The rear wheel on the snow/sand phattie bike is made up of a Salsa 170mm hub and a Fat Sheba rim (gottsta' love that name) that is 80mm wide. The 170mm spacing for the rear hub is 35mm wider than a regular 135mm rear hub. The 9:zero:7 frame is built specifically to be able to handle the wider hub without having to offset the rim such that the wheel rubs along the drive train. The 170mm spacing allows for a symmetrical wheel build for wide rims/tires.
The wider the rim, the more float on soft surfaces and the better the ability to be able to ride on top of that stuff based on the contact area of the tire. The penalty for wide rims, hubs, tires, tubes is that there is more material and you pay the price with a significant weight penalty.
The work around to lighten wheelsets up has been to drill out the rims between the spokes in order to shave some weight. The 80mm aluminum rim and spoke spacing/lacing allows for 1.5 inch holes between spokes.
The plan was to use a hole saw to cut out the holes and then debur the hole's sharp edges with a deburring tool. Before doing that, I created a template that would fit between the nipples on the rim so that the holes would be drilled in the same place each time - sorta kinda wanted to make sure the holes were spaced equally, etc...
so the process ended up a little like this:
Measure the width between channel and length between the spokes and cutout a template and marked the center with an X. This gave me the centerpoint for each hole.
I then used a hole punch to mark the spot that would later be drilled out with a hole saw and pilot bit.
If you look carefully, you can see the hole punch mark:
Once the wheel was marked, it was time to drill 30 holes....1/2 way there...no turning back - no testing the waters - jump right in, the water is warm!
It was rather messy with lots of aluminum shavings everywhere:
All holes drilled - I did not drill the section where the seam was and obviously did not drill where the valve hole is
about 300 grams worth of rim....I have not weighed the wheel or the parts yet but most people seem to have saved a little over 300 grams worth of weight
Once everything was drilled, I used a deburring tool to smooth out the sharp edges on the holes. It took a while as there are 30 holes and the holes needed deburring on both sides of the rim (inside where the tube will sit and also outside as shown here)
voila - the Graceful Fat Sheba rim after her gastric bypass....
peeeeekaaaaaboooo
phewwwww....doing something new on a new purchase is always a little on the anxious side but fortunately it turned out well and it was an easy thing to do - messy, a little time consuming, but easy once you had it all set up with the right tools.
Next step....need to get some ribbon or reflective tape to place as rim liner/strip in order to contain the tube when inflated.
The big unknown is whether it can be ghetto'd for a tubeless set up (especially with the new drilled out rims) - more experimentation at a later date....
The wider the rim, the more float on soft surfaces and the better the ability to be able to ride on top of that stuff based on the contact area of the tire. The penalty for wide rims, hubs, tires, tubes is that there is more material and you pay the price with a significant weight penalty.
The work around to lighten wheelsets up has been to drill out the rims between the spokes in order to shave some weight. The 80mm aluminum rim and spoke spacing/lacing allows for 1.5 inch holes between spokes.
The plan was to use a hole saw to cut out the holes and then debur the hole's sharp edges with a deburring tool. Before doing that, I created a template that would fit between the nipples on the rim so that the holes would be drilled in the same place each time - sorta kinda wanted to make sure the holes were spaced equally, etc...
so the process ended up a little like this:
Measure the width between channel and length between the spokes and cutout a template and marked the center with an X. This gave me the centerpoint for each hole.
Next step....need to get some ribbon or reflective tape to place as rim liner/strip in order to contain the tube when inflated.
The big unknown is whether it can be ghetto'd for a tubeless set up (especially with the new drilled out rims) - more experimentation at a later date....
Hi - Just curious how much weight she lost? I was thinking of doing the exact same thing.
ReplyDeleteNever mind, I missed the part about 300 grams...
ReplyDeleteGood luck with the drilling! It seems worse than it really is - just drill straight down so you don't drill at an angle and hit a spoke. I have one spoke that suffered a little collateral damage. It also makes a bit of a mess. I used a tarp on the last rim and that made it much easier cleanup-wise...no filaments in the rug, etc...
ReplyDelete