Is there any reason I should do a front/rear hub road/gravel bike instead of a mid drive road bike or hybrid/mtb

Q128C or AKM128c (same motor) are rated at 500w and can easily handle 48v and 22A. Some people run them at 25A. They give very good torque and good efficiency because they have a high internal reduction ratio. Mine is 10 years old now and is bulletproof. I'd highly recommend one of these motors if you want something in that power range.
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E-HP said:
There was a sale thread on the marketplace forum, but I don’t think it’s active anymore.
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Yea, I looked a while ago, because it seemed well engineered for a friction drive, but it doesn't seem to exist anymore. And with friction drives the devil is really in the details, since you need just the right amount of tire deformation. So one can't just buy something that looks similar and hope it will work.
 
Gruesome said:
Yea, I looked a while ago, because it seemed well engineered for a friction drive, but it doesn't seem to exist anymore. And with friction drives the devil is really in the details, since you need just the right amount of tire deformation. So one can't just buy something that looks similar and hope it will work.
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I remember reading through that thread when I first joined ES and thinking "man that's so cool, that's what DIY ebike stuff is all about". He had that thing dialed in.

Offroad version too.
 
uhmwpolyethylene said:
d8veh said:
d8veh said:
Also, you can't get good traction because of the thin tyres.
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Almost all the Gravel bikes I have seen can take up to 50mm (i.e. 2") wide tires.

In fact, the official spec on the Shimano GRX group is "up to 50mm" wide tires.

And 50mm tires are the most popular size at the biggest gravel bike racing event:

www.cyclingweekly.com

50mm tires, jerseys with built-in hydration pouches and other gravel tech trends at Unbound

Here's a first look at the newest tech trends that we'll be seeing at gravel racing's biggest showdown
www.cyclingweekly.com www.cyclingweekly.com

"According to our conversation with a range of LifeTime Grand Prix riders heading to Unbound with aspirations, 50mm tires were the most frequent answer when it came to the size of treads riders would be running."
 
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So like, rear hub motors , they can be fitted perfectly with a high end drivechain without messing anything up? Are there any "premium" rear hubs that are uh, smoother? My brain is just thinking about wheel groupsets idk. I know bafang hubs are always popular, besides those proprietary euro ones is any other brand higher quality?
 
uhmwpolyethylene said:
So like, rear hub motors , they can be fitted perfectly with a high end drivechain without messing anything up? Are there any "premium" rear hubs that are uh, smoother? My brain is just thinking about wheel groupsets idk. I know bafang hubs are always popular, besides those proprietary euro ones is any other brand higher quality?
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For the gravel bikes and newer road bikes the rear spacing will almost always be 142mm x 12mm thru axle.

The only gravel bikes I have seen with what I think is 135mm are the ones from bikesdirect.com. (Yeah even the cheap steel gravel bikes made by State are 142mm x 12mm thru axle.)

I bring this up because everyone here has recommended a 135mm hub motor but you will have to shop the bike (if wanting gravel or road) carefully if you want to fit these suggested motors.
 
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Gruesome said:
What is 'they'? Initially I thought you meant 50mm wide tires, but then you are saying 'like, rear hub motors', so you are not talking about rear hub motors, but something similar?
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I think he might be referring to the freehub body. For example, Shimano GRX 12 speed rear hub uses microspline freehub body....so in order to adapt that drivetrain to the wheel he would need a hubmotor with microspline.

The only 142mm x 12mm hub motor that I know of that has microspline freehub is Mahle X20. (Grin all axle, although available in 142 x 12mm, does not have microspline as an option.)
 
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ebike4healthandfitness said:
I think he might be referring to the freehub body. For example, Shimano GRX rear hub uses microspline freehub body....so in order to adapt that drivetrain to the wheel he would need a hubmotor with microspline.

The only 142mm x 12mm hub motor that I know of that has microspline freehub is Mahle X20. (Grin all axle, although available in 142 x 12mm, does not have microspline as an option).
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I deleted my post, because I finally got that the 'like' didn't mean 'something like', but was the 'valley like'. Slowly getting used to the local vernacular...
 
ebike4healthandfitness said:
I think he might be referring to the freehub body. For example, Shimano GRX 12 speed rear hub uses microspline freehub body....so in order to adapt that drivetrain to the wheel he would need a hubmotor with microspline.

The only 142mm x 12mm hub motor that I know of that has microspline freehub is Mahle X20. (Grin all axle, although available in 142 x 12mm, does not have microspline as an option.)
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So, does GRX use a different cassette hub ('freehub' ?) than 105 or Ultegra or Deore? Or is the difference between 11 and 12 speed? For some reason (bad reading skills, I guess) I thought the Shimano and SRAM 11 and 12 speed cassettes were all compatible?
 
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Gruesome said:
So, does GRX use a different cassette hub ('freehub' ?) than 105 or Ultegra or Deore? Or is the difference between 11 and 12 speed? For some reason (bad reading skill, I guess) the Shimano and SRAM 11 and 12 speed cassettes were all compatible?
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The single chain ring 12 speed GRX uses micro spline while the dual chainring 12 speed GRX uses the 36.85 mm HG freehub (commonly called the 11 speed road freehub which also takes 12 speed road cassettes....and it is actually the 12 speed road cassettes that the dual chain ring 12 speed GRX uses)

This, in contrast, to the 35mm HG freehub body that is used on the 135mm hub motors. These 35mm freehub will fit up to 11 speed mtn cassettes and up to 10 speed road cassettes. The 11 and 12 speed road cassette drive train needs the longer 36.85mm freehub body.
 
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Mhmm. I thought it was an older 10 speed hub that was 1.85mm wider than my current 105 11 speed hub, and that's why my spare HG700 cassette came with the 1.8(5)mm spacer? Apparently not: Bike Freehub & Cassette Compatibility Manual
Sounds like one has to be super careful when buying a hub drive.

Update: I looked at the (German) Shimano dealer instructions. According to page 8 my bike apparently has an 11 speed mountain bike free hub, since the 1.85mm spacer is NOT needed (it actually does not fit, neither the 11T sprocket nor the lock ring engage with the freehub when the 1.85mm spacer is inserted) . The spacer is needed to mount the HG700 cassette on the 11 speed street freehub.
 
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Gruesome said:
Mhmm. I thought it was an older 10 speed hub that was 1.85mm wider than my current 105 11 speed hub, and that's why my spare HG700 cassette came with the 1.8(5)mm spacer? Apparently not: Bike Freehub & Cassette Compatibility Manual
Sounds like one has to be super careful when buying a hub drive.

Update: I looked at the (German) Shimano dealer instructions. According to page 8 my bike apparently has an 11 speed mountain bike free hub, since the 1.85mm spacer is NOT needed (it actually does not fit, neither the 11T sprocket nor the lock ring engage with the freehub when the 1.85mm spacer is inserted) . The spacer is needed to mount the HG700 cassette on the 11 speed street freehub.
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Yes, you have the 35mm freehub. If you had the 36.85mm freehub you would use the 1.85mm spacer to correctly position the 11 speed Shimano mtn cassette.

P.S. Interesting fact is that despite the 11 speed Shimano mtn cassette and 11 speed Shimano road cassette needing different length freehubs they both have the same cog spacing. This because 11 speed Shimano mtn cassettes are dished in such a way that the larger cogs follow the contour of the spokes eliminating the need for the 1.85mm longer free hub of the 11 speed Shimano road cassette. For this reason 11 speed GRX shifters both use 11 speed Shimano road cassettes and 11 speed Shimano mtn cassettes ---> https://bike.shimano.com/en-US/product/component/grx-11-speed.html
 
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Thanks a lot! So Canyon put an 8-10 speed mountain bike freehub on this bike, with an 11 speed mountain bike cassette. Very odd. So either a 35mm or 36.85mm freehub would allow me to keep my cassette and derailleur, but on the 36.85mm freehub I'd need to use the spacer.
Back to the usual program...
 
Gruesome said:
Canyon put an 8-10 speed mountain bike freehub on this bike, with an 11 speed mountain bike cassette. Very odd.
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Not sure why that article you linked in post #37 calls the 35mm Shimano HG freehub 8 to 10 speed mtn cassette. It is actually 8 to 11 speed mtn cassette (and 8 to 10 speed road cassette).
 
ebike4healthandfitness said:
Not sure why that article you linked in post #37 calls the 35mm Shimano HG freehub 8 to 10 speed mtn cassette. It is actually 8 to 11 speed mtn cassette (and 8 to 10 speed road cassette).
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I have not the slightest idea. I haven't run into any real contradictions yet, but the names different people use might indeed be different. I could imagine that Shimano initially introduced that freehub as the 8 speed hub, because 9, 10 and 11 speed did not exist yet. And maybe later they renamed it to 8 - 10 speed freehub, and then maybe even later to 8 - 11? Or maybe they never renamed it, or didn't even name it the 8 speed hub.
 
Gruesome said:
I have not the slightest idea. I haven't run into any real contradictions yet, but the names different people use might indeed be different. I could imagine that Shimano initially introduced that freehub as the 8 speed hub, because 9, 10 and 11 speed did not exist yet. And maybe later they renamed it to 8 - 10 speed freehub, and then maybe even later to 8 - 11? Or maybe they never renamed it, or didn't even name it the 8 speed hub.
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FWIW, Here is a Shimano Deore 135mm 11 speed mtn hub:


It is listed as 8/9/10/11 speed in the specs.
 
uhmwpolyethylene said:
Unrelated question, for those of you who commute and tour on trails; tubeless latex or Schwalbe Marathon plus ? I wasn't aware the latex acts like super slime, and unsure of the Weight between the two, but the rolling resistance of Mplus, the most reliable Schwalbe, is really poor. I have however met a guy who did multiple tours across America, probably on road, who only changed his flats on Mplus once per 3 months.
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I can speak from experience with the Marathon plus. Not on an ebike, just a road bike, rolling resistance isn't bad at all but they are heavy for road tyres (obviously an aggressive tread version would roll worse). I've used them for 12 years ish and have NEVER had a puncture. I've ridden over glass, nails, screws, flint, glass bottles which burst under my tyres....nothing. I've stopped carrying a CO2 inflator, levers and patches because they are bulletproof. Just make sure you keep the pressure up, they can pinch flat like anything else. In my opinion, the extra weight is well worth the lack of hassle and worry about punctures. I recommend them to everyone.
 
Question here, been following this guy with a cool 5000w 5lb drone motor to rear setup bike, and so, he's selling a commuter battery that I guess puts out a good power draw at 36v plus higher current with much more efficiency with like 3000w max vs 3800 or something for his 52v . What's up with that? I thought higher voltages were more efficient? In a hub motor or mid drive will 36v and high current put out anything above 250w or 500w?
 

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You can have an extremely efficient motor at any voltage if you put the effort in to size the current paths large enough so that resistance doesn't get in the way.

At a certain point it makes no sense to increase voltage because the current paths just get too heavy/big.
 
None of the numbers in that table relate to the motor's efficiency. The speed at which the motor is most efficient will be unique to that motor, so choosing a scenario that's most efficient for one won't be efficient for the other and vice versa, so for the purposes of determining which is more efficient, the table has no value. In addition, motor efficiency and range are not the same thing.
 
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