Geared Hub with Off-Road use...who's done it?

[unclejemima]

How many guys (and gals) have used a geared hub off road. I heard DD's are the hub of choice for ultimate reliability, but I'm curious to see who's used the lighter geared units. How well have they held up? Clutch, planetary gears, etc.

I'm looking to see how well these units hold up off-road. List your make/model, power, hard/soft tail and approx mileage.

Thanks for the info!

 

[biohazardman]

I have a BMC V2s @66V that has 6K on it. It is not stock as I have beefed up the phase wires. I put about 6K on it and expect 100-200 miles were on trails. I was not thrashing it off road though usually on hard packed roads/paths or gravel and no steep terain. I did move right along 30+ on the smoothest parts of the roads though. Examples/vids of some rides in the links in my sig. The motor has recently had problems and needs some werq on the halls. The gears were replaced with the newer units early on as I thought it had problems. Probly didn't though.
and another link to a BMC on the trails http://endless-sphere.com/forums/viewtopic.php?f=6&t=12654

 

[motomech]

I was working on a very small island in the West Indies and used to do light trail riding on a MTB with as MXUS geared mini-motor installed up front.
Actually, it was more like trials riding, just puttering around. Sandy trails, some flat rock climbing, no jumping or slamming into berms, etc.
With a low power motor[700 to 800 Watts] and low speeds, one gets a sense of when the gears are getting stressed by the sound and feel of the motor.
The rule of thumb being, if a geared motor ever looses traction[in the mud or on a slight drop-off], always get off the power before it hooks up again.
Of course a frt. mounted mini-motor is never going to be a serious off-road machine. Any kind of uphill with poor traction will have the tire spinning.
But it was fun and successful enough to make me want to try a dual mini-motor set-up for off-road duty.
My most recent conversion, a 2WD road bike with high speed mini's has further reinforced the idea and I'm getting ready to order a pair of low speed mini's for off-road use.
The street bike, even with semi-slick tires is a great climber with excellent throttle control, motoring right up wet grassy hills.
I figure that splitting the load between wheels will give the gears a better chance of survival, along with the advantages of better traction, balance[weight distribution], less stress on the drop-outs, etc.
If I was going to try a single off-road geared motor, it would not doubt be the MAC, with it's lower cost and parts availability.
If I was going to try to build a serious off-roader, I would use a pair of MAC 350's for 2WD.

 

[dogman dan]

Like everything, it depends. I guess I have fairly tough trails, too many really steep spots, nice and rocky. I've melted down a Heinzmann gearmotor, an Aotema dd motor, and a couple 9 continent dd motors riding them. Gotten some others almost to the melt point many times. For me, it's overheating that's the real problem. Lots of bogging down the motors too much going up the hills followed by melty motors.

At this point my favorite motos is a very slow winding of the 9c dd motors. But I haven't tried a very slow winding Mac. I bet one of those would do fine too. I've learned to stop trying to ride more than about 8 miles per session too, which helps.

So as I said, it depends. Any hubmotor will work pretty decent if the grades are mild, and any hubmotor can be melted if the grades are extreme. I don't know about hucking jumps, I don't like going over the bars much faster than 20 mph. So riding at 15-20 mph most of the time, I don't leave the ground much.

At one point, I was convinced a dual hub gearmotor bike would be the cat's meow. Maybe it would, but I came to like having the ability to wheelie over the bigger rocks, avoiding yet another trip over the handlebars. So now I don't much want to make the front wheel heavy. Using slow enough windings and shortening the ride has more or less solved my problems. I run about 1500 watts minimum, and in winter run 3000.

 

[unclejemima]

Thanks guys.

Does BMC build a MAC 350's equivilant?

I'd love to run a 2wd mini-geared motor off-road, with perhaps 600W at either end.

How light can you get these geared motors?

I have old school Rock Shox Judy XL forks up front. They have an aluminum drop-out. I would imagine this would be a no-no with even a light hub? I've heard the aluminum forks and ANY hub motor equals a broken fork?

 

[Phoebus]

I use BMC motors exclusively for my off road riding. The terrain is extremely rocky and rough. I ride the BMCs on jumps and drops (up to 5 feet). I do not shy away from anything, in fact I seek out the roughest conditions possible and do not even think about taking lighter for the sake of my motor.

I have gone through one clutch, but the terrain wasn't to blame - I lugged the engine too much, and wore it out. My second clutch, now without lugging it, has shown no sign of wear (though it is still new).

Highly recommend using geared motors for off road - IF you have full suspension. I suspect that my 8" of rear travel helps to cushion the shock of my riding.

 

[motomech]

Thanks guys.

Does BMC build a MAC 350's equivilant?

I'd love to run a 2wd mini-geared motor off-road, with perhaps 600W at either end.

How light can you get these geared motors?

I have old school Rock Shox Judy XL forks up front. They have an aluminum drop-out. I would imagine this would be a no-no with even a light hub? I've heard the aluminum forks and ANY hub motor equals a broken fork?

Does BMC build a MAC 350's equivilant?

I don't think so. What's wrong with the Mac 350? Actually, it's a larger geared motor that is narrower and about a pound lighter than the regular Mac.

I'd love to run a 2wd mini-geared motor off-road, with perhaps 600W at either end.

That would be about the minimin in power. I run 600W + 600W on my street bike and it doesn't have the power to tackle a good off-road climb.

How light can you get these geared motors?

The Ananda Q100's that I'm running now are about the lightest practical mini at 2.3 Kg.. They can take, maybe 700 to 800 Watts. The MXUS[see Cell_man's site]is larger in diameter[160 mm], weighs 3 Kg. and is good to 1000 Watts or more. The Mac 350 weighs 4.3 Kg.

I have old school Rock Shox Judy XL forks up front. They have an aluminum drop-out. I would imagine this would be a no-no with even a light hub? I've heard the aluminum forks and ANY hub motor equals a broken fork?

Not necessarily. Lots of us have frt. mounted motors, but it requires the right fork and careful fittment.
Click on my build link for pics of frt mounted mini;s.

Sounds like it's time for you to dig in and start reading. Lord knows there is enough here on the subject. You can't use the obtuse search engine here with the term 2WD, but you can Google it and be redirected back to the site.
The subject of 2WD always stirs up the pot here. To some, the idea is almost un-American. To me, it seems natural. You will find some dogma[not to be confused with Dogman :wink: ]and you will find wisedom[like anything, I guess].

Here is one of my Fav.s;
Quest For Super Stealth, by Chinaphil;

http://endless-sphere.com/forums/viewtopic.php?f=3&t=24866&hilit=quest+for+super+stealth

I would think Lipo would be a must to keep the overall weight down mon a semi-serious dirt Ebike

 

[motomech]

I use BMC motors exclusively for my off road riding. The terrain is extremely rocky and rough. I ride the BMCs on jumps and drops (up to 5 feet). I do not shy away from anything, in fact I seek out the roughest conditions possible and do not even think about taking lighter for the sake of my motor.

I have gone through one clutch, but the terrain wasn't to blame - I lugged the engine too much, and wore it out. My second clutch, now without lugging it, has shown no sign of wear (though it is still new).

Highly recommend using geared motors for off road - IF you have full suspension. I suspect that my 8" of rear travel helps to cushion the shock of my riding.

Sounds like a hoot!
When are you going to post some pics? I looked, but didn't see any.

 

[Phoebus]

I won't, I'm afraid. My bike is built for stealth, so no photos of it are allowed : (

 

[unclejemima]

I use BMC motors exclusively for my off road riding.

What motor? The V2?

I have gone through one clutch, but the terrain wasn't to blame - I lugged the engine too much, and wore it out. My second clutch, now without lugging it, has shown no sign of wear (though it is still new).

How many miles did you put on it before you wore the clutch out? No planetary gear replacements? Any maintenance (have you ever had to pull the hub apart?

Highly recommend using geared motors for off road - IF you have full suspension. I suspect that my 8" of rear travel helps to cushion the shock of my riding.

I don't have full suspension...so perhaps I should not go with the geared...

Hoping to find someone who has run a hardtail off-road with a geared hub...?

 

[unclejemima]

Could you run a larger motor in the rear and a smaller one in the front for a 2wd bike, or would both have to be the same size?

 

[Phoebus]

The V2T, yes.

Planetary gear was in near pristine condition when I replaced the clutch.

I had something like 250mi on the motor when I replaced the clutch. That's 100% extremely rocky trail riding. I expect my new clutch to last much longer, as I now know how not to damage the clutch (avoid lugging, basically).

To be clear, I damaged the clutch by misuse, not by riding on rough terrain. I wasn't aware that lugging the motor could kill the clutch, and I did exactly this to the extreme.

 

[mr.electric]

I think the clutch and gears get hammered if you let the wheel spin up in the air then touch down. No throttle when the drive wheel is off the ground may help extend the internals life a bit.

 

[motomech]

Could you run a larger motor in the rear and a smaller one in the front for a 2wd bike, or would both have to be the same size?

Yes you can.

 

[motomech]

I use BMC motors exclusively for my off road riding.

What motor? The V2?

I have gone through one clutch, but the terrain wasn't to blame - I lugged the engine too much, and wore it out. My second clutch, now without lugging it, has shown no sign of wear (though it is still new).

How many miles did you put on it before you wore the clutch out? No planetary gear replacements? Any maintenance (have you ever had to pull the hub apart?

Highly recommend using geared motors for off road - IF you have full suspension. I suspect that my 8" of rear travel helps to cushion the shock of my riding.

I don't have full suspension...so perhaps I should not go with the geared...

Hoping to find someone who has run a hardtail off-road with a geared hub...?

I don't have full suspension...so perhaps I should not go with the geared...

Then you need to get a FS bike.
If you can't or don't believe me, then get the slowest wind Mac[T12]and run it on 48V.
You won't be able or want to go fast without rear suspension.

 

[motomech]

I won't, I'm afraid. My bike is built for stealth, so no photos of it are allowed : (

Oh, I get it, you didn't finish making the payments on it.

 

[Kurt]

I guess having no suspension is tough on a motor and I run my little geared hub at 45a 60v ..2700w in a 20" wheel. Its at the rear of a recumbent trike and I have been doing a lot of dirt tracks and rough roads. It gets a beating in the city to with gutter hops and going down stair cases .

even just around my back yard I am always doing silly little jumps and racing up over and down mounds - over rocks.

video of me being silly in my front yard...slope is way steeper than it looks.

[youtube]lkhhNcc-Lag[/youtube]

Kurt

 

[waynebergman]

Day one with my new Mac 10t. So far I really like its ability to climb. I am not running high power so I don't expect it to perform like a dirt bike but it is doing what I had hoped for......... Quiet, smooth, light weight, no drag when coasting or pedaling and reasonably priced. So far I think its a winner for my application which is cruising the back roads at 20+mph and also climbing some nice single track in beautiful peace and quiet. WIN WIN IN MY BOOKS!

 

[kfong]

For single track, my favorite motor is the BMC v2t. No experience with Macs. The newer gears and clutch are holding up compared to the first generation stuff. I abuse my motor in the trails and have had no issues with it after 3 seasons of trail riding. I look for jumps and log piles. I've had many crashes and climbs that bog down the motor. I'm usually pedaling in the trails and I do let up on the throttle after a jump. My trail rides can last up to 30+ miles with only stops to hydrate. My average is usually 20-25 miles and it has been reliable in 90+ deg. I'm running 12s lipos and current limited to 35amps. Most riders who damage the BMC motors are usually pushing too much watts through them.

 

[Phoebus]

Just to be clear, I was abusing my motor by lugging it up stuff without pedaling. I no longer do this, and expect my motor to last a long, long time. My gears were in pristine condition - looked literally brand new - when I pulled the assembly for clutch replacement. All of this is with extremely rough riding, with jumps, drops, etc.

 

[alfantastic]

Been running a MAC 10T at 52v 30A, on fairly rough tracks for about 300 miles.
My view is that it is a tough little bugger, although haven't run it long enough to determine reliability.
The battery's in the frame, and the weight of the front forks balance out the rear hub beautifully.
I wouldn't recommend doing jumps or mega rough stuff, as others have said, it'll probably trash the clutch.
Save up for a Haibike or KTM if you wanna go down this route.

 

[-Bugsy-]

I have a BMC V3 on an Intense M6. 12S LiPo 20 Ah, 50Amp max on the controller.

Have been quite impressed with the (ahem) punishment that it has tollerated.

This bike is used almost exclusively offroad and frequetly in the mud to the point of complete immersion. The rear wheel is regularly off the ground (not landing under power though). Jumps with transitions and hucks to flat. Fast across rough ground inc rock gardens all fine. The most damage that has occurred is the axle of the motor eating out a bit of the aluminium dropout - still fine, just noticable.

Saying all that, i'm also pretty big on maintainence. stripdown / clean / lube / rebuild combine with the 9" rear wheel travel of the M6 has allowed me to get away with this E-Abuse of a geared hub.

Note - After finally burning out the BMC V3, I replaced it with a torque version BMC V2T. Notice a slower top speed, but far sharper punch off the mark and out of tight single-track corners. This motor seems less tollerant to my riding style. Can hear gears grinding as soon as rear wheel lifts off ground. Yet to pull down motor and have a look at config of planetry gears

In short - IMO - Long travel rear suspension allows you to get away with more on what is considered a 'fragile' road going hub motor.

 

[kfong]

I would be courios why you only get noise while the wheel is off the ground. I'm thinking that is a problem with the clutch while freewheeling.

The only noise I get when pushing hard is the cogging noise as the motor tries to keep in sync during a climb where I am in the wrong gear and not able to help. This noise quickly goes away when not bogged down. As long as you are not running high power or doing a really long climb without helping the motor, this motor is quite durable in the trails and has yet to let me down. I've had to replace a couple of spokes, several inner tubes and tires along the way. The cogging noise isn't an issue. If you have broken gears, I would imagine the noise from that would be continous.