Fixed gear via JB Weld and threadlocker



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E

Ed Cory

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Fools rush in, so I thought about it for a few days before I tried it.

I disassembled a 6 spd NOS Shimano freewheel, degreased and reassembled using JB Weld in place of
lube. I did NOT reinstall the ball bearings. I left the pawls and spring in, attempted to epoxy the
pawls into an interference position, I doubt that this succeeded.

I did not pay enough attention to aligning the two parts of the freewheel, there is misalignment
between the centers although the axes seems close to parallel.

Installed, there is no noticeable chain droop. Perhaps the eye is sensitive to errors which are too
small to matter.

I used red (permanent) threadlocker to attach the "used to freewheel" to the hub. Some rbt posters
say that interference friction is sufficient, I expect that the threadlock can only help.

The first test used 52:24 (cogs are 13-15-17-20-24-28). On a very hilly 7 mi loop considered
challenging by local runners, I ascended hills much faster than I would have thought possible.
This on a heavy 80's steel Bridgestone, compared to an all AL road bike where I would have
dropped to 30:23.

I did this ride unclipped due to my lack of fixed gear experience. I did pedal-brake to the best of
my ability. A stronger rider and/or more time will be a better durability test of this approach.

Switching to 52:20 (excellent chainline since my BB is a bit longer than the orig.) and spd pedals,
I moved to the nearby flatlands. After 12 miles of spinning for all I'm worth (my riding skills
rival my hack wrenching so I doubt that I averaged 100rpm) I turned around and discovered the wind
had been aiding.

After slogging along for 1/2mi, I stopped, gave thanks that Sheldon Brown's page had convinced me to
switch the solid axle to a steel QR and switched back to 52:24 for a slow but comfortable return
ride. This change was entirely accomodated by the horiz chainstays.

I plan to install 42t inside and 39t outside rings and hope that 42:20, 42:17, 39:17 and 39:15 will
be reachable without chain games. These would all be zero or one gear chainline "errors". The 52:24
(one gear error) is quiet and smooth- credit the SRAM PC-48? The 52 is a new "Rocket" ebay-ring with
no ramps nor pins.

Chain tensioning: lightly clamp the QR, crank a bit to allow the chain to slide the axle in the stay
a bit if needed, re-center the wheel if needed and clamp the QR tight to ride.

Thanks to Sheldon Brown in particular, and a few more
of you who were responsible for the inspiration. Ed
(remove spam to reply)
 
"David L. Johnson" <[email protected]> wrote in message news:<[email protected]>...
> On Sun, 08 Feb 2004 15:27:32 -0800, Ed Cory wrote:
>
> > I used red (permanent) threadlocker to attach the "used to freewheel" to the hub. Some rbt
> > posters say that interference friction is sufficient, I expect that the threadlock can
> > only help.
>
> I wonder how permanent "permanent" really is. What if you break a spoke?

<snip>

Permatex operating temperature tops out at 300deg F, they say to heat to 450 F to disassemble.
www.permatex.com/images/catalog/pdf/27100.pdf

This is less heat than the braze etc. approaches to "fixing" that have been suggested (less of a
threat to material properties) and should be reachable with a simple propane torch. This all seemed
desireable.

On the road is another matter, of course. Some excess cogs could be removed, grind off a little of
the freewheel to allow a re-dish so that the drive side spokes aren't as challenged. This is beyond
my current skillset.

JB Weld on a freehub body would seem to better support on the road spoke repair. Ed (remove
spam to reply)
 
On 9 Feb 2004 04:38:48 -0800, [email protected] (Ed Cory) said:

>
>On the road is another matter, of course. Some excess cogs could be removed, grind off a little of
>the freewheel to allow a re-dish so that the drive side spokes aren't as challenged. This is beyond
>my current skillset.
>
>JB Weld on a freehub body would seem to better support on the road spoke repair. Ed
>

What is the fascination with fixxes? I've ridden them and know what they're about but it seems that
if you have to jury rig something that might fail why the heck not just put a single speed freewheel
on and keep pedalling?

jeffb
 
> Chain tensioning: lightly clamp the QR, crank a bit to allow the chain to slide the axle in the
> stay a bit if needed, re-center the wheel if needed and clamp the QR tight to ride.

Do fixed gears always have a bolted axle? It seems this may be the exception. Do QRs not give enough
force to keep the axle static?

--
Phil, Squid-in-Training
 
Someone asked:
> Do fixed gears always have a bolted axle?

Definitely not. I generally recommend quick release for street use. That way you don't need to carry
a big wrench.

> Do QRs not give enough force to keep the axle static?

_Good Quality_ QRs give plenty of clamping force.

See: http://sheldonbrown.com/qr

Sheldon "Shish Kebab" Brown +---------------------------------------------------------+
| I don't like spinach, and I'm glad I don't, because | if I liked it I'd eat it, and I just hate
| it. | --Clarence Darrow |
+---------------------------------------------------------+ Harris Cyclery, West Newton,
Massachusetts Phone 617-244-9772 FAX 617-244-1041 http://harriscyclery.com Hard-to-find parts
shipped Worldwide http://captainbike.com http://sheldonbrown.com
 
I'm not sure I get it. Why would this be a viable option over just using a regular cheap track cog?
Seems like a lot more work. Not to mention the risk of unscrewing during braking.

Some years back, I made a one-speed of my workbike after the derailer accidentally got trashed, by
simply removing it and cropping the chain. The chainline worked out to a decent all-round ratio and
I ended up leaving it that way for a year. Had I made it into a quick and dirty fixer without a
lockring of some kind, I probably would have kept both brakes and not done too much pedal braking.
 
Ed Cory <[email protected]> wrote:

> > > I used red (permanent) threadlocker to attach the "used to freewheel" to the hub. Some rbt
> > > posters say that interference friction is sufficient, I expect that the threadlock can only
> > > help.

> > I wonder how permanent "permanent" really is. What if you break a spoke?

> Permatex operating temperature tops out at 300deg F, they say to heat to 450 F to disassemble.
> www.permatex.com/images/catalog/pdf/27100.pdf

> This is less heat than the braze etc. approaches to "fixing" that have been suggested (less of a
> threat to material properties) and should be reachable with a simple propane torch. This all
> seemed desireable.

> On the road is another matter, of course.

Interesting experiment. If you still have caliper brakes on the bike, you may never backpedal hard
enough to bust a track cog or immobilized freewheel loose, assuming it is installed with a
chainwhip or large wrench; red Loctite is overkill. I suspect Blue Loctite would be somewhat more
optimal than red - you could then probably still remove the cogs with a freewheel remover and big
wrench to do repairs.

Leaving a few of the bearings in would have helped get the halves of the freewheel aligned.
Something to remember for the second time.

> I plan to install 42t inside and 39t outside rings and hope that 42:20, 42:17, 39:17 and 39:15
> will be reachable without chain games.

The ring/cog combinations you can use are governed by the length of your dropout. For a given chain
length, each additional tooth in the sum of chain+cog moves the axle forward by 1/8 inch. I doubt
that you'll be able to use both 42:20 and 39:15 unless the bike has really long dropouts. You could
use a Powerlink and carry a one-link piece with a second Powerlink.
 
On 9 Feb 2004 16:56:08 -0800, [email protected] (papercut) wrote:
>I'm not sure I get it. Why would this be a viable option over just using a regular cheap track cog?
>Seems like a lot more work. Not to mention the risk of unscrewing during braking.

1. Fixed on the ultra-cheap
2. Do it entirely with stuff you've already got
3. Do it today, don't wait for mail-order parts or buy expensive locally
4. Some of us just have bloody weird minds that insist on doing it this way

I, personally, have considered that exact plan, and intend to implement it someday (soon?). This
report is encouraging.
--
Rick Onanian
 
>>Chain tensioning: lightly clamp the QR, crank a bit to allow the chain to slide the axle in the
>>stay a bit if needed, re-center the wheel if needed and clamp the QR tight to ride.

Signore Calamari wrote:
> Do fixed gears always have a bolted axle? It seems this may be the exception. Do QRs not give
> enough force to keep the axle static?

A reasonably good skewer clamps more tightly than a nutted axle. (My own fixed has never slipped)

--
Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971
 
Benjamin Weiner <[email protected]> wrote in message news:<4028389c$1@darkstar>...
> Ed Cory <[email protected]> wrote:

<snip>

> Interesting experiment. If you still have caliper brakes on the bike, you may never backpedal hard
> enough to bust a track cog or immobilized freewheel loose, assuming it is installed with a
> chainwhip or large wrench; red Loctite is overkill. I suspect Blue Loctite would be somewhat more
> optimal than red - you could then probably still remove the cogs with a freewheel remover and big
> wrench to do repairs.

I considered the backpedaling part of the desired training effect - it seems to correspond to the
eccentric contraction in body-builder/ exercise phys. talk and downhill running. I tried to maximize
my backpedaling after I became somewhat confident that it was holding together fine.

Yes, I have brakes on it and definitely used them. Downhill on my first fixed-gear outing, un-
clipped, I would have been out of control without them.

The torque specs seem to offer little advantage for the red over blue. I was hedging (my health)
that there was some strength/durability advantage to the red.

A chain whip would also give big torque on the used-to freewheel. Advantageous for those who stay
with a solid axle.

> Leaving a few of the bearings in would have helped get the halves of the freewheel aligned.
> Something to remember for the second time.

I mentioned it for the benefit of those who follow. I suspect that the JBWeld would fill the larger
gap without loss of assembly strength, but I plead ignorance.

> > I plan to install 42t inside and 39t outside rings and hope that 42:20, 42:17, 39:17 and 39:15
> > will be reachable without chain games.
>
> The ring/cog combinations you can use are governed by the length of your dropout. For a given
> chain length, each additional tooth in the sum of chain+cog moves the axle forward by 1/8 inch. I
> doubt that you'll be able to use both 42:20 and 39:15 unless the bike has really long dropouts.
> You could use a Powerlink and carry a one-link piece with a second Powerlink.

1/8 inch seems to match the 1/2" shift in the stay I got between
2:20 (mid-dropout) and 52:24 (the end). Maybe I remember reading this on one of Sheldon
Brown's pages(?).

Thank-you for pointing toward the error in my post: the plan is 39t in 42t out (reversed in the orig
post) for 39:20, 39:17, 42:17, 42:15 which is only a three tooth difference min-max and gives a
wider gear-inch range. (Is this an example of lexdysia?)

3:13 would be two more teeth, and another gear's chainline error but could fit within the about an
inch long stays. This will be tried purely out of curiousity, I'm not that strong or fast.

I hedge on the fit because adjusting the chain for the min-tooth count case can make very
significant dropout unusable for the "shifting" purpose. My 52:20 may have been about worst case. I
could also learn more about "half" links... Ed (remove spam to reply)
 
"Ed Cory" <[email protected]> wrote in message
news:[email protected]...
> Benjamin Weiner <[email protected]> wrote in message
news:<4028389c$1@darkstar>...
> > Ed Cory <[email protected]> wrote:
>
> <snip>
>
> > Interesting experiment. If you still have caliper brakes on the bike, you may never backpedal
> > hard enough to bust a track cog or immobilized freewheel loose, assuming it is installed with a
> > chainwhip or large wrench; red Loctite is overkill. I suspect Blue Loctite would be somewhat
> > more optimal than red - you could then probably still remove the cogs with a freewheel remover
> > and big wrench to do repairs.
>
> I considered the backpedaling part of the desired training effect - it seems to correspond to the
> eccentric contraction in body-builder/ exercise phys. talk and downhill running. I tried to
> maximize my backpedaling after I became somewhat confident that it was holding together fine.
>
> Yes, I have brakes on it and definitely used them. Downhill on my first fixed-gear outing, un-
> clipped, I would have been out of control without them.
>
> The torque specs seem to offer little advantage for the red over blue. I was hedging (my health)
> that there was some strength/durability advantage to the red.
>

Red's fine. It's just a little more work getting things off with red. I have both red and blue, I
use red on things I won't be removing for awhile.

Greg
 
In <[email protected]>,
"David L. Johnson" <[email protected]> opined:

> I wonder how permanent "permanent" really is.

Permatex "Permanent Red" lists a typical breakaway strength of 189 inch-pounds. It's also
inappropriate for > 1 inch diameter applications.

http://www.permatex.com/MSDS_data/tds_industrial/26250.pdf

Park's torque table lists "Cassette sprocket lockring" torque recommendations from 260 - 434 inch-
pounds, depending.

http://www.parktool.com/repair_help/torque.shtml

I gotta wonder - if a lock ring that sees hardly any reverse torque needs at least 260 inch-pounds
of torque, just how much torque resistance could be enough for a fixed gear setup?

Seems like 250 inch-pounds is not quite there.

(Hey - the same search that found this also unearthed the interesting tidbit that torque set "by
feel" is +/- 35% of target, while torque wrenches are +/- 25%. Better, but not a whole lot...)

--
Dave Salovesh [email protected] (REPLACE example WITH mindspring TO EMAIL ME)
 
Dave Salovesh wrote:
> In <[email protected]>, "David L. Johnson"
> <[email protected]> opined:
>
>>I wonder how permanent "permanent" really is.

Dave Salovesh wrote:

> Permatex "Permanent Red" lists a typical breakaway strength of 189 inch-pounds.
> http://www.permatex.com/MSDS_data/tds_industrial/26250.pdf

That's for a 3/8" bolt. Multiply it by 2.7 for the 1 3/8" diameter of a standard sprocket thread.

The spec doesn't mention the depth of thread engagement involved, just says a standard 3/8 - 16 nut,
which is probably a bit thicker than a typical track sprocket.

Not sure what effect the much narrower thread pitch would have.

I've used blue loctite and never had a sprocket unscrew, but I don't run very low gears except on my
snow bike.

> (Hey - the same search that found this also unearthed the interesting tidbit that torque set "by
> feel" is +/- 35% of target, while torque wrenches are +/- 25%. Better, but not a whole lot...)
>
That's why you need a tool with Real World (TM) calibrations, viz:

http://sheldonbrown.com/tork-grip.html

Sheldon "Tork-Grip" Brown +--------------------------------------------------------+
| As far as the laws of mathematics refer to reality, | they are not certain; and as far as they
| are certain, | they do not refer to reality. --Albert Einstein |
+--------------------------------------------------------+ Harris Cyclery, West Newton,
Massachusetts Phone 617-244-9772 FAX 617-244-1041 http://harriscyclery.com Hard-to-find parts
shipped Worldwide http://captainbike.com http://sheldonbrown.com
 
Just got to watch the pedal strke on those tight steep twisties with a fixed. I've been taking those
tight turns a little wide on the climbs. As far as descending, It's better to freewheel and save
your legs. -tom

> On 10 Feb 2004 14:04:00 GMT, [email protected] (Qui si parla Campagnolo) said:
>
>
> >'keep pedaling' is the fascination, whether up or down, making one get
training
> >in a shorter amount of time, teach one to climb and decend well...
 
jeffbonny <[email protected]> wrote:
: No ****. You can't do that on a SS freewheel? Spinning is spinning and if you don't have the skill
: or the will to spin getting yer legs dragged around by a fix is a waste of time.

modulating (i don't necessarily mean braking) your speed by either direct back pedaling or leg drag
is pretty nice, track standing is a lot easier and a whole lot more fun if you can actually pedal
backwards (or more to the point put pressure on the rearward pedal) and of course just plain riding
backwards. i've grown to like the feel, as well, even if i'm just getting dragged along. a freewheel
would take away from the experience.

: What I didn't get (and still don't) is why anyone (see this and other recent threads) would think
: the benefits of a fix are worth the risks of a jury rigged system. They aren't.

i'm with you on that. i like my lockring even if i could get away with not having one.
--
david reuteler [email protected]
 
jeffbonny wrote:

> ...I understand why people ride fixxes, I was one for several years with a Dura-ace track hub.
> What I didn't get (and still don't) is why anyone (see this and other recent threads) would think
> the benefits of a fix are worth the risks of a jury rigged system. They aren't.

What "risks" do you suppose there are with such a system? I don't see a safety issue with this,
worst case would be the need to walk home.

I certainly promote the use of gen-you-whine track hubs--after all, I sell skillions of them, but I
also urge impecuinous but ingenious cyclists to give fixed gear a try whatever way works for them.

http://sheldonbrown.com/fixed

Sheldon "Keep Pedaling" Brown +------------------------------------------+
| To invent, you need a good imagination | and a pile of junk. --Thomas Edison |
+------------------------------------------+ Harris Cyclery, West Newton, Massachusetts Phone 617-244-
9772 FAX 617-244-1041 http://harriscyclery.com Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com
 
On Tue, 10 Feb 2004 17:30:22 -0500, Sheldon Brown
<[email protected]> said:

>What "risks" do you suppose there are with such a system? I don't see a safety issue with this,
>worst case would be the need to walk home.

A winter walk in a pair of wood soled Duegis might be hazardous to yer health... And what about
nutting yerself? Ow.

OK, I guess I wasn't giving credit where it was due. I was thinking about the morons riding
fixes without adequate braking systems who rely overmuch on the cog _remaining_ fixed. That
could be risky.

>I certainly promote the use of gen-you-whine track hubs--after all, I sell skillions of them, but I
>also urge impecuinous but ingenious cyclists to give fixed gear a try whatever way works for them.

If it works then it's right.

jeffb
 
On Tue, 10 Feb 2004 17:30:22 -0500, Sheldon Brown
<[email protected]> wrote:
>| To invent, you need a good imagination | and a pile of junk. --Thomas Edison |

To lament, that quote leaves exasperation because it is bunk. --Rick "Never invents anything
good" Onanian
 
On Tue, 10 Feb 2004 15:12:43 -0500, Sheldon Brown
<[email protected]> wrote:
>That's why you need a tool with Real World (TM) calibrations, viz: http://sheldonbrown.com/tork-
>grip.html

The calibrations shown on it's gauge do not include anything I can relate to except for stripped (my
most common torque spec); why not have it on the female celebrity scale?

I will refrain from using my opinions to create this scale, but maybe something like (guessing from
various bits of subculture here): Mary Kate Olsen Stripped Lucy Liu Angelina Jolie Pamela Anderson
Madonna Courtney Love Janet Jackson Courtney Love Madonna Pamela Anderson Angelina Jolie Lucy Liu
Stripped Ashley Olsen
--
Rick "Sick" Onanian
 
On Tue, 10 Feb 2004 22:24:24 -0500, "David L. Johnson"
<[email protected]> wrote:
>Ok, leaving aside the comparison of the various people you listed, or how they rate their relative
>positions on the scale, I gotta know. I recognized the names, except this one. Who or what is a
>Mary Kate Olsen?

She, and her identical twin sister Ashley, are tv / movie stars. I

about them, although I don't recall where (maybe a radio DJ or something).
--
Rick Onanian
 
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