Finding a few sub $500 downhill bikes to convert and learn from.

Ken Shopken

Member
Region
USA
Howdy

I have been reading and learning about different conversions and have decided to buy a few sub $500 downhill and fat bikes to practice and experiment upon before building a "nice" bike to own and ride.

Who on this forum has already done this?

Do you have a few tips?

I am looking at different models with enough travel and low enough gearing for the hard climbing and fast descending that I will want to do, but battery placement and size looks to be very challenging. However they are mounted, the placement needs to allow for decent handling and sufficient ah capacity. Perhaps construct multiple batteries linked with available frame mounting ideal areas?

I have included a few examples of sub $500 practice building machines and would appreciate any conversion input.

Here are the battery mounting links I have found on this forum;
 

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That's a used sub $500 downhill bike, right? Sub $500 new is garbage.
That said, fitting a mid-drive depends on the bottom bracket on the donor. So, before you buy the bike see if the motor you wants fits. Battery placement is an issue, so figure that out too. I cut cardboard silhouettes of various battery types and see how they fit.
I have one small FS mtb, that outside of a battery on a seatpost mounted rear rack , which I don't like, nothing fits. Which led me into building my own batteries. That is something I don't recommend.
 
The best place to hang a lithiumIon battery is in front of you. I do not need a big fire ball between my legs, or behind me where cars can smash it to scrap then cram the flame ball up my ****.
The test way to hang a battery up front is from bosses welded in the frame up there. There was a >$5000 specialized mountain bike that had such front basket mount bosses. The only other ones I know of are cargo bikes. As the yuba bodaboda in the avatar shows, with the battery the white triangle up front. Blix packa also has the front basket bosses. The frame the battery rides in is not a basket, it is a cage of 3/4"x1/8" aluminum angle, white 3/4" foam, and 22 10-32 screws with elastic stop nuts. The mount bolts are 2 each 1/4-20x4" with elastic stop nuts. All stainless so no rust after the rain. The battery is a luna triangle shaped shrink wrap one, no actual plastic frame. I've got >9000 miles on it.
If you want to start with a $500 beater, get a welding shop to install 6 mm I D bosses in the down tubes towards the front. Hint, girl's frames provide much better angles for the four battery mount struts than a diamond frame. You will be much happier with a front battery than with some tiny battery wedged out of the way of the suspension action between your legs. I see building your own battery as a complete non-starter.
 
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That's a used sub $500 downhill bike, right? Sub $500 new is garbage.
That said, fitting a mid-drive depends on the bottom bracket on the donor. So, before you buy the bike see if the motor you wants fits. Battery placement is an issue, so figure that out too. I cut cardboard silhouettes of various battery types and see how they fit.
I have one small FS mtb, that outside of a battery on a seatpost mounted rear rack , which I don't like, nothing fits. Which led me into building my own batteries. That is something I don't recommend.
Used and higher quality machines.
 
A rear suspension bike has got to be one of the hardest projects, because there is usually no place to put a commercially purchased battery, Perhaps this is one instance where a store bought ebike is superior,

Otherwise, for pavement pounding bikes, most any beater bike will work if you;re willing to replace everything but the frame, and I've gone down that path,
 
The usual problem is the shock taking up space, you can turn it upside down for more battery clearance or even redrill the holes to move it away.
My f/s fatbike build required me to mount the shock further back, it seems fine and actually given me more travel, just used an air shock and upped the pressure.

There are specific threads on Endless Sphere, if it's not there, its not anywhere.

 
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