Brake disc install on Fuji Odessa, how?

[Smurf]

Hi.
Want to build a mechanic disc brakes instead V-brakes on my Fuji Odessa e-bike.

Need only caliper, disc/pads and adapter(using existing hand levers), right?

On back rim (hub motor) I have 6 holes, think that is fit for standard size disc?
Don't have yet front rim with holes, must buy it.

Holes at front holder caliper are around 51 mm (it seems standard).

But problem is that back holes for caliper are around 20 mm.
Is that really holes for caliper?

If they are, that means must exist somewhere caliper version for that holes? If not, why only exist caliper mount for front, and not rear?
Why someone made a different size holes? No sense to me..

I contacted two services stores which told me that front is ok, and only need adapter for 180 disc(but I heard at YT that no go over 160).
And at back side (service not support that) I can drill extra hole +20mm and install it.
But I can maybe weld too(or not if is aluminum).

Which options are viable to do that?
Don't know many about bike disc, so any information will help.

 

[m@Robertson]

Your frame is not compatible for disc brakes, so you can't add a disc brake adapter to attach the disc caliper to it in back. You do have one in the front and it looks to be an IS mount. So you want an IS mount that is matched to your chosen rotor diameter. Then bolt your calipers to that.

As for the rear, you have only one royally sucky option: Create your own IS mount. Google "IS rear brake mount specs" to do it the hard way, or get something cheap like this and use it as a guide.

Amazon.com

amzn.to

There are many variations on this, and I am not recommending you buy this one. You have your work cut out for you making something that can hold up to braking forces, though.

 

[Smurf]

Your frame is not compatible for disc brakes, so you can't add a disc brake adapter to attach the disc caliper to it in back. You do have one in the front and it looks to be an IS mount. So you want an IS mount that is matched to your chosen rotor diameter. Then bolt your calipers to that.

As for the rear, you have only one royally sucky option: Create your own IS mount. Google "IS rear brake mount specs" to do it the hard way, or get something cheap like this and use it as a guide.

Amazon.com

amzn.to

There are many variations on this, and I am not recommending you buy this one. You have your work cut out for you making something that can hold up to braking forces, though.

Thanks Robertson for information.
I found that bracelet too today for a new option, and seems easy installation. But not sure will holding too long. Saw on YT that it moves after some times and need to adjusted.

It seems my frame is aluminum, so can't weld. Only can drill new hole, then two holes will fit to size of caliper.

So, why someone designed bike with only one front brake disc? It looks stupid idea.

I need to install brake disc, most for rear rim, because after 1 year I got channel in rim (because brakes), and need ti do it before destroy all rim. So, change the rear brake important to me.

 

[m@Robertson]

So, why someone designed bike with only one front brake disc? It looks stupid idea.

They didn't. Whoever originally manufactured your bike just picked a suspension fork off of a catalog list and all such forks have the mounts. In fact, since your fork has IS mounts and not post mounts, I bet its a REALLY old fork. It may not have even been on the bike when it was first sold.

 

[Smurf]

It is manufactured fork. It seems bike made 2005. See pictures:

Preusmjeri Obavijest

images.app.goo.gl

Preusmjeri Obavijest

images.app.goo.gl

And found "white" version with different mount holes (like mine at back):

Fuji Odessa Mountain Bike Online

Fuji Odessa Mountain Bike Online

www.macy-macy.top

Is that two holes 20mm for rear rack maybe?

What will be if I drill extra hole and add caliper there?

Is it better that or bracelet?