BB Questions

Fujiman said:

Installing FSA SLK Carbon crank set and the left crank arm will not go all the way on the splines of the spindle? so I have a gap between the arm and the BB cup, BB is Megaexo I would assume the arm should go all the way on the splines? I am really frustrated!!!
Also does anyone know what the Green piece that looks like a cup or possible shim is for? It came in the box with the crankset.

There should NOT be any gap to speak of ... maybe a HALF of a millimeter!

I don't want to state what may/should be obvious, but you have to loosen BOTH bolts on the end of the non-driveside crank arm. I can't imagine another reason why the arm wouldn't go all the way onto the spindle ... but, maybe I don't know what your idea of a gap is ...

[center]Is the gap significantly MORE than the thickness of an envelope?[/center]

That green "cup" has no known (to me) value ... and, someone else will have to tell you why they include it -- the only thing I can imagine, which is NOT advised, is if you were to set the frame on its side while pressing the driveside into the BB then you would set the non-driveside cup into the green plastic cup while it is on the "ground" ... BUT, it really shouldn't take that so much effort to slide the spindle into the BB that you would need/want to lay the bike on its side.

alfeng said:

There should NOT be any gap to speak of ... maybe a HALF of a millimeter!

I don't want to state what may/should be obvious, but you have to loosen BOTH bolts on the end of the non-driveside crank arm. I can't imagine another reason why the arm wouldn't go all the way onto the spindle ... but, maybe I don't know what your idea of a gap is ...

[center]Is the gap significantly MORE than the thickness of an envelope?[/center]

That green "cup" has no known (to me) value ... and, someone else will have to tell you why they include it -- the only thing I can imagine, which is NOT advised, is if you were to set the frame on its side while pressing the driveside into the BB then you would set the non-driveside cup into the green plastic cup while it is on the "ground" ... BUT, it really shouldn't take that so much effort to slide the spindle into the BB that you would need/want to lay the bike on its side.

The non-drive side crank arm does not have 2 bolts, like my omega the slk has a splined insert that slides over the spindle then a retaining bolt that holds the arm on.

Fujiman said:

The non-drive side crank arm does not have 2 bolts, like my omega the slk has a splined insert that slides over the spindle then a retaining bolt that holds the arm on.

Of course, sorry ...

Regardless, there shouldn't be very much (if any!) space between the non-driveside arm & the BB cup.

Just how much of a gap is there?

This may NOT be applicable, but can you slide the arm on inside-out (the way you can with an alloy arm) so you can check to see if there are any obstructions in the receiving grooves for the splines which are not obvious when you put the arm on the right way, or do the receiving grooves stop before reaching the outer end of the insert in the arm?

typical garbage advice alfeng of stuff you have never used and never set your hands upon.

the 'green disc' is a shell spacer. it goes between the left cup and the bb shell. if you install this it'll remove the gap that you have noted. some frames require the spacer, some don't. some need the spacer to fit the center sleeve, but then you can't fit the arm properly without removing eithe one or both of the blue seal washers.

personally i use shimano cups on one bike, simply because at the time FSA in italian weren't widely available. it doesn't require the spacer. i use an FSA on another bike that does need it, it looked [censored] (being bright green and all), so i substituted in a black spacer from shimano mtb cups which works just fine.

--brett

sideshow_bob said:

typical garbage advice alfeng of stuff you have never used and never set your hands upon.

Right, the only carbon crank I have is an old ISIS crank ... but, I have several MegaExo & Hollowtech II cranks.

sideshow_bob said:

the 'green disc' is a shell spacer. it goes between the left cup and the bb shell. if you install this it'll remove the gap that you have noted. some frames require the spacer, some don't. some need the spacer to fit the center sleeve, but then you can't fit the arm properly without removing eithe one or both of the blue seal washers.

You've got to be kidding with regard to sleeving the 'green cup' over the BB to make up the gap ... its much more than 2mm thick between the inside face & the outside face.

There's no way that 'green cup' that FSA includes will sleeve over a BB shell, regardless ... the 'green disc' you/(Brett) are referring to is not what Fujiman was referring to.

BTW. If you only put a spacer on the non-drive side of an external bearing BB, then the crank arms will not be equidistant from the centerline of the bike since you will more-than-likely be bumping the non-driveside crankarm out by whatever the thickness of the spacer is.

alfeng said:

You've got to be kidding with regard to sleeving the 'green cup' over the BB to make up the gap ... its much more than 2mm thick between the inside face & the outside face.

the plastic disc goes over the threads of the cup and fits flush between the inside wall of the cup and the shell face.

http://road.fullspeedahead.com/downloadfly.aspx?download=downloads/Install_MegaExoCarbon.pdf

Page 3, look at the 'road' image. Part 5, install the rubber shell spacer.

Do you see one on the drive side?

Quoted post said:

BTW. If you only put a spacer on the non-drive side of an external bearing BB, then the crank arms will not be equidistant from the centerline of the bike since you will more-than-likely be bumping the non-driveside crankarm out by whatever the thickness of the spacer is.

it's 1.5 mm give or take. you don't notice the any difference.

shimano mtb cups require 2 spacers on non-drive, 1 on the non-drive. again makes no difference.

--brett

sideshow_bob said:

--brett

You're working WAY TOO HARD to justify your earlier mis-reading of the OP's query about the 'green cup' ...

You gladly nitpick my remakrs, so shouldn't you anticipate reciprocal scrutiny for what you say?

Tsk. Tsk.

Go find Swansong (sic) & have a pajama party, or something.

alfeng said:

You're working WAY TOO HARD to justify your earlier mis-reading of the OP's query about the 'green cup' ...

ha ha ha ... you've been called out again for bullshitting the forum alfeng and here come the hysterics.

it's really a bit of a no brainer, but unsurprisingly a guy who seems to know better than the engineering teams of campag, sram etc etc can't figure it out.

here i'll give you the remedial version. crank is not going all the way down the spline, cause the bolt is bottoming out. it means the spindle is too long, it's shortened relative to the bottom bracket by making the bottom bracket wider. you make it wider by installing (as per the manufacturers instructions) the green plastic washer between the shell face and the cup.

why is this required? probably so they only have to make one spindle length for both english and italian bb's. remarkably the spacer is right about the same thickness as the difference between 68 and 70mm.

you can now go and have a good lie down alf.

-brett

sideshow_bob said:

ha ha ha ... you've been called out again for bullshitting the forum alfeng and here come the hysterics.

it's really a bit of a no brainer, but unsurprisingly a guy who seems to know better than the engineering teams of campag, sram etc etc can't figure it out.

here i'll give you the remedial version. crank is not going all the way down the spline, cause the bolt is bottoming out. it means the spindle is too long, it's shortened relative to the bottom bracket by making the bottom bracket wider. you make it wider by installing (as per the manufacturers instructions) the green plastic washer between the shell face and the cup.

why is this required? probably so they only have to make one spindle length for both english and italian bb's. remarkably the spacer is right about the same thickness as the difference between 68 and 70mm.

you can now go and have a good lie down alf.

-brett

You know, if you (or, others) want to continue to embrace SRAM's shifters, well good-on-yah ... as I said before, SRAM knew it was a flawed design when the started to market it, as witnessed by the introduction of the RED group ... but, for those who wanted to, or continue to want to pay a premium for it, so be it. Conspicuous consumption certainly has its place in the cycling world as well as in other walks of life.

Didn't SRAM also abandon the GXP BB with the RED group, too?!?

Gears-are-gears, and any gear can be stripped under the wrong circumstances ... a small number of people have apparently had problems with their UT cranks which may be unrelated to the Hirth coupling, so it isn't quite as perfect as you would like to think, regardless.

Since you still don't know OR want to admit what "dwell" is in Shimano shifters, there's not much to say about it. But, if you manage to use the Forum's search, you will see that the work-around is to pre-shift before going uphill OR to dump onto a granny ... of course, for Flatlanders, it isn't a factor.

I seriously doubt that Shimano's electronic shifters continue to incorporate "dwell" ... but, who knows? "Why fix an obvious problem?" is clearly your motto, and may be their's.

Believe-it-or-not, you don't have to know more than the engineers who design something to be able to recognize when there is what is apparently an "acceptable flaw" in the design.

You do have to be a poor consumer if you think that just because you're paying a pretty penny for something that it is always going to be designed well. No doubt, a bean-counters decision which the marketing department is told to [censored] consumers like you ...

Oh, did you buy your SRAM Rival/Force shifters, already?

How are they working out for you?

OR, is SRAM going to manage to double-tap your wallet when you realize that you need the RED shifters to have truly acceptable, better-than-recreational performance?!?

BTW. In case you haven't noticed, the OP still hasn't stated what the gap differential is ...

FYI. I have an Ultegra Hollowtech II triple crank, and it has a "spacer" for the non-drive side ... but, thanks for the tip.

Now, go add some spacers to any of your non-SLK crank's non-drive side so you can have the same asymmetry on all your cranksets OR go play with your buddies, but stay out of the middle of the road ... OR, was there anything else you wanted to say right now?

ha ha ha ... keep ranting alf. maybe you could call up SRAM, then Campag, then Shimano tell them how stupid all their R&D teams are and see if they'll hire you. At least you know you're smarter than the lot of them.

RED didn't replace Force btw, they are simply different price points. But then again it's probably a bit too simple of a concept for you to understand.

I did play in the road today, a little over 100km on a Force equipped bike no less. Shifts perfectly, go figure.

--brett

sideshow_bob said:

ha ha ha ... keep ranting alf. maybe you could call up SRAM, then Campag, then Shimano tell them how stupid all their R&D teams are and see if they'll hire you. At least you know you're smarter than the lot of them.

RED didn't replace Force btw, they are simply different price points. But then again it's probably a bit too simple of a concept for you to understand.

I did play in the road today, a little over 100km on a Force equipped bike no less. Shifts perfectly, go figure.

--brett

My bad -- I do know that the Rival/Force groups are still out there (SRAM is dumping them on the OEM market of American branded bike manufacturers), but I didn't want to use the word "supersede" because I didn't know if you would know what that means.

You do realize that the mechanism for the RED group is different, don't you? It is more than just a price-point difference.

You do know that the RED group has replaced the Rival/Force groups for professional Tour teams, don't you?

Yeah, SRAM is probably going to double-tap your wallet at some point in the future ... how sweet is that going to be for them?!?

Don't fret ... I don't want to have the last laugh ... but, I have little doubt that SRAM wants to have it. So, keep laughing with your "ha ha ha" until they do.

BTW. I don't need to tell the respective engineering groups what may be wrong with their components ... just because YOU don't know what may be wrong in a design doesn't mean that THEY don't already know OR that people outside the engineering groups can't discern what may be wrong ... it IS often, as I mentioned, a matter of the bean-counters stopping the R&D and trotting things out to the market place -- it's the way of the Capitalistic world. I didn't think it was too difficult a concept to grasp that my lack of fawning acceptance over either a "new" or accepted design wasn't an inference that I know better ... but, apparently it continues to be too difficult a concept for you to grasp.

woo hoo ... thread has successfully been turned into frothing and foaming alfeng sram rant fest.

i just put force on a second bike in the past 2 weeks. performs just as nice as the de rosa i set up last year. imagine that.

there are still plenty of continental and domestic teams who are using force. maybe you should read:

http://www.cyclingnews.com/tech.php?id=tech/2008/features/tdl_local_rides

the reality of racing outside of the protour, where teams actually pay for some/all of their gear as opposed to being gifted by sponsors. naturally if sram sponsor a protour team they give them red not force ... duh!! i'll be happily taking one or both of my force bikes to the australian nationals in 2 months.

sideshow_bob said:

woo hoo ... thread has successfully been turned into frothing and foaming alfeng sram rant fest.

i just put force on a second bike in the past 2 weeks. performs just as nice as the de rosa i set up last year. imagine that.

there are still plenty of continental and domestic teams who are using force. maybe you should read:

cyclingnews.comtech.phpOpen ↗

the reality of racing outside of the protour, where teams actually pay for some/all of their gear as opposed to being gifted by sponsors. naturally if sram sponsor a protour team they give them red not force ... duh!! i'll be happily taking one or both of my force bikes to the australian nationals in 2 months.

I'm sorry you continue to think that a REALITY CHECK about components is a "rant" ... but, I guess that's your prerogative if it makes you feel better.

FWIW. Yes, it is "how you ride" that makes a difference rather than what a person rides ... that should be a given. AND, it is why I am mystified why some people sometimes embrace components just because they may get a "team discount" if they aren't fully sponsored to use said components.

Regardless, and I am serious, I hope you do well at the Nationals.

alfeng said:

I'm sorry you continue to think that a REALITY CHECK about components is a "rant" ... but, I guess that's your prerogative if it makes you feel better.

FWIW. Yes, it is "how you ride" that makes a difference rather than what a person rides ... that should be a given. AND, it is why I am mystified why some people sometimes embrace components just because they may get a "team discount" if they aren't fully sponsored to use said components.

Regardless, and I am serious, I hope you do well at the Nationals.

I have a email into FSA about the problem, I have not measured the gap yet ut it has to be at least 1/8", I tried the green cup and it is just about the size spacer I would need to take up the gap.
But I am concerned that the crank arm does not go all the way on the spindle splines, I have checked the splines and the arm and the arm splines seem to taper down the further on it goes, best I can tell about .003 to .004 thousand not much but enough !! Are they supposed to be tapered?
I will see what FSA says. The arm only goes about half way on the splines of the spindle.

Thanks for the input guys.

I am running an FSA SLK carbon compact crankset with mega exo BB so I've confronted some of the same questions you have. First, the primary function of the "green disk" (in addition to confusing people) is actually for use in pressing the bearings into the cups. It is not a spacer, in spite of what well-meaning respondants have stated in this thread. Second, your issue of left crank arm not fitting fully onto the splines of the spindle may have a couple of causes. Make sure that you've included the rubber shell spacer (part #6 in the installation manual) between the BB shell and the left side cup, and the O-ring (#10) between the cup and the left crank arm. The spindle has a slight taper, so the crank arm won't immediately slip on all the way until the crank arm meets the bearing cover. Remember to put Loctite 641 on the end of the spindle and the splines of the crank arm (important!). Put the crank arm on as far as it will go, and insert the M18 fixing bolt (add blue Loctite 242 to the bolt threads if it isn't already there) and carefully tighten the bolt. As you tighten, the crank arm will be pressed futher onto the spindle splines. Torque the fixing bolt to 44-54 Nm. If you've been living right, the crank arm, O-ring, and bearing cover will all meet with no gap, and the crank will spin smoothly. However, I know that FSA has experienced some quality issues in mating the spindle and crank arm (I had problems undersized crank spindles, and FSA quickly replaced the cranks), so it's possible that your spindle diameter could be too large (size matters!). If still in doubt, call FSA. They're hard to get on the phone, but very helpful once you can speak with someone.

After my initial problems with the SLK (had to replace it under warranty twice within the first month of use), I've put 6,000+ miles on it with no problems. Good luck to you!

mwestray said:

I am running an FSA SLK carbon compact crankset with mega exo BB so I've confronted some of the same questions you have. First, the primary function of the "green disk" (in addition to confusing people) is actually for use in pressing the bearings into the cups. It is not a spacer, in spite of what well-meaning respondants have stated in this thread. Second, your issue of left crank arm not fitting fully onto the splines of the spindle may have a couple of causes. Make sure that you've included the rubber shell spacer (part #6 in the installation manual) between the BB shell and the left side cup, and the O-ring (#10) between the cup and the left crank arm. The spindle has a slight taper, so the crank arm won't immediately slip on all the way until the crank arm meets the bearing cover. Remember to put Loctite 641 on the end of the spindle and the splines of the crank arm (important!). Put the crank arm on as far as it will go, and insert the M18 fixing bolt (add blue Loctite 242 to the bolt threads if it isn't already there) and carefully tighten the bolt. As you tighten, the crank arm will be pressed futher onto the spindle splines. Torque the fixing bolt to 44-54 Nm. If you've been living right, the crank arm, O-ring, and bearing cover will all meet with no gap, and the crank will spin smoothly. However, I know that FSA has experienced some quality issues in mating the spindle and crank arm (I had problems undersized crank spindles, and FSA quickly replaced the cranks), so it's possible that your spindle diameter could be too large (size matters!). If still in doubt, call FSA. They're hard to get on the phone, but very helpful once you can speak with someone.

After my initial problems with the SLK (had to replace it under warranty twice within the first month of use), I've put 6,000+ miles on it with no problems. Good luck to you!

Thanks for the reply, I have a email into FSA right now and will try to call them later today, I am east coast and they are west coast and I did not get done working on the bike till after they were closed Friday night.
I have a 8000 BB and did not receive a rubber spacer (#6) in the box.
I will check again when I get home but do not remember seeing it!

I think I got either an over sized spindle or under sized crank arm as it will only go on about half way and that is trying to crank it on with the M18 Fixing bolt.

I would assume the crank arm should fit all the way onto the spindle splines?

Fujiman said:

I have a email into FSA about the problem, I have not measured the gap yet ut it has to be at least 1/8", I tried the green cup and it is just about the size spacer I would need to take up the gap.
But I am concerned that the crank arm does not go all the way on the spindle splines, I have checked the splines and the arm and the arm splines seem to taper down the further on it goes, best I can tell about .003 to .004 thousand not much but enough !! Are they supposed to be tapered?
I will see what FSA says. The arm only goes about half way on the splines of the spindle.

Thanks for the input guys.

Newer FSA splines are tapered after some of their left hand crank arms fell off. Get a big wrench and tighten it till it stops. Lots of torque. green loctite isn't a bad idea either. But if you did use the green spacer, the crank is all the way of and it still knocks back and forth, your shell is probably less than 68mm. Just get a thin BB cup spacer and space it till the arm is all the way onto the arm, not play and no binding. The only system that accounts for mis-sized BB shells is the Campag system. All other require the BB shell be 68mm. Too big-face it. Too small, spacers.

Peter@vecchios said:

Newer FSA splines are tapered after some of their left hand crank arms fell off. Get a big wrench and tighten it till it stops. Lots of torque. green loctite isn't a bad idea either. But if you did use the green spacer, the crank is all the way of and it still knocks back and forth, your shell is probably less than 68mm. Just get a thin BB cup spacer and space it till the arm is all the way onto the arm, not play and no binding. The only system that accounts for mis-sized BB shells is the Campag system. All other require the BB shell be 68mm. Too big-face it. Too small, spacers.

I have checked the shell and it is within .001 thousand of 68mm, checked with dial caliper 5 places on the shell.

IF I crank it all the way with a big wrench how will I get it off if I need to?

Fujiman said:

I have checked the shell and it is within .001 thousand of 68mm, checked with dial caliper 5 places on the shell.

IF I crank it all the way with a big wrench how will I get it off if I need to?

umm with the same amount of torque used to install it, it's got a self extracing end cap on it.

a) as posted above are you using a torque wrench? if you are torquing to say 55 and not getting it up the spindle, then thats an issue in and of itself. if you aren't using a torque wrench and simply by feel you're thinking it's not going on ... i'd check with a torque wrench.

b) as another poster wrote there are differernces in QC. one of my sets of cranks is pretty easy to slip the arm up the spindle, the other is a much tighter fit. ymmv.

c) if the gap is 1-2mm the spacer will sort that out. if it's as you've said an 1/8" then that is not going to fix the issue.

i suspect it's a tight fit (as it should be) and that you are under torquing it.

--brett