Cheap ebike for electric conversion

[CUDAcores89]

SO I Decided I want to build an ebike...

A couple of details about myself:
I am a teenager and therefore am on a budget. Currently I drive about 4 miles to get to my job where I work. After realizing how much cheaper it would be to own a bike instead of a car to get places, I was all ears.

I did my research. I built a 1KWh battery out of 18650 cells and I bought a front hub motor conversion kit from ebay (which worked surprisingly well for the few seconds I was able to use it). I then went to a thrift store and picked up a used bike for 50 bucks. After building the battery, getting the ebike kit in the mail and buying the bike, I was ready to assemble everything.

After everything was built I was thrilled and ready to start riding. I got on the bike, rode down the street, then this happened:



As you can see the forks on the bike broke off completely, now I need to look for a new bike.

After doing some research I am going to need to buy torque arms to attach to the side of the bike forks to prevent this from happening again, so I already now have those on order.

But now I need a new bike. I am looking for a bike preferably under $250. Basically my only must-have for the new bike is the cheapest bike possible where this won't happen on it. I found this bike at target that looks like it might work:

http://www.target.com/p/huffy-men-s-alpine-mountain-bike-26/-/A-50769614?ref=tgt_adv_XS000000&AFID=google_pla_df&CPNG=&adgroup=&LID=700000001170770pgs&network=g&device=c&location=9016895&gclid=Cj0KEQjwyozABRDtgPTM0taCrKsBEiQATk6xDgkgZWwJbN2nmIFyVt1h-Gb-INyg1OtkNy4eGrh-MD0aAhbk8P8HAQ&gclsrc=aw.ds

But I am worried that even after I attach the torque arm, the bikes front forks will just snap again. What should I do?

 

[brumbrum]

Take a magnet with you and see if it sticks to the forks, as steel forks will be stronger and less prone to snapping without warning like aluminium does. Steel is more likely to bend first.

 

[nutnspecial]

__ assuming that's a 1 1/8 strait steerer susp fork___

Although I'm fairly certain guys run 1kw on them with proper torque arms, steel dropouts are better.
But there's not many options for a steel susp fork, and likely that huffy has an aluminum fork too. I have seen steel susp forks on the cheapest bikes, but the susp is basically worthless @ that pricepoint.

So why not just get torque arms and a replacement fork?
Amazon/ebay forks (suntour) $75-100 will obviously be so much better than what comes on that huffy for 125$. . .
Or something like this would hold up great and be cheaper http://www.ebay.com/itm/Chromoly-Steel-Rigid-MTB-Fork-26-1-1-8-Threadless-Chrome-/311673036691?hash=item4891291f93:g:z8wAAOSwHoFXqkx3

 

[MrDude_1]

The bike isnt ruined because the fork is broken.
Change the fork out for a stronger one, and use a torque arm on it this time.

A torque arm is a little piece of metal that keeps the axle from rotating in the fork. Without it the lips spread and the wheel rips out.

 

[CUDAcores89]

The bike isnt ruined because the fork is broken.
Change the fork out for a stronger one, and use a torque arm on it this time.

A torque arm is a little piece of metal that keeps the axle from rotating in the fork. Without it the lips spread and the wheel rips out.

Thanks for the heads up, but there is no way the front fork can be removed. The bolts holding in the handlebars and the fork are all rusted shut, so I can't remove it. Oh well, time to look for a new bike. I'm also looking at getting a better bike like the trek 820 or the Giant Revel 2, removing the stock fork and replacing it with a steel one.

 

[MrDude_1]

The bike isnt ruined because the fork is broken.
Change the fork out for a stronger one, and use a torque arm on it this time.

A torque arm is a little piece of metal that keeps the axle from rotating in the fork. Without it the lips spread and the wheel rips out.

Thanks for the heads up, but there is no way the front fork can be removed. The bolts holding in the handlebars and the fork are all rusted shut, so I can't remove it. Oh well, time to look for a new bike. I'm also looking at getting a better bike like the trek 820 or the Giant Revel 2, removing the stock fork and replacing it with a steel one.

dont give up so easily. It could be welded together and its still possible to get it apart.
take some pics so we see what we're looking at and I can give you a cheap plan of attack..

Unless you just really really want a new bike.. in that case, go for it. Just be sure it has enough triangle space for a pack if it has suspension, and if it has a suspension fork be SURE its a strong name brand one. Walmart quality forks wear their bushings out pulling the bike along.

Personally if I could give teenager me advice on projects, I would tell myself to stop buying brand new stuff and work with what you can afford. Same result but much happier about it.

 

[dogman dan]

You will also need two C washers to go with the torque arms. They fill the cup in alloy forks, some steel forks, so the torque arm and nut can lay flat. Chances are, you put micro cracks in your fork just tightening the bolt without the C washers.

Also possible to grind down tabbed washers, to small enough to fit the cup.

 

[CUDAcores89]

OK so I ended up reselling the old bike for $50, so at least I got my money back. Now i'm looking for a new bike. So far I have heard that I need a bike with steel front forks since my hub motor will be mounted in the front but I am encountering another problem, there aren't really any mountain bikes currently out that use a steel front suspension, they all use a stupid aluminum suspension which will just break again. So I decided to go to craigslist to see if I can pick up an older non-suspension type bike, I think I found one, would this work?

http://annarbor.craigslist.org/bik/5819117541.html

This one is made if aluminum, so I would have to change out the front fork for a steel one, but how the heck do I do that?
http://annarbor.craigslist.org/bik/5804749433.html

From what i have read so far is that if I buy a new bike I will need to make sure it has steel front forks. I can buy a new steel front fork for the bike I choose to buy but I have no idea how to change out a front fork with a new one, and I also don't know which front fork to buy to make sure it will be compatible.

Basically here is what I am asking. Is there ANY way at all I can make aluminum forks work with a front hub motor? This is the first time i've ever built an ebike and I live in Michigan, (a very heavily automotive state) so there is pretty much nobody around here that knows anything about ebikes to help me.

 

[MrDude_1]

Changing the fork is very simple. Dont be scared of it simply because you have not done it before. Nothing to it but to do it.

 

[nutnspecial]

https://www.google.com/search?sitesearch=endless-sphere.com&q=front%20hub%20suspension&gws_rd=ssl Take a look at these threads to help with front hub and fork choice. Try other search variations (google option or advanced) for more results.

Besides youtube and google searches, sheldon brown's site has alot of info to answer your question on fork standards and swap-ability. http://www.sheldonbrown.com/gloss_ha-i.html#headset
Likely you'll be looking @ 1 1/8 threadless, all of which (afaik) are interchangeable. There are also the newest higher end 'tapered', and older 1" which I think were mainly threaded iirc. Removal/install of a fork is really easy.
[youtube]lfWns_EfDMw[/youtube]
https://www.youtube.com/watch?v=lfWns_EfDMw
http://www.mountain-bike-world.com/mtb-forks/

That trek bike would work. I had an 830 that I loved, but my buddy's 820 felt way too upright/casual imo. You should still make sure the axle nuts seat properly, and use a torque device. I just used some diy torque washers on my flimsy old steel huffy frame. So far so good, but at least one arm would not be overkill. If you don't end up with a suspension, I'd get some nice taller downhill tires and thick tubes (I'd get them anyway)- they'll help alot.

 

[CUDAcores89]

Found an even better one. Its a 1998 Marin Bolinas Ridge mountain bike. After doing some digging I found out the entire bike is made of steel, including the fork. And it only costs $10 more than the Trek 830. The brakes and gears on the bike also look better (if you look closely at the trek 830 one of the brakes needs a bit of repair). And since it's an older bike I may be able to talk the guy down even further.

https://detroit.craigslist.org/okl/bik/5826797190.html

 

[Nick R.]

SO I Decided I want to build an ebike...

A couple of details about myself:
I am a teenager and therefore am on a budget. Currently I drive about 4 miles to get to my job where I work. After realizing how much cheaper it would be to own a bike instead of a car to get places, I was all ears.

I did my research. I built a 1KWh battery out of 18650 cells and I bought a front hub motor conversion kit from ebay (which worked surprisingly well for the few seconds I was able to use it). I then went to a thrift store and picked up a used bike for 50 bucks. After building the battery, getting the ebike kit in the mail and buying the bike, I was ready to assemble everything.

After everything was built I was thrilled and ready to start riding. I got on the bike, rode down the street, then this happened:



As you can see the forks on the bike broke off completely, now I need to look for a new bike.

After doing some research I am going to need to buy torque arms to attach to the side of the bike forks to prevent this from happening again, so I already now have those on order.

But now I need a new bike. I am looking for a bike preferably under $250. Basically my only must-have for the new bike is the cheapest bike possible where this won't happen on it. I found this bike at target that looks like it might work:

http://www.target.com/p/huffy-men-s-alpine-mountain-bike-26/-/A-50769614?ref=tgt_adv_XS000000&AFID=google_pla_df&CPNG=&adgroup=&LID=700000001170770pgs&network=g&device=c&location=9016895&gclid=Cj0KEQjwyozABRDtgPTM0taCrKsBEiQATk6xDgkgZWwJbN2nmIFyVt1h-Gb-INyg1OtkNy4eGrh-MD0aAhbk8P8HAQ&gclsrc=aw.ds

But I am worried that even after I attach the torque arm, the bikes front forks will just snap again. What should I do?

First I want to congratulate you, a teen with the savvy to put together a ebike and also works restores my faith in the young. It just seems like all the teens around here where I live are Dorks, now down to work, try all the big bicycle shops in your area some might have a relic that they will throw out and if you emphasize the fact you are a teen you may very likely get it free. There is also the chance you may hit paydirt with places like Faithfarm and other places that collect old clothes and junk. good luck to a great kid. Nick R.