Opinions on front wheel hub systems

[Tom on 101]

I'm riding a front wheel conversion kit that I'm very satisfied with. It's a 36 volt Hill Topper (Clean Republic) on a Marin single speed. I'd like to hear opinions from others who are using front wheel drive systems or changed from that to another system. I don't plan on switching but I'm curious to know what other people have experienced.

What I like is the overall low weight and simplicity of the bike with this kit. The performance matches my expectation and I'm sure I don't need more speed on my build. But it's always good to hear other opinions.

 

[motomech]

They work fine with low-powered system like the one on your geared mini.
As the power aproachs or exceeds 1000 Watts, frt. mounted motors can get rather "squirrely".

 

[ScooterMan101]

How do front hub motors ( up to 600-750 watt ) work when going up steep grade , mountains, with loose/medium pack dirt , twisty single track , slow speed trails ?

I do want to know , since I would like to ride dirt single track trails again .

 

[dogman dan]

For dirt single track, only one reason a sane person would have a front motor.

It's the second motor.

Otherwise, you must have rear motor to ride dirt well. Way too much wheel spin with a front, particularly in sand, gravel on hard pack, let alone the mud ride.

FWIW,, I don't speak from untested bias. I commuted for 5 years with front motors. Most of that with a shock fork, which is always problematic. Fine on street, provided you don't need to curb hop. With a tiny motor, you can even still curb hop ok, just takes more pull on the bars. Pretty much impossible to curb hop though, with the heavier motors. I also may be one of the few people on earth that ran 50 mph with only a front hub. That was wild, learning to drift a powered up front hub on asphalt was quite challenging. Can't recommend it. Once through a corner, it went like a scalded cat though.

So even though I liked a front motor a lot in some situations,,, I still say now that front motors are for street bikes that cannot use a rear motor. Coaster brake bikes, adult trikes, bikes with an IGH. that sort of thing.

And that Marin single speed bike, likely it qualifies. Most single speeds have a narrow rear axle, so you'd have problems running a rear on that bike. But if you have a mountain bike, and want to ride dirt, then you want a rear motor for sure.

 

[Tom on 101]

Thank you guys, that's great info. I'm trying to form my opinions and I agree the front wheel is a bit squirly at speed on loose surfaces. One thing I've noticed is there is an ever growing range of electric cycling approaches. Looks like a rule of thumb might be, if you want the most power and want to do some dirt riding one should consider rear drive or mid(?) with the alternative front hub being more suited towards light weight and power efficiency?

Thanks again for posting, really helps my thinking, which as I get older doesn't seem to be getting any sharper.

 

[MadRhino]

My front wheel hubs are DT Swiss 440 or Sun Ringlé, and the motor is on the rear.

 

[friendly1uk]

One of mine is fwd. It's a loaner. I don't like it. It spins a bit with every pedal stroke. That's just not that safe. In the rain I would end up falling off, I have no doubt. It's an easy conversion to make so the very cheapest of bikes are done that way, but I wouldn't get involved again.

 

[dilkes]

My experience and opinion. I have 2 bikes.

1. A cruiser style bike with 700C wheels and a 3 speed IGH
- front wheel geared kit at 500 watts and 48V, throttle only
- I chose a "slow wind" 201 RPM motor - has higher torque but slower top speed
- Moving my bike (and 250 lb rider), I get about 30 Km/hr which is fine for commuting around the city
- Very pleased with this setup

2. A fat bike with a 750 watt Mid-drive BBS02 at 48V
- both pedelec and throttle
- lots more power, especially climbing hills
- max speed of around 48 Km/hr, lots of torque in low gears
- a powerful bike and lots of fun

So, I think a front geared works well for "tamer" applications. Not sure I personally would do the Hilltopper as it may be a bit under-powered for me, plus the throttle is either on or off, not variable. I might look at something like the Q100 or Q128 from BMS Battery.

 

[dogman dan]

If I wasn't really clear,, riding a front wheel hub bike in the wet was not really dangerous. Not really worse than a regular bike.

It just meant you couldn't do what I liked doing, coasting into a corner and applying full power about mid corner. You just had to coast the whole corner, and if you wanted some power, pedal it. With rear hub, me at least, pretty comfortable with it if the rear tire powered up starts to drift. I used to go out in the rain on a 750 cc motorcycle, just to get that slide on wet painted crosswalk stripe. (that was 30 years ago)

But make no mistake about it, until the wheel does start to drift, having the front wheel pulling you through the corner, simultaneously pedaling, feels great. 2WD, both tires grabbing traction. Felt great right up to when I started cornering with a 50 mph front hub. Then it started to drift too easy, too touchy to ride it hard.

In dirt, with the right sandy over hard packed surface, learning to drift the front wheel under full power was kind of fun, and prepared me for that bike that would do it on asphalt.

But trail riding, while it could be done, it really did suck with front hub. Firstly, you do need that easy lift of the front wheel in some places. To curb hop a big rock or root. And if you got stopped on a steep bit, then restarting with a front hub was very difficult. You'd spin the tire quite a while to get going again.

With a rear wheel you can wheelie it a bit over the larger obstacles easy. And of course, back on that just right dirt surface, drifting the rear wheel and doing the counter steer thing is just plain fun. Something quite addicting about turning left by pointing the handlebars right. 8)

In the end, dirt or asphalt, it just ends up to be more controllable to power up just the rear wheel. It's easier to do more power, and allows the use of skills you learned riding dirt motorcycles. You can steer with mostly just your ass and the throttle, with the front wheel digging in hard only when you need it to really crank a turn. Touch of front brake, get that front tire digging, start the turn, then finish with ass and throttle.

 

[MadRhino]

My experience and opinion. I have 2 bikes.

1. A cruiser style bike with 700C wheels and a 3 speed IGH
- front wheel geared kit at 500 watts and 48V, throttle only
- I chose a "slow wind" 201 RPM motor - has higher torque but slower top speed
- Moving my bike (and 250 lb rider), I get about 30 Km/hr which is fine for commuting around the city
- Very pleased with this setup

2. A fat bike with a 750 watt Mid-drive BBS02 at 48V
- both pedelec and throttle
- lots more power, especially climbing hills
- max speed of around 48 Km/hr, lots of torque in low gears
- a powerful bike and lots of fun

So, I think a front geared works well for "tamer" applications. Not sure I personally would do the Hilltopper as it may be a bit under-powered for me, plus the throttle is either on or off, not variable. I might look at something like the Q100 or Q128 from BMS Battery.

I use 2 bikes. I have built many but I use 2 of them mostly.

For the street
The fast bike, well above 60 Mph with acceleration to beat motorcycles.
Cromotor, 65mm rims, 24 X 3.0 Berm Master street tires

For the mountain
A slower bike, close to 50 Mph on the flat with a slight rear wind, but able to climb steep repeatedly and crash without damages (most of the time).
X5404 motor, Double Track rims, 26 X 2.7 Nevegal DH tires.

Both bikes are fed 20+ Kw. I would not use a front hub for those applications of course, and a slow ride is not appealing to me.

 

[Tom on 101]

Thanks for the replies!! I hope there is more people willing to post. My own experience is evolving. Yesterday I rode a front hub system about 8 miles on a dirt fire road. I didn't experience any washout, so when we were done I messed around in the parking lot to get it going. Yes the front squirls out but I found it very correctable, after a few minutes of dust it seemed fun to have the power in the front wheel. I think the way I'm using the front hub is pretty good, takes me up the road, then the motor rests as I come down. Gravity provides the thrills and maybe I use some electricity on the way down. I'm just worried I'll break the hub motor on a jump or rut if I get too into it.

 

[davec]

i've been riding fw hub for years thousands of miles- trick as discussed many times on here - is steel fork, and 2 torq arms
also i keep the motor at 1kw and it's fine... i would probably not push it passed that
i dont think i'd ever change my setup - the handing is good- and i dont have to worry about rear wheel issues
the only risk is the front hub locking up which can be dangerous- but with a well maintained hub- it shouldn't be an issue
i ride on pavement only

 

[dogman dan]

Sure, you can ride dirt roads with front hubs. And learn to slide em under power. Fun shit. And you don't need to limit power to 1000w. 3000w front hub is fun, if you are dressed for it when you do lay it down. Play with the front hub, learn from it, become a real wheelman. But in the end, you will gravitate back to rear hub, we all do eventually. Once you have six e bikes, you will find the front hub ones gather dust.

But if you ride serious trail, and can't pull that front wheel over the rocks and roots, yer screwed. And, a bike able to ride that shit, it's not going to have a steel fork. You wanna ruin a $700 fork with a motor spinout?

If you have rock staircases to climb, you sure don't want front hub.

 

[AF7JA]

I have a front hub on my commuter. It os a 350W geared motor that, according to the display, is almost never operated at full power.

It works well for my purpose; but I am not, in any way, going to call it a performance e-bike. As was mentioned, I chose a front motor because my commuter was not suitable for a mid drive. It has a belt drive with an eccentric bottom bracket. The IGH is a NuVinci 360. Overall, it is not something that can easily support anything but a front drive.

One thing I found I like about the front grive is that, combined with pedaling, it has a two wheel drive. This is particularly beneficial on snow, and some ice conditions. I doubt that this would be useful with a high power motor; but with the small motor, throttled lightly, it works well in those conditions.

No, a front motor is not a high power solution; but for a commuter it may work well. It works well in my situation.

 

[2old]

I have a 350w front hub commuter with "dolphin" battery pack. Other nice aspect of "fronties" is nice weight distribution and "seemingly" lower overall weight than rear-oriented systems. Pedals really well on those occasions when I don't use the motor.

 

[dogman dan]

For AF7JA, the bike could not have anything but a front hub. Most of the disadvantages of a front are not apparent at 350w either. But if you feel the need for more power and speed, don't hesitate to power up to as much as 48v 1000w. It's really not that much power to handle up front. Not if you can ride at all.

I'm just saying, front hub is not the first choice. There is no way a geared motor of any size makes the bike handle shitty if it's in back, AND, you are carrying a 10 ah the battery there too.

But for sure, if you can, put the battery up front.

 

[Chalo]

There's one huge advantage to using a hub motor in the front: If you do that, you won't have a hub motor in the rear.

Hub motor wheels are inherently weaker and less reliable than conventional wheels, and they impose unwelcome compromises in the bike's gearing when used on the rear.

Better to have the weak wheel in front, where its job is easier, and where it doesn't curtail your options in terms of gearing range or component quality. Besides, doing it that way results in an all-wheel-drive bike.

 

[Ykick]

I liked my front hub motor bikes using both DD and geared. I’ve gotten away from them and now only use rear motors but Chalo makes a valid observation.

FWIW, I never had any spoke or chain issues running front hubs up to 2kW. Rear is definitely harder on spokes and achieving a good chain line is sometimes harder than stock pedal rear wheel.

Riding in snow front wheel drive gave me more warning on slick surfaces. But my rear motor has never slid enough that I couldn’t recover either.

Only 2 things I actually preferred using rear hub motors: #1 - sometimes ‘like to hop curbs and it’s nice to have the light front wheel. #2 - sometimes I need to walk the bike through a narrow doorway and it’s easier to stand it up and hold that position on the rear wheel applying a little throttle to the rear motor.

 

[Toorbough ULL-Zeveigh]

Hub motor wheels are inherently weaker and less reliable than conventional wheels,

you really should correct that typographical error.
there is nothing inherent about it.

or for go spokes completely, UST mounted directly onto the hub casing (with apropriate flanges).
absolute statements are always absolutey wrong.
but i will defer to mr.rhino or jincr's direct experience should they choose to weigh in.

it's OK to call out stupidity where you find it. No good can come of treating stupid ideas like they have the same value as valid ideas.

 

[dogman dan]

Well, depends on the abuse you put it through, whether or not a rear hub motor wheel is too weak to use, or not.

I taco folded one, once, in a crash like situation. I pretty much jammed the wheel into the corner of a curb. This would have taco folded a regular wheel too, sooo pretty hard to blame it on a rear hub wheel.

Otherwise, with better than the worst spokes and rims china can make, I've ridden some pretty nasty, pretty rocky trails for years with no wheel issues. I do pay some attention, and never ride a wheel with one spoke overtight, and another over loose. I've never bent a rim except that one I taco folded, but if I do bend a rim,,, I'll replace it. I won't overtighten one side, then blame the failure that happens later on it being a rear wheel.

One valid reason to ride front hub just got mentioned. You can leave your rear gears as they were. This particularly applies with a belt drive, or an IGH, but I rode 10,0000 miles commuting for 5 years with front hub, because I wanted to be able to cruise fast. 30 mph is legal in my state, so I wanted that good 11 tooth rear gear.

That need changed, I got sick, could hardly pedal at all for 3 years, and now 6 years later still don't pedal hard. I don't need that high rear gear anymore. 14t is fine, since my bikes tend to have at least a 52 up front.

 

[LewTwo]

Hub motor wheels are inherently weaker and less reliable than conventional wheels, ....

I will grant that hub motors wheels are inherently less reliable as anything more complex is inherently less reliable.
However I would challenge the statement regarding 'inherently weaker' as they generally have larger, heavier flanges and shorter spokes.
Pray tell what you reasoning is to support that statement.

 

[Tom on 101]

Nom nom, Pass the popcorn. This is great stuff!

 

[Chalo]

Hub motor wheels are inherently weaker and less reliable than conventional wheels, ....

I will grant that hub motors wheels are inherently less reliable as anything more complex is inherently less reliable.
However I would challenge the statement regarding 'inherently weaker' as they generally have larger, heavier flanges and shorter spokes.
Pray tell what you reasoning is to support that statement.

Hub motor wheels have less lateral bracing angle than normal wheels, which makes them more flexible and easier to bend or collapse. They don't have to be that way, but they are (so that the hubs can fit a bigger range of rim diameters)

Rear hub motor wheels usually have much more dish (lateral tension difference between one side and the other) than normal rear wheels. This makes them weaker and less stable, in proportion to the degree of tension imbalance.

The insertion angle of hub motor spokes into the rim, even when laced cross-one, tends to be more than optimal for the spoke, and promotes breakage at the threaded end.

Hub motor flanges are often made from steel, poorly finished and thinner than normal aluminum flanges on bicycle hubs, and drilled with holes that are too large, all of which promote breakage at the spoke elbow.

Lastly, thick spokes-- such as those which are pervasively used on hub motor wheels-- make a wheel weaker. Spokes can only work to support a rim when they are in tension; the moment they go slack, they might as well be missing (from a structural standpoint). Thick spokes lack elasticity, so they go slack much sooner and in larger numbers than thin spokes. Also because of the same lack of elasticity, they tend to overload and crack the rim at the holes. This in turn rapidly leads to wheel collapse. Again, they don't have to be that way, but they typically are.

 

[MadRhino]

All this doesn't mean you can't build a good wheel on a hub motor, only that it is much more work to do. That is why so many are willing to endure the weight penalty, to build with motorcycle rims, spokes and tires.

To build lightweight and reliable, you need to invest some time and Art :wink:

 

[LewTwo]

... ....

I can not speak to the issues regard uneven offsets as I build my wheels symmetrically (I use rim brakes and IGH rear hubs).
Most of problems that you refer to are NOT 'inherent' but rather poor design, material and/or build quality.