Loctite and mega exo bottom brackets

[[email protected]]

I have two questions about mega exo cranksets and bottom brackets I
didn't see answered on their web site, plus I am interesting in real
world bikeshop experience.

Q1. Loctite 641. A recent service bulletin says you need to use
Loctite 641 on the non drive side splines of carbon cranks. Where in
the hell can you find loctite 641? None of my local HW stores stock
it. Is there a suitable substitute, do you really need it?

Bulletin:
http://www.fullspeedahead.com/downloads/M-E installation bulletin 10-18-06.pdf

Q2. Italian threaded shells. My old (non external) dura-ace bottom
bracket had a lockring that would keep it from coming off the left
side. Are there any tricks to prevent this from happening on these
new external bearing bottom brackets? I would think they would slowly
loosen.

 

[Bob Flumere]

On 23 Feb 2007 10:23:44 -0800, "[email protected]" <[email protected]>
wrote:

>I have two questions about mega exo cranksets and bottom brackets I
>didn't see answered on their web site, plus I am interesting in real
>world bikeshop experience.
>
>Q1. Loctite 641. A recent service bulletin says you need to use
>Loctite 641 on the non drive side splines of carbon cranks. Where in
>the hell can you find loctite 641? None of my local HW stores stock
>it. Is there a suitable substitute, do you really need it?
>
>Bulletin:
>http://www.fullspeedahead.com/downloads/M-E installation bulletin 10-18-06.pdf
>
>Q2. Italian threaded shells. My old (non external) dura-ace bottom
>bracket had a lockring that would keep it from coming off the left
>side. Are there any tricks to prevent this from happening on these
>new external bearing bottom brackets? I would think they would slowly
>loosen.


Search here..

http://www.loctite.com/int_henkel/loctite_us/index.cfm?&pageid=19&layout=3

Loctite will sometimes send you a sample to try if ya call them..

Great products..

Bob

 

[jim beam]

[email protected] wrote:
> I have two questions about mega exo cranksets and bottom brackets I
> didn't see answered on their web site, plus I am interesting in real
> world bikeshop experience.
>
> Q1. Loctite 641. A recent service bulletin says you need to use
> Loctite 641 on the non drive side splines of carbon cranks. Where in
> the hell can you find loctite 641?

http://www.mcmaster.com/param/asp/p...sion=loctite_adhesives;2578=112118;2195=99910

> None of my local HW stores stock
> it. Is there a suitable substitute, do you really need it?
>
> Bulletin:
> http://www.fullspeedahead.com/downloads/M-E installation bulletin 10-18-06.pdf
>
> Q2. Italian threaded shells. My old (non external) dura-ace bottom
> bracket had a lockring that would keep it from coming off the left
> side. Are there any tricks to prevent this from happening on these
> new external bearing bottom brackets? I would think they would slowly
> loosen.

left side doesn't loosen. on italian, there's a theoretical loosening
movement on the right side, hence the loctite. but i've run italian
bb's for years over many many miles and i've never experienced it.

 

[Bruce Gilbert]

"jim beam" <[email protected]> wrote in message
news:[email protected]...
> [email protected] wrote:
> > I have two questions about mega exo cranksets and bottom brackets I
> > didn't see answered on their web site, plus I am interesting in real
> > world bikeshop experience.
> >
> > Q1. Loctite 641. A recent service bulletin says you need to use
> > Loctite 641 on the non drive side splines of carbon cranks. Where in
> > the hell can you find loctite 641?
>
>
http://www.mcmaster.com/param/asp/p...sion=loctite_adhesives;2578=112118;2195=99910
>
> > None of my local HW stores stock
> > it. Is there a suitable substitute, do you really need it?
> >
> > Bulletin:
> >
http://www.fullspeedahead.com/downloads/M-E installation bulletin 10-18-06.pdf
> >
> > Q2. Italian threaded shells. My old (non external) dura-ace bottom
> > bracket had a lockring that would keep it from coming off the left
> > side. Are there any tricks to prevent this from happening on these
> > new external bearing bottom brackets? I would think they would slowly
> > loosen.
>
> left side doesn't loosen. on italian, there's a theoretical loosening
> movement on the right side, hence the loctite. but i've run italian
> bb's for years over many many miles and i've never experienced it.

I have a 2000 Colnago Master Ex Light that kept having the right BB cup
loosen with a DA 9 speed BB. We finally set it in with some blue loctite. It
stayed in place for years. I believe it had something to do with how the BB
was prepped. It may have been done improperly, removing too much metal, as
the cup screwed in rather easily. Just a few months ago I decided to rebuild
the bike with some old 8 speed parts. I used an 8 speed DA BB and have not
experienced the loosening problem again. I did not use a thread locker, just
some grease this time. We'll see what happens.

Bruce

 

[Qui si parla Campagnolo]

On Feb 23, 11:23 am, "[email protected]" <[email protected]> wrote:
> I have two questions about mega exo cranksets and bottom brackets I
> didn't see answered on their web site, plus I am interesting in real
> world bikeshop experience.
>
> Q1. Loctite 641. A recent service bulletin says you need to use
> Loctite 641 on the non drive side splines of carbon cranks. Where in
> the hell can you find loctite 641? None of my local HW stores stock
> it. Is there a suitable substitute, do you really need it?
>
> Bulletin:http://www.fullspeedahead.com/downloads/M-E installation bulletin...
>
> Q2. Italian threaded shells. My old (non external) dura-ace bottom
> bracket had a lockring that would keep it from coming off the left
> side. Are there any tricks to prevent this from happening on these
> new external bearing bottom brackets? I would think they would slowly
> loosen.

Answer to Q1..don't use loctite on anything n a BB. grease and torque.

Answer to Q2...make sure the frame is prepped, faced and chased and
use a wee bit of teflon tape on the cups, along with grease and proper
torque.