anyone ever convert a downhill mountain bike to electric?

[andys]

From time to time I search for free ride or downhill mountain bikes on ebay, and can't help thinking what a cool electric ride one of them would make. With their massive brakes, tons of suspension travel, and indestructable frames, they are pretty much like off road motorcycles without the engine, and would be a great candidate for a 72 volt high power hub motor. Has anyone built one of these into an electric monster? Any photos? ? I know one issue could be some come with 150mm spacing on the rear frame instead of 135mm, but some creative use of spacers could probably take care of that. And how to mount the batteries. This is the kind of bike I am talking about.

http://cgi.ebay.com/06-Jamis-Diablo-DH-Mountain-Bike-Downhill-All-Medium_W0QQitemZ260261474253QQihZ016QQcategoryZ98083QQssPageNameZWDVWQQrdZ1QQcmdZViewItem


http://cgi.ebay.com/Iron-Horse-7-POINT-Freeride-Downhill-Mountain-Bike_W0QQitemZ260262165053QQihZ016QQcategoryZ98083QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 

[johnrobholmes]

I am in process of converting my santa cruz bullet. Almost a downhill bike, but for my 150lb self it is plenty for anything in my area.

 

[Drunkskunk]

There are a few Norco's here, and atleast 2 Kona Stinky's. I'm one of those, and actualy finnishing up the Kona build right now.

The older style Stinky (Mine's an 04) had a huge space in the main triangle for stuffing batteries, as well as a beefy frame and 8 inches of travel.

Ebay is one place to look, but I bought mine from Pinkbike.com. There's a far greater selection on Pinkbike than on Ebay for Free ride and DH bikes and parts.

 

[fechter]

The biggest problem is where to put the batteries, since the frame is mostly filled in wtih suspension stuff.

Below are a few of my favorites. Sorry, I don't have any details on any of them.

Creative use of duct tape. :wink:

 

[Mark_A_W]

http://www.e-mtb.com.au

 

[andys]

thanks for the photos and the ideas about the Kona. I may keep my eye out for a 2004-2005 Kona Stinky bike or frame for a future possible project.

Andy

 

[trappermike]

I purchased an inexpensive downhill bike for about $350,a CCM from Walmart about 3 years ago as the test mule for a 5304 motor and a 36v-35amp box.Power was a Li-ion 36v-12ah battery.An excellent combo,great suspension and brakes.It would do about 40kph and had good range.BUT on take-off one day the motor broke out of the front forks,I was so happy I was stopped and not doing 40kph!! I put new forks and gusseted and reinforced them.Now I am in the process of going to 48v and adding LOTS of goodies....If I can load a photo of it,it is when I first built it,in a pretty bare,"Plain Jane" state.
A downhill bike cofiguration is all I'm interested in,excellent suspension and handling,and a really tough frame design.
I would reccomend doing a rear motor only.
Hmmm....Dammit,I can't remember how to add a photo here,I'm not too computer savy...

 

[rguy56]

I intend to convert a Giant DH to electric, but not just because it's a big robust bike, but because I want to take advantage of the through hub on that fork. I really think that a front hub motor will work with that design.

The problem in my mind is to go from what I think, offhand, is a 30mm cylindrical axle and adapt that to the threaded axle on the hub motor. There wouldn't be any danger of axle spinout, and acceleration force on the overall structure would be nothing to that fork.

Bob

 

[trappermike]

Here is a photo of the bare bike,when first complted,without accessories....

 

[Mark_A_W]

Photo?

Wot foto?

 

[Ben]

You mean you can't see it?

 

[trappermike]

Look guys,help,I'm trying to post photos,unsuccessfully...I don't know how,I'm new to computers...

 

[rguy56]

I've found that confusing, also.

I think you just go to the Img button above, and it lets you browse, then, for a picture. I think, from there, you select the picture, and go to your edit menu, copy it, and enter it on this little box you're typing in. I think it you'll be inserting it between "(img) (img)" on that page.

If you want to see if it worked, click on the preview box at the bottom.

If you're not really quick trying this out the page might time out on you, but good luck, I know I'm interested in your project.

You have my sympathies, I know I have problems making computers do what I want. If my instructions don't work, you have my apologies, too.

Bob