Shimano I-Spec2 Shifter Handlebar Mount

For those that have bought an I-spec 2 shifter but don't have the correct brakes to mount it to (or don't want to buy and expensive adapter). You could very likely adapt the idea yourself to make something that suits a different shifter, but the Ispec2 type was the solution i needed...

this can be found on thingiverse if you just want to skip to the last step and print it ;)

https://www.thingiverse.com/thing:4932867

Hobby license for fusion 360

vernier calipers

small ruler

m4x25 bolt and nut

m4x20 bolt and nut

a couple of hours spare time to learn how to use some of the fusion controls

a slicer program (i use cura)

a 3d printer (this was printed on a creality ender 6 using ABS filament)

Create your main clamp loop. The bar diameter at the controls is 22.2mm, and i wanted a fair amount of strength for this so i've gone fo an outer diameter of 32mm.

create a 32mm circle, starting at the centre of the axis points

now extrude it out to 20mm

next, we need a way to clamp this thing tight when we mount it. i'm using m4 nuts and bolts because that's what i have lying around, this has been more than adequate for months of riding.

draw a circle halfway up the centre line of the clamp

now extract that 10mm in one direction, then 10mm in the other

now we'll need somewhere for the shifter to mount to, we'll start with a nice thick tab off the main clamp.

Draw a 10x10mm box at the side of the clamp (making sure the corners overlap the circle)

extrude this up 20mm

Because the shifter mount face isn't a flat surface, we'll need to make a small arc for it to fit snugly to.

draw an arc from the box join to 2.5mm down the opposite face

extrude this section -20mm to remove it

(optionally, you can add a small gussett to the opposite side of the tab for strength)

The shifter also has an inset on the mount to prevent rotation, we need to make a block that fits into that.

draw a 6x5mm square off the bottom of the tab

extrude this up 15mm

extrude -5mm off the bottom to make it 10mm wide

its not going to work very well if we cant bolt the shifter to the clamp, so we'll need a hole for the bolt.

draw a 4.2mm hole (to give the m4 bolt enough room) in the middle of the block

extrude -15mm to create a hole through the block and tab

(optionally, you can make an inset for the nut on the inside of the tab)

The clamp will also probably work better if we have a way to bolt it together, so lets make another bolt hole.

draw a 4.2mm circle on the face of the cylinder we made earlier

extrude this -20mm to create a hole

(optionally, you can make an inset for the bolt/nut at either end)

Things are starting to take shape for real now, lets get this thing ready to slip onto the bars

draw a 23mm circle in the centre of the clamp (23mm so it slides over the bar easily)

extrude this -20mm to create a hole

For the last step of the functional parts, we'll need a gap for the clamp to tighten.

draw a 10x2mm rectangle going through the middle of the clamp and bolt section

extrude +20mm to create your gap

And finally, we'll tidy up the edges of the mount so its nice and smooth.

select all the outer corners on one side of the clamp, and use the fillet tool at 1mm

rotate the clamp view, and repeat on the other side

(Optionally, you can add text or a logo to the outer face of the clamp, i put a nickname on my daughters one)

PRINT IT!

I suggest printing in ABS as its both stiff and resistant to weathering. PETG might be an option, but may be a little too flexy for the purpose. i don't recommend PLA for this one, i dont think it'll hold up.

Print at 100% infill for max strength

Print with the clamp face side down so the layer strength loss isn't an issue

Use supports to assist with the overhangs.