This is what I use to stretch out the rear frame on my Hyper beach cruiser...that "rope" you see is actually parachute rip cord from the AFB that I chose because you can't break it under this kind of pressure applied.
You just rap the rip cord around the left side of the rear frame where it drops down to as close to the mag hub as you can get and loop it over the movable part of the Dewalt clamping tool which you can see I reversed the direction of the trigger movable part...As the stationary end is braced against the other side of the rear frame, you just keep pulling the trigger and the rip cord pulls the left side of the frame for me so I can place my mag rim into the drop downs.
(The tool itself is too long in between the rubber pads to fit in between both sides of the rear frame, hence my use of parachute rip cord)
Of course, the mag has to be in position in the wheel well area and this device fits in between the three spokes area in order to do this, I doubt you would be able to use this method with conventional spoke rims.
I also have to use an additional axle nut screwed down on the left side to where it meets the wheel itself with the flat side of the nut facing the dropout so that when I release the pressure off the Dewalt tool, the disk brake rotor will have clearance enough to not come in contact with the frame.
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