China Blue

[Wildcat]

I've got time for another build before the Annual Build Off. I looked at this new Chinese MTB my wife bought for me. (I tore it apart as soon as she left the room)
The frame is 16" and it looks like a BMX frame so I sized it up with some bars and stem. This will be a 26" BMX.
I've got rims and tires but need to get spokes and lace them up. The frame has bosses so it'll have V brakes. The crankset is ordered along with the 48 tooth chain wheel. Seat and stem also. I've got a freewheel hub and that should be about it, not a whole lot to do. 16 or 24 tooth cog? I could peel off all the decals.

 

[Wildcat]

I went through and pulled out a lot of good parts to use. Spokes are ordered and I think I have everything I need.

 

[Wildcat]

This frame is pretty close in size and shape to my 1982 Cyclepro I bought new in Alameda. Like this one only in black.

 

[mikeeebikey]

For a 48t sprocket with 2.125 or bigger tires you would need about a 22 or 23 rear...
I'd go 48/23 because I'm a wheelie guy.

Cool looking frame.

 

[Wildcat]

My choices are 16 or 24 teeth on the freewheel, that's all they have around here and I have one there in the middle of the table that needs oiled up so it'll get used. 48 tooth chain wheel with a 24 cog, 2-1 ratio should be good for the trail and city streets. Now the question is red hub on front, blue in back or vice versa?

 

[MattiThundrrr]

I like the bmx rato as a starting point, here's the equation they use
2X+2, take the rear tooth count, multiply by 2, then add two to get the front.
ie 32:15 or 34:16 or 36:17 or 32:15
It's pretty hilly where you are at, so dropping a couple of teeth of the crank will probably be good for yours

 

[Captain Awesome]

Red hub front as a focal piece

 

[Wildcat]

I checked my spokes order and yes, every last thing on this bike is made in China.

 

[Wildcat]

I found some sprockets, 20 and 22 tooth and ordered them. I'll do a flipflop hub on the rear, and could add two different sprocket sizes to the front, they are both rear hubs. Maybe a 16 and 22 in front, 20 and 24 in rear. Then I'd have 4 ratios to choose from.

 

[Wildcat]

Instead of a derailleur I ordered up a tensioner.

Made in China of course. Looking at the ratios, I'm going to use a 39 tooth chain wheel with 22 and 16 teeth sprockets on the hub. The flipflop will give me a decent street gear of 64 gear inches and a low gear at 46 GI. For very low gear I'll have a 24 on the front wheel for 43 GI. All this will need is a 15mm wrench to swap gears. The seat arrived today, now just waiting for spokes and the seat stem.

 

[Wildcat]

I dug out my laid back post and used my homemade sleeve so it would fit this frame.

I saw this hub at the bottom of the pile and realized it would work on this bike as a backup wheel or as a primary. It's a 2 speed auto, shifts at about 10mph to a higher gear then drops back to direct drive when you slow down. It's not made in China, I think it's German.
I gathered up all my spokes and had just enough to do this wheel. 4 cross pattern was all that would work. A mix of silver and black but I tried to space out the black spokes so it looked like maybe it came that way.

Now this one is ready for truing at the shop.
I'll have two sets of wheels, one blue and one black when I'm done.
While waiting for the new cranks, I put on the original triple chain wheel for now. With the existing rear derailleur I can have the option to shift up or down with 28, 38, and 48 tooth chainwheels. With the auto 2 speed hub would give 6 speeds. But when the new crank and chainwheel show up, it'll be a 39 tooth chain wheel with an 18 tooth on the SRAM auto, or the other wheel with the cogs.

 

[Wildcat]

Nope, the SRAM Automatix was made in Taiwan made but still close to China. "In 2013 production of internal gear hubs moved from Germany to Taiwan. "

 

[Wildcat]

I had a 24 x 1 3/8ths wheel that has the same inside diameter as my 26" rim. The deep V makes up 2 inches, so those spokes will work on the bigger wheel.
So I laced it up this morning and did a mock up. I think I'll try my wife's hairdryer to get the stickers off.

 

[Wildcat]

I had a wheelset made up using my old skiptooth Bendix hub that didn't work out. The old Bendix is the same size hub as my freewheel hub, so I changed it out and have my primary wheelset ready just need truing and the other sprockets to show up. The front will have the 22 and the rear 20 and 24. Either a 39 or 48 chain wheel.

 

[us56456712]

Instead of a derailleur I ordered up a tensioner.
View attachment 153596
Made in China of course. Looking at the ratios, I'm going to use a 39 tooth chain wheel with 22 and 16 teeth sprockets on the hub. The flipflop will give me a decent street gear of 64 gear inches and a low gear at 46 GI. For very low gear I'll have a 24 on the front wheel for 43 GI. All this will need is a 15mm wrench to swap gears. The seat arrived today, now just waiting for spokes and the seat stem.

That’s spiny enough for my old legs. Way back road racers had to flip wheels for hill climbing, no derailleur. The mans gear and the woman’s gear. It shouldn’t be too time consuming to do. Nice idea you have there.

 

[Wildcat]

That’s spiny enough for my old legs. Way back road racers had to flip wheels for hill climbing, no derailleur. The mans gear and the woman’s gear. It shouldn’t be too time consuming to do. Nice idea you have there.

I like the look of blue rims on that bike, if I keep the 2 speed auto on there I'll have gear indexes of 57 and 78, might be okay with that or maybe add a larger cog to drop the gear lower.

Then these flipflop wheels will require getting another frame to be built up as an even bigger BMX.

Possible candidate for the annual build off.

 

[Wildcat]

I like the bmx rato as a starting point, here's the equation they use
2X+2, take the rear tooth count, multiply by 2, then add two to get the front.
ie 32:15 or 34:16 or 36:17 or 32:15
It's pretty hilly where you are at, so dropping a couple of teeth of the crank will probably be good for yours

So, I have an 18 on the hub, and the middle chain wheel on the triple is a 38. so, 18+18+2=38. I'm all set! With a tensioner, I can drop to the smaller 28 chain wheel.

 

[Wildcat]

I had a 24 x 1 3/8ths wheel that has the same inside diameter as my 26" rim. The deep V makes up 2 inches, so those spokes will work on the bigger wheel.
So I laced it up this morning and did a mock up. I think I'll try my wife's hairdryer to get the stickers off.

View attachment 153713

Stickers came off easily with a hair dryer, just residue to clean up. New cranks and 39 tooth chain wheel added.

Blue grips and brake cables ordered. 19 tooth cog on the 2 speed hub instead of 18, the others didn't fit tightly like the SRAM cog. Adding a washer didn't help. so I have a 54/74 gear range.
We've had a big outbreak of Covid so everything's locked down again or too much hassle to travel to town. Luckily my digs are setup for the long haul if need be. The wheels need truing and will have to wait.

 

[Wildcat]

The blue grips arrived but no cables or brake pads yet. The rims still need truing too.
This first pic is with the SRAM 2 speed. I may use this configuration the most because of the auto shifting and blue rims.

The 2nd pic is with the dual wheel flip flop system, cogs of 16. 20, 22, and 24 teeth. The 16 hasn't arrived yet, I just threw on an extra 24 for looks. The chain will be a longer one with the tensioner to fit the other cogs, the length of this one works with only the SRAM and the 20 tooth cog. It will need just a 15mm wrench to change to any of the four gears.

 

[Wildcat]

My long awaited black spokes showed up! They actually were 72 spokes per bag. 8 bucks each, 16 dollars for 145 spokes total. Of course they are from China, in keeping with the theme of this build. I laced the wheels, 4 cross pattern, and am now waiting on the set of tires I found on a different shopping site, Shopee. Like Amazon. Tons of bike stuff.