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Converting 20mm hub to 3/8"???

Cru Jones

Turbo Monkey
Sep 2, 2006
3,025
2
Hell Track
Can it be done? I just busted up my 2nd Gold Label and need a new fork. I'm thinking about picking up the Black Market rigid, but it has 3/8" (10mm) dropouts. I don't really want to buy a new front hub. What are my options?
 

Stoked

Turbo Monkey
Nov 28, 2004
1,809
1
LI, NY
maybe a marz d-street axle. might have to grind the rigids drop outs a lil.
identiti has a crazy axle system...14/20. still gonna have to grind the drops.

hmm im tapped

btw what broke on the fork?
 
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opjones

Monkey
Aug 17, 2006
678
0
Detroit
Bummer, was it the arch that failed?

I remember this topic coming up on this board before. Here's what i came up with my search.

http://www.ridemonkey.com/forums/showthread.php?t=183723
^Chuffer thinks that QBP sold something, but no links.


Found this also, this is along the lines of what I was thinking.

" The third option for the homebuilder would be to take a 20mm axle disc hub(about $70 Cdn), make some aluminum adapters that slide into the 20mm hole and reduce it to something more usable like 12mm or 1/2". "

My thought was to take a 20mm rod and cut it down so it's only 1/16 longer than your hub, and then tap the ends to whatever thread you want. You'll want someone with a lathe to help you out. Now if someone sells something like this I don't know, but i would think so.
 

Cru Jones

Turbo Monkey
Sep 2, 2006
3,025
2
Hell Track
Now there's an idea.

So, it sounds like there's not a quick an easy way to do it with something that's on the market already?

Yeah, I snapped the arch on my gold label. That was the 2nd one that I busted. On the first one I bent the steerer tube. But, in all fairness, both instances of the breaking/bending were freak accidents that would have destroyed a lot of forks. I like the gold label, just don't feel like paying for another. Plus, after lots of time on my bmx, I don't think I need any squish on my rides.
 
Mar 27, 2007
263
0
LA, CA
Just get the Black Market fork. It looks way better anyways. The trailblade has disc tabs too, which I know you wouldn't shave off.
 

Savage_Animal

Monkey
Feb 3, 2008
658
0
Norcal
I have a 20 Halo SAS wheel, what I got was the conversion kit for it. I am sure that you could easily put the kit on another hub. I can run QR or Bolt on as well:





I actualy have two, because one got busted, but i'll send you it if you want to see if you can fix it, its the bolt on one. PM me.
 

JJJKKK

Chimp
Dec 8, 2007
41
0
Basic '20mm mtb kitted' Marmoset w/o extra 5mm spacers OR w/o wider cones will do.

Use the original collars and og Marmoset axle w/ those "bearing lips" shaved off. Then it'll be 100mm wide and the axle will just slide in but pls note you need to tighten down the bolts even to make it work.




Then if you wanna swap the wheel back to suspension fork, just add the 5mm spacers/wider cones take off the Marmoset axle and replace the axle of suspension fork.

This might not be helpful for your problem though but I'd like to share this idea.
 
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GMDesigns

Chimp
Sep 27, 2006
94
0
OH
Cru,
I'm actually making an axle right now (well not RIGHT now) to adapt a 20mm Profile non disc front hub to a Black Market rigid for a friend.

If you need anything, I'd be happy to help.


GM

JJJKKK: That's a good idea for those who already have a Marmoset and want to switch between axle mounting configurations.
 
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Cru Jones

Turbo Monkey
Sep 2, 2006
3,025
2
Hell Track

GMDesigns

Chimp
Sep 27, 2006
94
0
OH
Yes Cru, you'd have to turn those shoulders down to the OD of the axle. Then it will slide in your existing 20mm hub. You still need some sort of cone / spacers that will result in an overall width of 100mm though.

But I suppose if you can turn the axle down, you can also remove 5mm from each side of whatever spacer you have now...maybe.


GM
 

Cru Jones

Turbo Monkey
Sep 2, 2006
3,025
2
Hell Track
Yes Cru, you'd have to turn those shoulders down to the OD of the axle. Then it will slide in your existing 20mm hub. You still need some sort of cone / spacers that will result in an overall width of 100mm though.

But I suppose if you can turn the axle down, you can also remove 5mm from each side of whatever spacer you have now...maybe.


GM
Ummm... how long would it take to grind down those shoulders on a sidewalk? That's about the only way I have of doing it. :busted:

Thanks for the offer Greg. I may take you up on it. I need make a decision and order the fork first. I'll let you know.
 

ebrider510

Monkey
Dec 7, 2006
410
0
Bay Area, CA
you have atomlab hubs right? i think they make a conversion thing for their 20mm hubs to bring them down to 3/8's or so. also look into the identiti rebate rigid..cheaper and cleaner then the DMR but is available with a 20mm axle. the 20mm is actually awesome because the thru axle is super simple an modeled after a 14mm BMX axle. check it out.
 

don

Turbo Monkey
Nov 8, 2001
1,319
0
Rumson, NJ
The fork is the most fustrating part of my USB right now. The Manitou Jumper I have is about 3 years old and I'm starting to worry about it. I have a Marz Z1 in the shop but haven't had the time to take it apart again, get the height right, and grind down the disc tabs. The Atomlab fork? I don't even want to think about the time and money spent on that thing.

At any rate, I've been thinking the same thing Cru - that BlackMarket fork as a replacement. My only worry is that it would be too short. I have a Profile 20mm disk hub that I've been wanting to swap for either a Maramoset or Profile non-disk 20mm or I could go that BlackMarket and go back to 3/8" axles.

Sorry about the rant, at any rate, I'd like to see what direction you go with a fork replacement...
 

Cru Jones

Turbo Monkey
Sep 2, 2006
3,025
2
Hell Track
My only worry is that it would be too short.
That's one of my other concerns with it. My gold label has a 480 a2c. The blkmrkt is 435. That's a huge difference. I don't think I'd mind the head angle getting steeper, but it would also lower the bb quite a bit, which I definitely don't want.

Sorry to hear about your fork frustrations. I know where you're coming from.
 
because the green simpleton has such a silly high bottom bracket, the s&m fork would be a perfect match for your frame IMO. your bike could use a little steepening anyway, it steers like a freakin' sled. it would then feel and ride like an identical version of the brown bull...

oh yeah, i think you should ask mike if he has something for your hub, i'm pretty sure he does...
 
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jamesdc

Monkey
May 6, 2007
469
0
I may still have a conversion kit for a front azonic hub lying around that you might be able to rig up to work. I'll check tomorrow if I still have it. As far as the fork goes you might want to avoid the dmr, didn't joe bend the sh!t outta one of those at skatelab.
 

cornfed

Monkey
Jul 30, 2007
199
0
I like the S&M...I mean BLKMRKT fork. You will get used to the shorter A2C. In fact, if you try going back to the longer A2C, I'd bet you won't like it. I like it alot:



 

Cru Jones

Turbo Monkey
Sep 2, 2006
3,025
2
Hell Track
because the green simpleton has such a silly high bottom bracket, the s&m fork would be a perfect match for your frame IMO. your bike could use a little steepening anyway, it steers like a freakin' sled. it would then feel and ride like an identical version of the brown bull...

oh yeah, i think you should ask mike if he has something for your hub, i'm pretty sure he does...
The silly high bb is the key to it's radness. It's not even silly high... 13 = perfect (or, maybe a little low) & boostitude. I'm all for the steepening.

Yeah, I saw some conversion cups on atomlab's site. It says they will convert 20mm to 9mm skewer. But, I'm not sure I'd be able run a regular axle with these. I think I might have to use quick release. Anybody know?

http://store.atomlab.com/llp/itemdesc.asp?CartId={70B75090-5EVEREST7BE-4248-B953-944821DE4EC7}&ic=ALHU9mmAdapter&eq=&Tp=

I swear they had an aircorp version up there yesterday. Now I can't find it.
 
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