 ( 7.95" Dia x 3.5" W )
Stator/magnet: 36/40
WEIGHT (kg):6.4 (14.1 lbs)
SHAFT: 20mm hollow shaft
Thrust: 90kg
Torque: 85Nm maximum continual

The diameter is a bit large but the width is great. There is a range of motors down to a 2200 watt motor that weighs one pound!

Getting the rear hub designed and made is no problem. The difficulty is in making just one (expensive) or making a run of ten or so and then I'm holding parts again. I agree that a hub with two six bolt flanges on the left and a free hub ratchet on the right is ideal. It needs to be a 165mm or 170mm width in order to fit everything and still have decent spacing on the spoke flanges. 135mm would be what most people want but that's stuffing 20 lbs of shit into a 10 lb sack. For 135mm you're looking at a normal disc brake hub with the sprocket on the rotor flange and a rim brake.

If there is enough interest in a 165/170mm wheel hub with two six bolt flanges on the left and a free hub ratchet on the right I'll have a run made.

nutspecial said:

Hell yeah! And if someone wants even more power just gear down to like 25-30mph top speed 5kw. Should be bulletproof John, and a front hub would be awesome to add in at that point for topend and 2wd?

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Not sure if you were being sarcastic... not that it matters.

2wd does offer more traction. If you sit back and ride the bike like you're cruising at the beach = No it doesn't offer more traction. It requires leaning forward like you are countering a mono from the rear wheel to keep the front down. For me generally if you stand up on the bike and put some weight on the handle bars the front stays pretty planted. The motor even when not used works well to be able to put more counter weight to the front lifting making it easier to pour on rear torque.

With a speed controller I think the front motor would be pretty dam terrible.... The phase runner torque throttle makes it easy to use and only pours on full power when it is realistic, not from a dead stop.

Anyways this is not about 2wd... just had to comment on what I thought was directed at me.

I have bought a raptor 76 too now to replace my crabbed and twisted DH bike.

What I like about LR raptor build as opposed to the recumpence one is the shorter chain length and being on the arm meaning the chain dance should be a non issue. The other cool thing is that the motor partially hides behind the chainring, and should be partially hidden by legs much of the time, making it a much more stealth looking bike to onlookers as you scoot by.

I am just wondering about the motor drag and the flip side regen possibilities.

Maximum tyre width looks like a regular bicycle tyre? 2.5' still?

Very interesting to follow!

LightningRods said:

The motor supplier pitched this motor to me yesterday:

KV: 28
MAX POWER: 40-45KW
Continous power: 25kw
MAX AMP: 200A
ESC:200v/250A
MAX VOLT: 200V
NO LOAD CURRENT(20v testing voltage): 2A
RESISTANCE (mOhm): .35
SIZE: 202x 80 ( 7.95" Dia x 3.5" W )
Stator/magnet: 36/40
WEIGHT (kg):6.4 (14.1 lbs)
SHAFT: 20mm hollow shaft
Thrust: 90kg
Torque: 85Nm maximum continual

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Do you have any pictures or a possible price for something like this?

They list the price at $1,172 plus shipping for 1-3 of these.

Wow, if it's real that's amazing. I never heard of an RC motor w/ that low kV and that much power???? I'd think Matt would have already been using one so he didn't need all the reductions for his RC builds? I kinda wanted a sealed inrunner like bigblock/bht tho, someone else can be first with these!

This is a completely different type of motor than Matt has always used. Way large in diameter and heavy compared to the Astro 3220s that have been his motor of choice. It's a 35 hp motor meant for ultralight aircraft. This is much better suited to a motorcycle frame.

If it's for aircraft, I just wonder why (or how) the kV is so low? Same uncensored type, same lack of cooling on a bike, it just seems bigger? Anyway, 35hp on a 100lb bike is 'Luke' style- I'd fricken kill myself lol.

The low kv is to get the rotational speed on the propeller where they want it without having to use a reduction gear box.

Yeah, I'm more than happy to leave <3 lbs/horsepower to other people. I'm looking forward to running around 1/2 that power level. That will satisfy my personal need for terror.

45KW ? that is insane..But im not sure about the cooling, because it looks tiny for that Power.

25kW continuous, but yeah 25kW out of 14 lbs is better than an Astro Flight 322O's 6kW out of 4 lbs.

Re> John: missed your post. Yeah I noticed you're building on a q76 w/ maybe a big rear hub, but prob are considering this too if you're here. I think you'd like it, and could always gear down even slower since you like to climb like a mountain goat lol. I also followed that your grin front hub and controller have done well.

Yeah we have to see some of these in action, hopefully mammalian and you (LR) get them goin soon!

My bike will be on the road and trails as soon as I get the rear wheel laced. I also have an 18 FET PowerVelocity sinusoidal controller due here any day.

LightningRods said:

25kW continuous, but yeah 25kW out of 14 lbs is better than an Astro Flight 322O's 6kW out of 4 lbs.

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I get 14kw peak, 8kw continuous out of a 4 pound 3220.

That big motor is more power per dollar though. Oh, you need a controller that is capable of running that big motor too.......

did I miss something?

It seems bicycle components are to be given up on completely now.

25-45kw if it were possible on the rest of the bike would rip your tube valve straight off.

I don't trust anyone who tells me otherwise without frequent videos of it being done for a year of riding.

It looks like you are going into MC territory.

recumpence said:

I get 14kw peak, 8kw continuous out of a 4 pound 3220.

That big motor is more power per dollar though. Oh, you need a controller that is capable of running that big motor too.......

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The 3220 is a mighty mite, no doubt about it.

The PowerVelocity controller I have coming is rated at 80 battery amps, 200 phase amps. It should keep the big block well fed. I have a temp sender installed to see the big motor copes.

Hub, rim and tire in at the lacing shop. It will be about a week to special order spokes and then I can get rolling.

LightningRods said:

recumpence said:

I get 14kw peak, 8kw continuous out of a 4 pound 3220.

That big motor is more power per dollar though. Oh, you need a controller that is capable of running that big motor too.......

Click to expand...

The 3220 is a mighty mite, no doubt about it.

The PowerVelocity controller I have coming is rated at 80 battery amps, 200 phase amps. It should keep the big block well fed. I have a temp sender installed to see the big motor copes.

Hub, rim and tire in at the lacing shop. It will be about a week to special order spokes and then I can get rolling.

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I was talking about the big motor pictured earlier. That is a sensorless motor. Kind of a tough motor to find a controller for.

They'll make them for me with hall sensors in them.

Hey LR, what do you think of an azonic 12mm DH hub for 9spd, motor, and brake in the same config you have?


Everything fits perfect in my Q76 knockoff's dropouts. Slap an <50t #35 sprocket against the original 6-hole brake mount. Then just space a 203 rotor off that (possibly with one of those 6 hole threaded freewheel/brake adapters), and bolt both up.

Looks like >50t drive sprocket would hit the brake caliper though. Also looks like it wouldn't be possible to space the rotor far enough over for it's caliper to miss the >50t sprocket, but the bright side is it has 9spd casstte, fits in standard 155mm d/o, is a fairly common stock item, and the rim shouldn't need dished!
It'd just be limited to regen only or smaller diameter sprockets than 50t #35.

I didn't have a 203mm handy for the pics but hopefully you get the idea.





Do you think the hollow alloy axle shaft would hold up?

I really wish this would work. You're correct, the big problem is the space required between the rotor and the sprocket for the brake caliper. The other issue is that there is a tiny window for the motor driver sprocket to line up with the hub driven sprocket. If you look closely at the photos of my swingarm drive the motor is offset to the right. I also had to flip the driver sprocket over to move the teeth even further to the right. I'll be happy to supply you with some offset dimensions to see if you can make this work.

Matt has a lot of experience with using the Top Hat sprocket mount on regular disc brake hubs. If he's still watching this thread maybe he will share some of his expertise with us.

My axles are solid 414O chrome moly. I like that a lot better than hollow alloy. Even without the stress from the power of the motor the Qulbix loaded down with batteries is a lot heavier than most bicycles. All you can do is try it and see if it breaks.

An under 5Ot count wheel sprocket is not going to cut it for single stage reduction. I use a 96t with a 12t driver for 8:1 reduction. The 5Ot would be around 4:1 and geared way too high, even for running on flat ground. #219 is far better than #35 for getting a lot of reduction in a small diameter sprocket.

Thanks you're right about 219, and the 'window' for the motor chain. I should be able to mock something up here to test offsets for the 6.8" wide motor (incld shaft) that I wanna use with tyres/hub.

I ran calcs for 14/50 (3.57) reduction. It would work ok with bht but I think the bigger motor has almost twice the kV. I'm thinking I want a good balance of volts and amps- the motors might not like 12s and >200a (to hit targets of 9-10kw and 40-50mph) I'm guessing? Time to look at #219!

There'd be alot of forward tension/force on the axle as well with all the torque I assume. At least it should be an inexpensive part to make or have made. Or maybe someone has appropriate stock threaded or ready to thread?

LightningRods said:

I really wish this would work. You're correct, the big problem is the space required between the rotor and the sprocket for the brake caliper. The other issue is that there is a tiny window for the motor driver sprocket to line up with the hub driven sprocket. If you look closely at the photos of my swingarm drive the motor is offset to the right. I also had to flip the driver sprocket over to move the teeth even further to the right. I'll be happy to supply you with some offset dimensions to see if you can make this work.

Matt has a lot of experience with using the Top Hat sprocket mount on regular disc brake hubs. If he's still watching this thread maybe he will share some of his expertise with us.

My axles are solid 414O chrome moly. I like that a lot better than hollow alloy. Even without the stress from the power of the motor the Qulbix loaded down with batteries is a lot heavier than most bicycles. All you can do is try it and see if it breaks.

An under 5Ot count wheel sprocket is not going to cut it for single stage reduction. I use a 96t with a 12t driver for 8:1 reduction. The 5Ot would be around 4:1 and geared way too high, even for running on flat ground. #219 is far better than #35 for getting a lot of reduction in a small diameter sprocket.

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You need 3/4 inch between the left side sprocket and the rotor to make everything work. I prefer bmx chain on the left side because it is narrower than 219. 219 has some specific benefits and bmx chain has some benefits.

I second that number. I allowed .75O" between sprocket and rotor and the chain just clears the caliper's hydraulic line fitting. King Sales lists the Top Hat offsets at .125" and .250". I'm not sure how that translates into .750" overall unless the thickness of the adapter is added to the offset.

Matt, your drives are multiple stage so you're most of the way to the reduction you want by the final stage. BMX chain or any 1/2" pitch chain is going to be 15.28" in diameter for a 96T sprocket compared to 9.26" for #219. I need to do it in one stage here so I feel #219 is my best option. 219 chain is a bit wider but there is room for the width.

My machinist is hot to make these hubs but would need to make a run of them to get the price down to reasonable. I have the design work done. It fits perfectly, at least in the 165mm version.

LightningRods said:

I second that number. I allowed .75O" between sprocket and rotor and the chain just clears the caliper's hydraulic line fitting. King Sales lists the Top Hat offsets at .125" and .250". I'm not sure how that translates into .750" overall unless the thickness of the adapter is added to the offset.

Matt, your drives are multiple stage so you're most of the way to the reduction you want by the final stage. BMX chain or any 1/2" pitch chain is going to be 15.28" in diameter for a 96T sprocket compared to 9.26" for #219. I need to do it in one stage here so I feel #219 is my best option. 219 chain is a bit wider but there is room for the width.

My machinist is hot to make these hubs but would need to make a run of them to get the price down to reasonable. I have the design work done. It fits perfectly, at least in the 165mm version.

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Yes. The deepest reduction that is easily achieved with bmx sprockets is 13 tooth freewheel to 60 tooth rear chainring. I can achieve 7 to 1 ratio on the primary belt reduction as well. That gives me 30 mph top speed on a 26 inch tire at 13,000 motor RPM.

Apologies for the slightly OT-ness, but with the Top Hat, how do you deal with the rotor shift towards the frame when you insert the adapter between the hub and the rotor? I imagine you guys can fabricate a caliper mount that can deal with the rotor moving over however thick the adapter is - is that the go to method of dealing with the new rotor position, or does somebody make a shifted caliper adapter?

Thanks.