Convert Ultra powered mid drive 26" Fatty to 27.5"

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
After riding it a few hundred miles now, and trying both 26x4" Origin 8's and Kenda 26x3" street tires, I'm still not happy with how big and heavy the bike feels, not to mention dealing with what seems like excessive rolling resistance. I'm thinking a change to 27.5" (or 650b, whatever) tires would help things considerably on all counts. Trying to move in that direction.

What I'm finding though, is the required rim and hub are near impossible to source, especially pre-laced?

The hub needs to be a 36 hole, set for a disc brake, fit in a 170mm drop out, and be compatible with a 9 speed cassette.

I'd like to find a 27.5 rim that can be run be run with 2.4" - 2.8" tires, so it needs to be a MTB rim that's 36-40mm wide.

I've spent hours looking everywhere and cannot find a pre-laced hub and rim assembly.

Bike is ridden casually for recreation only, so I really can't justify the expense of high end carbon fiber parts.

Ideas?

TIA -Al
 
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PedalUma

Well-Known Member
Region
USA
Just some thoughts,
Amazon has a 48V 750W fat bike motor. Then you could have two wheelsets. Or re-use your existing motor. It looks like with a 170mm drop out you will need to take it to a bike shop that has a spoke cutter. This is precise stuff. Look over Sheldon Brown on his wheel building calculators and techniques. You may want to have them cut the spokes and lace it, or lace it yourself. There will probably be a slight difference in left and right spoke lengths. I mark them each with a dot of nail polish color and mark the first five holes and spokes on each side with unique colors and write a chart to keep things straight. It is so easy to get mixed up when starting the first spokes on each side. Then each additional spoke becomes a routine pattern. Thread lock is nice on hub motor spokes. After you are done the nail polish is easy to remove. The reason I have nail polish around is that I have been taking bikes to the beauty store for years to buy touch up paint. It works great and they have every color. Numbered tags on tape would also work. Fat bikes tend to have offset issues making the low gear hard to access. Double check the chainlike before proceeding. Going with a larger dimeter wheel is like building a longer bridge. Everything will need to be stronger and heavier. So a larger wheel may not solve the underlying motivation.
If this were my ride I would keep the existing wheels and go with the E50 Super Moto-X. These fly.
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
Sorry, I should have mentioned I'm working on an Ultra powered mid drive (Rize Rx Pro). That's a pretty important detail. I've edited the title to the note to add that info. Thanks for pointing that out.

I'm trying to avoid having to lace it myself, but I will if I have to. Offset and spoke lengths are not going to make this a good one to learn on.

I just switched my hub powered city bike, which is also kind of a hybrid, from a set of very stiff sidewall Schwalbe Marathons (26x2") to a set of the Schwalbe Super Moto-X 26x2.4". Only have a few miles on them, but so far anyway, I absolutely love them!! They remeind me of old style balloon tires I ran back in the 60's. That's pretty much the plan for the 27.5 wheels. I did see there are Super Moto-X available in 27.5 x 2.4 as well. -Al
 
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AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
Thank You! They're book marked, and I'll call them tomorrow! -Al
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
Contacted the vendor and with14g spokes, they say they don't feel the wheels are heavy enough for e-bike use, especially when considering my plus size butt.

The search continues!
 

harryS

Well-Known Member
Replace the spokes with 13G sapim strong (13G at elbow, and 14G ar rim). Replace one spoke at a time, and you shouldn't be in too much trouble. About a buck to a buck-fifty each.
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
Replace the spokes with 13G sapim strong (13G at elbow, and 14G ar rim). Replace one spoke at a time, and you shouldn't be in too much trouble. About a buck to a buck-fifty each.
I'll keep that idea in mind. Would not be hard to get the right spokes by just measuring and ordering the same length thats there. Thanks Harry! -Al