[ifouiripilay]

I'm trying to locate a 20" disc wheelset for an upcoming build for my daughter.

It seems that others have used mt bike hubs on bmx rims but much of the rims I've found are 36hole. I also don't know what to look for in terms of bmx rims.

I might opt to build my own, which would be my first time building a wheelset. But investing in a truing stand and making costly mistakes is something I don't want to deal with. I have only seen Velocity rims and sun ringle 20" mt bike rims.

I'm trying to cater to my daughter's need for a lighter ride. Any insight in wheel building or rims sourcing would be greatly appreciated.

 

[CJH]

I'm trying to locate a 20" disc wheelset for an upcoming build for my daughter.

It seems that others have used mt bike hubs on bmx rims but much of the rims I've found are 36hole. I also don't know what to look for in terms of bmx rims.

I might opt to build my own, which would be my first time building a wheelset. But investing in a truing stand and making costly mistakes is something I don't want to deal with. I have only seen Velocity rims and sun ringle 20" mt bike rims.

I'm trying to cater to my daughter's need for a lighter ride. Any insight in wheel building or rims sourcing would be greatly appreciated.

There are some builds on this sub-forum where wheels have been laced up with less than the available spoke holes in a rim. I think one of the threads had 45 lb rider in the title so maybe try searching that.

Do you know how many speeds you want to run?

 

[ifouiripilay]

I'll be upgrading the kids 7spd to 9 or 10.
I seem to be always horrible at the search function. I'll take another look.

Instead of buying a "lil shredder" that costs more then what I can get for my turner 5spot, I'm waiting for the delivery of a 20" norco spice. And upgrading most of the parts.


Sent from my iPhone using Tapatalk

 

[CJH]

I'll be upgrading the kids 7spd to 9 or 10.
I seem to be always horrible at the search function. I'll take another look.

Instead of buying a "lil shredder" that costs more then what I can get for my turner 5spot, I'm waiting for the delivery of a 20" norco spice. And upgrading most of the parts.

http://forums.mtbr.com/families-rid...-wheel-build-40lb-rider-need-help-891768.html

We're doing the same thing with my son's Superfly 20. I might use the hub and 9 speed cassette of my old 26" hard tail. I herniated a disc in my back shortly after buying that bike and don't think I ever put a lot of hard miles on it. Switched to full suspension for the back's sake so I'm sure that hub is fine.

 

[ETChipotle]

I have a nice CR-18 rim (only 1) that ended up not using because before I took the 20" hotrock apart, I had my youngest try riding the 24" that I had built for her sister. She loved it. So I decided to skip the 20" build and build the other 24" instead.

They still have these rims on the auction site for $30

I've just been using the bikes and v-brake shoes as the truing stand, and was surprised at how easy it is to get the wheels true to my low standards.

It is a 32 hole rim, so it is easy to get an XT or whatever mountain hub that matches to go 10 speed.

 

[ifouiripilay]

Thanks for the link. I'll be reading that up.

 

[CJH]

I have a nice CR-18 rim.

Is that a ~1" wide BMX racing style rim?

 

[ETChipotle]

Probably, I don't know anything much about BMX because that came after I was done with bikes. But it's about that narrow. I didn't get picky about width, because there's only so much out there in 32 hole at my price range.

 

[NYrr496]

Velocity Wheels - Hand Made in USA

MTB270 Rear Disk/MTB Hub - 24/28/32h - QR or 12mm Thru Axle

I used this combo on a 20" bike and it worked out great.

 

[Birdman]

I was researching 20" rims for my daughter's 20" Kona Makena. I have a few 32 hole XT hubs kicking around, and was waiting for a deal on Sun CR-18 rims. You'll need the 406mm ISO version of the rim, IIRC.

I've built a few wheels already, so building up a set from scratch would not be a big deal. Building it up with only 16 spokes would be neat too.

Sun Ringle CR-18 Rim 20" - 406mm ISO in Tree Fort Bikes Rims (cat1485)

JMJ

 

[Viva Borracho]

I built up two sets of 20" wheels for me kids using old XT hubs and Sun CR-18 Rims. Worked out great both time. Got them on Amazon for under $30 a piece. 32 Hole.

If I did it again, I would use the 16 spoke pairing method.

 

[CJH]

Velocity Wheels - Hand Made in USA

MTB270 Rear Disk/MTB Hub - 24/28/32h - QR or 12mm Thru Axle

I used this combo on a 20" bike and it worked out great.

I just stumbled across an old 2013 post of yours where I read about putting the above rims on a Gary Fisher Precaliber.

Did you compare the weight of the bare Aeroheat to bare stock rim on the Precaliber? I want to put a disc brake on the Precaliber which means a new hub and I'm trying to decide if I want to replace the rims or not.

I suppose I could take the wheel apart and weigh the rim but I'd rather leave it intact if I do end up building a whole new wheel.

Thanks in advance.

 

[NYrr496]

Tell you what... If I were to do it again, I'd probably use Velocity Cliffhangers since I'm all in love with wide tubeless now.
I did not compare weights but the Aeroheats were definitely better and probably lighter rims.

A word of warning... The rear hub spacing on the Precaliber is 130. Not 135. Wasn't too much of an issue for me because we did Vee brakes and an older XT hub. We just played with the axle spacers a little.

 

[CJH]

A word of warning... The rear hub spacing on the Precaliber is 130. Not 135. Wasn't too much of an issue for me because we did Vee brakes and an older XT hub. We just played with the axle spacers a little.

I just went down and did a quick tape measure job and that sure looks to be the case. I'll pop the wheel off and measure with calipers later but it looks like it could even be a hair under 130mm.

Is this going to make it tough to run disc brakes? I'm open to hub suggestions.

 

[NYrr496]

You'll probably have to run a Shimano hub with ball bearings and install a shorter axle and spacers as per required.

 

[GrayJay]

If you want to go really lightweight, stay with rim brakes and use a 130mm road hubset that is below 300gr total weight (front & rear hub). Road Hubs

For a 20" wheel, 12 spokes (or 16 paired spokes on 32 spoke hubs) is plenty, completely bulletproof for a 50pound kid if the wheels are build well.

Re-using stock singlewall 20" rims will likely be lighter than buying new rims made from extrusions that were designed to withstand adult weight use.