Front hub install

tattoo400

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USA
So I want to install a front hub on an old MTB I have but am wondering if I can just not install the PAS all together. I want just the throttle to function. Is this possible? instead of disconnecting the PAS, what if it is just not installed? TIA
 
So I want to install a front hub on an old MTB I have but am wondering if I can just not install the PAS all together. I want just the throttle to function. Is this possible? instead of disconnecting the PAS, what if it is just not installed? TIA
Sure you can not install the PAS or eliminate it by moving the hall sensor too far from the magnets. That way you can reconnect it if you want, easily.
Careful about front mount mortors, they can ruin the front fork (and your day) and or throw the rider under certain conditions (also ruining your day).
 
You may have to plug in the PAS sensor and tie it off somewhere safe. Most controllers error out if the sensors they are programmed to accept are not plugged in.
 
You may have to plug in the PAS sensor and tie it off somewhere safe. Most controllers error out if the sensors they are programmed to accept are not plugged in.
KT controllers don't need the PAS connected for the throttle to work.
 
KT controllers don't need the PAS connected for the throttle to work.
That's good to hear, I assumed as much, the bike I will use needs a new fork so what model would best suit my needs? It's old so it retains the cantilever V brakes and I'd like to have a suspension fork. Would any old rock shox set up do? I don't plan to go bigger than a 750w and know its more power than I am used to and being on the front to be extra weary of riding conditions . I thank you for your help...
 
750w and know its more power than I am used to and being on the front
Don't do it ! the front fork is already weak with a small motor, you put a 750w up front and it's only a matter of time before your front wheel leaves you behind.
will use needs a new fork so what model would best suit my needs?
Best to stick with the same make and model of fork as the original.
 
Meaning the fork itself will bend/snap from the torque of the motor? If so, wow. If not, the original fork was replaced with a Marzocchi xc fork but its seals are gone. Your saying a rear hub is best if I want 750w? I have a 350w vivi thats way slow going up hills and i weigh 120lbs. I wanna build this for next summer so theres time to plan it out. The frame/brakes/suspension is a 1991 GT Karakoram, The goal- to go full throttle up hills (around 5 long semi steep on dirt road) for 20 miles and still have at least 25% batt life left...speeds to not exceed 28mph. I'm thinking a Bafang or equivalent 750w 48v 17-20ah battery combo...
 
So I want to install a front hub on an old MTB I have but am wondering if I can just not install the PAS all together. I want just the throttle to function. Is this possible? instead of disconnecting the PAS, what if it is just not installed? TIA
Sure. It’s done all the time.
if it’s a steel fork, test with a magnet and use a pair of Grin, eBikes.ca This is common and quite acceptable.

there are souls braver than I using aluminum forks and these tor arms. X2

Buy from Amazon. Shipping has gotten outrageously expensive from Grin.

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This is common and quite acceptable.
My advise is listen to ppl on this thread. They are way way more technically orientated.
 
Meaning the fork itself will bend/snap from the torque of the motor? If so, wow. If not, the original fork was replaced with a Marzocchi xc fork but its seals are gone. Your saying a rear hub is best if I want 750w? I have a 350w vivi thats way slow going up hills and i weigh 120lbs. I wanna build this for next summer so theres time to plan it out. The frame/brakes/suspension is a 1991 GT Karakoram, The goal- to go full throttle up hills (around 5 long semi steep on dirt road) for 20 miles and still have at least 25% batt life left...speeds to not exceed 28mph. I'm thinking a Bafang or equivalent 750w 48v 17-20ah battery combo...
My advise is listen to ppl on this thread. They are way way more technically orientated.


Regardless of what questionable advice from some here say, why take unnecessary risk?
It's only slightly easier to install a front than a rear, plus the handling is notorious on front applications especially with a 750w. Read through some of the post on the supplied link.
Beware there are a lot of trolls on EBR, they don't care about your safety, they just want to argue.

Here is a good post:

"Re: Disadvantages of front wheel drive for ebike?



by dogman dan » Mar 24 2019 8:02am


First of all, if your bike has 7 or 8 gears in back, it is not in any way easier to do a front hub, vs a rear.

Because of much better traction when the power is in back, in almost every case a rear motor is better. And if you have an aluminum shock fork in front, it gets very technical to make a hub motor work safely. Some shock forks can be used, but they lock up and become rigid when the motor is pulling.

But there are exceptions, which make a front wheel just about the only way. The typical adult trike is the biggest user of front hubs. They have rear drive trains and axles that usually make using a rear motor impossible, or at least a need a welder type situation.

Beach cruisers with a coaster brake, have no brakes at all if you change the rear wheel to a motor wheel. Those can usually be adapted to have other brakes fairly easy though. Might take a welder to do a nice conversion to disk.

Others just have internal gear shifter hubs, and want to keep that, because they loathe derailleurs.

And lastly, the really exotic bikes, belt drive, shaft drive, and so forth, can never use a different rear wheel.


Other type beach cruisers can be a good ride with a front motor, when they are the type with a 7 speed rear gear and rim brakes. They are the one type bike that tends to have a very strong front fork. And you won't be riding it much in dirt, so the traction situation is not a big problem. The only two bikes I'd really recomend a front motor for, are the schwinn trikes and the 7 speed cruisers.


FWIW, I rode about 5000 miles on front hubs, and my main reason was wanting to keep my rear gears on that particular bike. I even built a 50 mph, very high power front hub racing bike. It was fun to learn to power slide the front wheel, and extremely dangerous. But today, all my front hubs gather dust, everything I have runs a rear hub."
 
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interesting, two readers two different conclusions. What’s your experience?

by d8veh » Mar 21 2019 5:05am

Always fit the motor in the back wheel if you can. A front motor looks simpler and if done properly, it can work quite well, but if not done properly, it can be very dangerous and expensive.

As a general rule, front motors should only be fitted in steel forks, except that low power ones are OK in aluminium forks as long as the drop-outs have some meat around them, and I'd always fit at least one torque arm.

by spinningmagnets » Mar 21 2019 10:44am

Most forks really aren't set up to handle high-powered hubmotors, so any front hub would need to be on the lower-powered end of the scale. Of course, some forks are stronger than others. I would suggest that it's a given that you should have a strong torque-arm. If using 1,000W or less, a strong fork (steel) coupled with a strong torque-arm might allow using just one. Sometimes a cheap torque-arm and a strong one "look" similar, but their strength can vary widely, so...always get a good one.

Dogman only scuttles a front drive as dangerous when he created a 50mph version.

You’re cherry picking.

So there’s 3 of the best of ES all accepting a front motor with proper parameters. Nep a friend is a purist on many levels. In his environment his stated negatives COULD be an issue. Lots of kitted bikes are running front motors and spinout isn’t a problem. My winter bike has been a stunned tire front 750W MXUS with a Lyen controller and CA3. A pair of Grin front torque arms and at least 4500 miles. I also 100 lbs of tools hauled between home shop and buddies mega huge shop.

Front drive on ice and snow with Soumi studs is a real tractor at low speeds. SuomiTyres studs will keep you going.
 
interesting, two readers two different conclusions. What’s your experience?

by d8veh » Mar 21 2019 5:05am

Always fit the motor in the back wheel if you can. A front motor looks simpler and if done properly, it can work quite well, but if not done properly, it can be very dangerous and expensive.

As a general rule, front motors should only be fitted in steel forks, except that low power ones are OK in aluminium forks as long as the drop-outs have some meat around them, and I'd always fit at least one torque arm.

by spinningmagnets » Mar 21 2019 10:44am

Most forks really aren't set up to handle high-powered hubmotors, so any front hub would need to be on the lower-powered end of the scale. Of course, some forks are stronger than others. I would suggest that it's a given that you should have a strong torque-arm. If using 1,000W or less, a strong fork (steel) coupled with a strong torque-arm might allow using just one. Sometimes a cheap torque-arm and a strong one "look" similar, but their strength can vary widely, so...always get a good one.

Dogman only scuttles a front drive as dangerous when he created a 50mph version.

You’re cherry picking.

So there’s 3 of the best of ES all accepting a front motor with proper parameters. Nep a friend is a purist on many levels. In his environment his stated negatives COULD be an issue. Lots of kitted bikes are running front motors and spinout isn’t a problem. My winter bike has been a stunned tire front 750W MXUS with a Lyen controller and CA3. A pair of Grin front torque arms and at least 4500 miles. I also 100 lbs of tools hauled between home shop and buddies mega huge shop.

Front drive on ice and snow with Soumi studs is a real tractor at low speeds. SuomiTyres studs will keep you going.
Reminds me of the guy who used open end wrenches hose clamped to the fork as torque arms , he had it all figured out, he even used two for added safety on the front fork weakness.
What he failed to realize is that one of the wrenches wont resists spinning out, because the torque is in the direction of the bolt thread.
Even though there are ppl using front motors doesn't mean they are safe.
If everyone jumps off a bridge....?
Like I already said it's only slightly more work to install a rear hub but vastly safer.
No valid argument against that fact.
 
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