Cutting tyre foam - or at least one way

[TWINSET]

Been doing this to TLT tyre foams for a while now

Without foams at all, they're a bit too 'mushy' and uncut foams just don't look good

Plus, cut foams are a bit like running tyres on low air pressure - it gives a slightly bigger contact patch, and the tyre deforms easily around the terrain.

So, just got a new set of Moabs off eBay..........................

With new foam in, the tyre is really packed out - notice the convex shape of the sidewalls where the foam is too big for the carcass, so pushing the walls out;

Get a knife with a long sharp blade, at least the width of the foams

Eventually, I cut about 1/4'' off each side, but to start with, just take it off one side (to leave a flat face for the next step)

The Marking;

Start by dividing the circle into quarters

Then, eighths (that's 45 degrees)

Ok, now take a line from the top of one line to the bottom of the next (this'll create another marking point)

Take a line from that intersection, across the centre hole, to it's opposing intersection

Then, take a line from the top of the new one, to the bottom of each line either side

Ok, the less boring bit - cut from the outside into the V created by all those lines, being careful not to cut past the bottom of the V, leaving this;

With scissors, cut a small bit of each corner off, to give the tyres a more rounded profile (if that's what you want)

Almost done!

Turn foam inside out

Cut a small 45 degree chamfer around the edges (to allow foam to seat inside the beads better - a 5mm x 5mm chamfer is good for starters

Also, if you didn't already, shave the face with all the pen lines on it (the other 1/4'' from earlier)

Finally, turn it back the right way (points to the outside),put it back in the tyre and admire the concave profile of the tyre

[backtomyroots]

Well done [Y] !  However, looks like way too much work for some of us.  I just hack away with scissors - not nearly as scientific !  Nice "How To" post !