Eccentric BB and a singlespeed

[casurina99]

Hi All,

Perhaps someone out there has used an eccentric bottom bracket on a singlespeed conversion.
Some may remember my lightweight frame, that needs to go single. But its got short dropouts, so I need to use an eccentic bottom bracket perhaps.

What is a good brand. Are they a real pain in the bum?

My options oterwise is building up yet another rear wheel... which I seem to have far too many of at present. (Re-dishing the one on the bike isnt an option. Rusted spokes, bodgy rim -trust me its beyond it.)

T

 

[suzyj]

Casurina99 wrote:

> Perhaps someone out there has used an eccentric bottom
> bracket on a singlespeed conversion.

I may be wrong, but I was under the impression that you have to use an oversize bottom bracket shell to use an eccentric bottom bracket. Unless you're pretty handy with the torch (in which swapping the forkends would be a lot easier anyway) I'd suggest using an eccentric hub.

Regards,

Suzy

PS: If it's gonna freewheel anyway, you could always just leave a derailleur in there to tension the chain.

 

[hippy]

"casurina99" <[email protected]
>
> Perhaps someone out there has used an eccentric bottom bracket on a
> singlespeed conversion.
> Some may remember my lightweight frame, that needs to go single. But
> its got short dropouts, so I need to use an eccentic bottom bracket
> perhaps.

What do you mean "short" dropouts? Vertical dropouts?
Ecc. BB's require a fairly huge frame modification - they
don't just screw in - the frame has to have an extra large
bb shell to fit the EBB:
http://www.m-gineering.nl/inbredti1.jpg
(the whole in this is for a 'normal' bb - see the size diff.?)

- You could use an old derailer as a tensioner - very cheap
- You could pick a gear combo that works with no
tensioner and your chainstay length. It might require
some fiddling and maybe a bmx half link but it is also
quite cheap.
- Grind the vertical dropouts
- Buy a commercial chain tensioner ~$90
- Have GripSport fit horizontal "dropouts" (track ends)
- ENO eccentric hub option

Read this: http://mtbr.com/faq/ssfaq.shtml

> What is a good brand. Are they a real pain in the bum?

No idea and 1) Yes, if you're frame isn't built for one, No
if it is.

> My options oterwise is building up yet another rear wheel... which I
> seem to have far too many of at present. (Re-dishing the one on the
> bike isnt an option. Rusted spokes, bodgy rim -trust me its beyond
> it.)

I know Dan from www.atomic-industries.com has some eccentric
ENO hubs in stock. 135mm MTB spacing. I know this because
they sent the wrong ones to him - I had ordered one spaced for
road dropouts.

hth
hippy

 

[casurina99]

Casurina99 wrote:

I may be wrong, but I was under the impression that you have to use an oversize bottom bracket shell to use an eccentric bottom bracket. Unless you're pretty handy with the torch (in which swapping the forkends would be a lot easier anyway) I'd suggest using an eccentric hub.

Regards,

Suzy

PS: If it's gonna freewheel anyway, you could always just leave a derailleur in there to tension the chain.

Thats what I was worried about..

I don't like the chain tensioner stuff - purely aesthetic reasons.

Not so handy with a torch myself though. This is the wiggly light frame of mine, so I wanted a simple fix... Maybe an eccentric hub would be an answer.

But thats another wheel to build up yet again. Obviously Im all undecided about doing this otherwise I'd just run out and build up a new wheel.

Hmm perhaps later in the week.

I'll post frame pics for all those steel lovers out there soon.

T

 

[hippy]

"casurina99" <[email protected]
> I don't like the chain tensioner stuff - purely aesthetic reasons.

Fair call, but I got over it quickly when
costs were mentioned Not so the next
ss..

> But thats another wheel to build up yet again. Obviously Im all
> undecided about doing this otherwise I'd just run out and build up a
> new wheel.

If you have so many wheels - why not build one of your
existing ones into an eccentric-hub version?

> I'll post frame pics for all those steel lovers out there soon.

<starsky and hutch>
DO IT. DO IT.
</starsky and hutch>

hippy

 

[mfhor]

"casurina99" <[email protected]
> I don't like the chain tensioner stuff - purely aesthetic reasons.

Fair call, but I got over it quickly when
costs were mentioned Not so the next
ss..

> But thats another wheel to build up yet again. Obviously Im all
> undecided about doing this otherwise I'd just run out and build up a
> new wheel.

If you have so many wheels - why not build one of your
existing ones into an eccentric-hub version?

> I'll post frame pics for all those steel lovers out there soon.

<starsky and hutch>
DO IT. DO IT.
</starsky and hutch>

hippy

If you knew someone with a lathe, and had a spare BMX (24", maybe?) could you put an eccentric tandem shell into a BMX b/b? Oh, and a welder to put some locating screw holes/nuts in the b/b?

Anybody done this or similar?

M "too much time on his hands" H

 

[hippy]

"mfhor" <[email protected]
> If you knew someone with a lathe, and had a spare BMX (24", maybe?)
> could you put an eccentric tandem shell into a BMX b/b? Oh, and a
> welder to put some locating screw holes/nuts in the b/b?
>
> Anybody done this or similar?

Maaaybe.. but surely it would be easier to
just retrofit a normal ebb? I know this has
been done - it's just usually more trouble
than it's worth. Other than bike shop owners
and 60 y.o. mad bike builders with a large
stash of gear - I don't know anyone with all
the above parts/tools.

hippy
"Good luck!" ;-)

 

[casurina99]

"mfhor" <[email protected]
> If you knew someone with a lathe, and had a spare BMX (24", maybe?)
> could you put an eccentric tandem shell into a BMX b/b? Oh, and a
> welder to put some locating screw holes/nuts in the b/b?
>
> Anybody done this or similar?

Maaaybe.. but surely it would be easier to
just retrofit a normal ebb? I know this has
been done - it's just usually more trouble
than it's worth. Other than bike shop owners
and 60 y.o. mad bike builders with a large
stash of gear - I don't know anyone with all
the above parts/tools.

hippy
"Good luck!" ;-)

Hmm Mfhor - youv'e got far too much time on your hands!

Ok thanks all for the EBB size info - as I thought. A pain in the bum to fit, considering brazing isn't my fortay.

Hippy et al: Yup Eno is the answer. New rear wheel coming up.

Give me a week or so.. I think Cheeky Monkey has some in stock...

Tom