Disc brakes on leader doberman which has no tabs and adaptors I have a leader doberman with a front disc brake that I want to install on the rear. I know that it hasn't a rear disc brake tab, but I have found an adaptor for the caliper (http://www.ebay.com/itm/Bike-Disc-brake-bracket-frame-adaptor-3-sizes-for-140-160-180mm-rotor-free-gift-/271571281671?pt=Cycling_Parts_Accessories&amp;var=&amp;hash=item3f3ae8e707)



Now I don't know how to mount the rotor, but I have found something to mount it (http://www.ebay.com/itm/E-bike-double-hub-nut-ISO-44mm-thread-Disc-brake-rotor-adaptor-mount-left-Alum-/281474670783?pt=US_Chainrings_BMX_Sprockets&amp;hash=item418932a0bf).



But is this compatible with my rear hub? What can I do? Only to stich it with glue or there is a solution?


I have the classic Shimano gear levers. Will I have to change the shifters to install hydro disc brakes?
Why do you want to install rear discs? Keep in mind a decent set of disc brakes costs as much as this entire bike. The cost of making any improvements to this model bike is almost certainly not worth it.  

Best advise I can give is just do not go there. It results in an expensive, unreliable and often dangerous solution to a problem that does not exist in a majority of cases. If you want a better bike, sell it and buy a better bike. 

Even if you can put an adapter on to the frame, it affects wheel removal and makes all maintenance task twice as hard. You need a new hub - which practically means a new rear wheel. You won't be able to buy a rear wheel for less than the bike is worth second hand.  

90% (100% if you read Sheldon Brown) of your braking comes from your front brake. A good V Brake will brake as effectively as a low end disc brake in 90% of conditions, and on the rear wheel, won't make a significant difference in the other 10% of conditions.