Wednesday, April 16, 2008

Crank Brothers Eggbeater servicing II



A follow up to an earlier post, Crank Brothers Eggbeater servicing.



Another quarter, another round of Eggbeater servicing.
Left to right: SL, 3Ti, and 4Ti.
The stainless steel M5 (thread) 8 mm (socket diameter) nylon locking nuts are replacements. At 10 cents each, it's a no-brainer for added security.





How to unscrew the spindle nut when the pedal is not attached to a crank arm. On the crank arm side, an 8 mm hex bit (6 mm for some) holds the spindle, while on the pedal body end, an 8 mm socket unscrews the nut. All the spindle tips are threaded in the regular fashion. I.e. counter-clockwise unscrews. It shouldn't take much force to remove the nut as it is only torqued to 30 inch-pounds.

From here, the rest of the steps are identical to the earlier post, Crank Brothers Eggbeater servicing. What the rest of this post consists of, are general observations between the 3 pairs of pedals, as well as maintenance steps which go beyond the first post.





Spindles, left to right: 4Ti, 3Ti, SL.
The 2 on the left, as their namesakes imply, are made of 6AL-4V titanium, while the SL is made of forged 420 stainless steel. The gold finish is a nitride coating. It is interesting to note that the 3Ti spindle only received a partial nitride coating. A later incarnation of the Eggbeater, the 4Ti spindle is 4mm shorter than the rest, yielding a lower Q-factor. These shorter spindles, of both the titanium and stainless steel variants, are now available.

The SL spindle is rather hefty and inspires confidence. As for the titanium spindles, Crank Brothers recommends a maximum rider weight of 85 kg (185 lb). IMHO, if you are anywhere near 80 kg (176 lb), and carry a Camelbak or a backpack, I would stick to the SL.

Then again, eunuchs could be the next fashionable (repressed / harassed) minority for the jaded-languorous-and-disaffected masses to protest, petition, and picket for when their organic, sustainably-sourced, non-fat, no whipped cream, soy milk lattes (brewed from coffee beans lovingly massaged between the thighs of young ex-Soviet virgins) run out at home-owned cafes... So what do I know? Maybe it will kick-start a new trend. After the 2008 Olympics are over, indignant, self-righteous, overly-bored, whiny Luddite protesters do need something to snatch. Condoms are as good as any. Go for it.  :-P





Interestingly, the 4Ti and SL Eggbeaters come with Enduro cartridge bearings, which have removable seals, while the 3Ti pedals come with Kako cartridge bearings, with permanent shields. Both types of cartridge bearings possess the same dimensions.


Eggbeater spindle cartridge bearings

Outer diameter:  6 mm
Inner diameter:  13 mm


Enduro
686LLU
metal-backed silicon dust seals
serviceable

Kako - Japan
6867
pressed fit metal dust shield
non-serviceable





Slipping a pin from the inside of the Enduro bearing easily pops the seals off. The Kako bearing can only gaze on in envy. AA battery present for a sense of scale.

The silicone seals must not be washed with degreaser as it wrinkles them. Use dishwashing liquid instead.

The cartridge bearing is fully metal, including the cage, so it is safe to use degreaser on it. An old toothbrush speeds things up.





After everything is dry, a grease gun makes short work of repacking the bearing with grease. I like FinishLine's Premium Grease. Phil Wood's Waterproof Grease or Enduro's Super-Web Grease are also great choices.




DISCLAIMER

What follows goes beyond the pedal rebuild process. Crank Brothers explicitly cautions against this:

Do not try to disassemble the Body Assembly because special tools are required for re-assembly.

Please do not attempt the following if you are not confident of putting the pedal back together again. Instructions are not provided. If you can't figure it out, then you should not be attempting this.



Eggbeater stripped. It is amazing how simple it is.

Left to right:
(pedal) body
spring
(pedal) wings
spindle
spindle sleeve
spindle sleeve o-rings (2)
(threaded) dust cap
dust cap o-ring
spindle cartridge bearing
spindle nut

14 parts.

Dust cap O-ring
Internal diameter:  12.8 mm
Width:  1 mm

Note: there is an earlier version of the Eggbeater with non-threaded dust caps. Unfortunately, I have no information on this.

The pedal body (big chunk of metal on the extreme left) has an ingus composite bushing and a reinforced lip seal pressed into it. Both are supplied in the Pedal Rebuild Kit.





As the SL Eggbeater is my workhorse, the spindle sleeve on it fared the worst. The broad upper and lower bands of wear, caused by the pedal wings when ever I clip in or clip out, did not pose any problems during disassembly. The narrow, middle bands in the middle, etched by the spring, did. The harder, 300 series stainless steel, spring wore deeply into the sleeve, rendering removal of the sleeve a frustrating operation.

O-ring groove diameters

Outboard end (wider):  10 mm
Inboard end (narrower):  9.6 mm





This, IMHO, is the Achilles' heel of the Eggbeater. The O-rings on the spindle sleeves get chewed up. Water, grit, Mas Selamat bin Kastari, and dust then sneak in, contaminating the grease which lubricate and protect the spindle bushings, as well as soaking the cartridge bearing. Thus, leading to a premature rebuild.

Despite apparent appearances, the 2 O-rings on the sleeve are not identical.

Upper O-ring
Internal diameter:  10.3 mm
Width:  1 mm

Lower O-ring
Internal diameter:  9.3 mm
Width:  0.9 mm

Swap them around and it would be next to impossible to reassemble the pedal.





Pedals serviced.

Note the composite dust cap on the SL pedal (left). It doesn't seal against the elements as well as the alloy dust caps with O-rings. Handicapping what is essentially a very robust pedal (more robust than the titanium variants) is silly, IMHO.

Another weak point of the Eggbeaters is that the left (or non-drive side) pedal spindle tip is not reverse-threaded like the spindle. This essentially means that, should the cartridge bearing ever seize, the spindle nut would unscrew during pedaling and the pedal body would detach from the spindle — possibly leading to a loss of control. This compromise in reliability is a real concern for tourers.

That said, I still love the Eggbeaters for their mud-shedding design, mechanical simplicity, light weight, and — possibly — thief-deterring micro-platform. I.e. most people would find it a daunting endeavor to hop on to a bike with Eggbeaters on sneakers (or worse, flip-flops) and take off sprinting  :-P

15 comments:

Anonymous said...

Great write up dude!!

Henrik Moltke said...

"should the cartridge bearing ever seize, the spindle nut would unscrew during pedaling and the pedal body would detach from the spindle — possibly leading to a loss of control. This compromise in reliability is a real concern for tourers".

Wow. This is exactly what happened to my 1 ti´es - I heard a strange sound which I mistook for dirt / grit caught between clamp and pedal, got up standing to clear a small, muddy hill, and next thing I was lying on the ground with the body on my shoe, spindle on the bike.

-ben said...

Thanks, Jimmmy :-D

------

Henrik,

Ouch!
Hope you are all right.

That said, the Eggbeaters are very robust (apart from this very serious fault) -- I took the 4Ti on a 2-week off-road tour, lugging 51.7 kg (114 lbs) of gear, including a trailer, and crashed the bike heavily on hardpack, rocks, and gravel countless times. Amazingly, they held up fine. (Probably needs a relubing now though.)

I don't understand why Crank Brothers won't reverse the thread on the non-drive side spindles. It is not even a redesign, just new dies to cut the thread. Bottom brackets, pedal spindles are done this way. It makes no sense not to follow convention here.

Cheers.

Anonymous said...

Nice piece. I did you replace the spindle sleeves, and if so are they easily available?

Thanks

-ben said...

Thanks :-)

No, the spindle sleeves were not replaced. And they are not available in the rebuild kit. I have no idea if Crank Brothers entertain such requests :-(

Note: if removing (heavily) scored spindle sleeves is difficult -- stop. You may find re-inserting them impossible later.

Anonymous said...

Wow, tons of info, gonna get locking bolts tomorrow!

Thanks!

Ahmed said...

Hello Ben,

The situation here is that.

I got the body of the bearing on my eggbeater body stucked. All of the balls and seals are tooked out. Made a mistake there.

Care to explain more on how to dissamble the Body?

Seems like it is the only way i can think of getting the bearing body out.

Hope you can help me ^.^

Regards,
Ahmed.

-ben said...

Hi Ahmed,

I'm sorry you ran into difficulties with your eggbeaters.

Can you clarify what is stuck?

The cartridge bearing has a press-fit bearing cage. How did you manage to remove the balls from the cartridge bearing without removing the cartridge from the pedal body?

As for disassembling the body, the body only comes apart when the wings are flexed to reduce spring tension and then the sleeve pushed out from the inboard side. If the bearing is stuck in the pedal body, there's no way you can accomplish that.

Can you clarify your present situation with the cartridge bearing body?

If it is indeed stuck, perhaps a bamboo chopstick and a rubber mallet might help in gently taping it out. Do not use a screwdriver or metal as it would damage surfaces. Do a to-and-fro motion to slowly rock the cartridge bearing out. Don't force as the bearing body is harder than the pedal body.

I would advise against disassembling the pedal body as it is quite tricky to get it back again.

Good luck!

AhmdShah said...

http://farm3.static.flickr.com/2655/4192569995_de25464cec_o.jpg

AhmdShah said...

Hello ben, thanks for the reply, i think my reply havent been sent yet, i didnt do the word verification, well if it havent. This is another one for you, explaining on the situation.

At first, i was trying to pull out the bearings, i was trying soo hard that only the seal and the balls came out.

For the other side of the pedal, i did push, it came out easily, what a bummer.

*sighs* hope you can help me out with this one.

Is there any way i can open up the body with the cartridge is still in?

Thanks Ben! :D

-ben said...

Hi Ahmed,

Oh crap! Looks like you pulled a little too hard there :-(

So, to confirm, you managed to remove the INNER race, the 2 seals, the ball-bearing retainer / cage, and the balls. Yes?

So all that's left is the OUTER race then. Yes?

You see, the sleeve sits like a "T" in the pedal body. Your OUTER race is sitting on the top of the "T" now. Without the entire bearing coming out (that includes the OUTER RACE), the sleeve cannot come out. If the sleeve cannot come out, then the pedal body cannot be disassembled. You get the picture?

The way to get the cartridge bearing out was to use a piece of wood (e.g. chopstick) and gently tap it out. The cartridge can get caught on the threads (as you can see in your picture) so some back and forth finesse -- AND LOTS OF PATIENCE -- is required here.

BUT, that only works if the cartridge bearing is complete as you can only reach the lip of the INNER race.

I am not quite sure what to do at this point so the following are only suggestions:

1.) Use a rubber mallet or plastic hammer and bamboo chopstick and gently tap the inner seal back in, and see if it "unjams." If it works, then use some L-shaped metal tool and patiently rock back and forth to get it out. Be careful and do not scratch the inside of the pedal body.

2.) In my opinion, pushing through from the OTHER (inboard) side as you suggested will be very hard or near impossible. To do that, you will have to remove or sacrifice the lip seals and bushings. But, since your cartridge bearing is already toast, you need a rebuild kit anyway (Rebuild kits come with all that). But the operation will require A LOT OF FORCE -- the "T" head of the sleeve is quite soft -- and you might very well destroy the pedal.

3.) If you have access to a machine shop or an automotive shop, try and see if they have a lip puller, or gear puller that is small enough, and see if they can use that. That's the least damaging.

The race is VERY HARD, so I don't see how you can bend or break it inside the softer pedal body to remove it.

4.) The last resort will be to return to Crank Brothers for servicing. It might be worth this route if you have a local dealer. The last thing you want to do is to hurt yourself or destroy more parts. The pedal sleeve, for example, is not part of the rebuild kit.

I will post more if I think of anything.

Please wear eye protection and good luck!

0_o

AhmdShah said...

Thanks Ben. That really helps.

I'll give it a try later. Still stucked with other works. Hehe.

I do, and really, get the picture that. Bearing not out of the pedal body = No dissembling of the body.

Hehe. Thanks! :) will wear one!

Unknown said...

Thanks for the info. I always have maintained my pedals but crank bros always made me send them the pedals to change out the cage. But I just did this myself and it was really easy. I found a used set of candy's which were almost new for $15, and swapped out the cage onto my mallet C's and they are like new now! Sweet!

Unknown said...

Do you know the inner size of the 8mm nut?
Thaks

-ben said...

Hi jcallero,

If memory serves, I am quite certain it is 4 mm. (I remember the spare nuts listed as "M4 nuts.")

Hope that helps!

:-)