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Discussion Starter · #1 ·
Hi. New here. First thread.

I'm trying to upgrade the crankset on my 2015 Roubaix SL4 Comp Disc. It currently has a Praxis/Turn Zayante m30 50/34 compact crankset. I'm upgrading to Ultegra FC-6800 50/34.

(1) Do I have to replace the bottom bracket when I replace the crankset?

(2) Also, what special tools do I need to do this? Besides an 8mm hex to get the Praxis crank off the bike.

Thanks.
 

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Hi. New here. First thread.

I'm trying to upgrade the crankset on my 2015 Roubaix SL4 Comp Disc. It currently has a Praxis/Turn Zayante m30 50/34 compact crankset. I'm upgrading to Ultegra FC-6800 50/34.

(1) Do I have to replace the bottom bracket when I replace the crankset?

(2) Also, what special tools do I need to do this? Besides an 8mm hex to get the Praxis crank off the bike.

Thanks.
What I suggest:
A good probability you have a threaded BSA bottom bracket on that bike. A quick picture would expose the bottom bracket…if bearings are external and your bearing cups are fluted like a Shimano BSA BB.
I suggest you replace your BB. An Ultegra BSA BB is cheap and will last 20K miles if you don’t ride much in the rain. Ultegra crank + BSA BB is an outstanding combination.
So depends what type of BB you have to remove the crank. Crank removal is easy with basic tools. If you have any questions…post pics here…or…contact Praxis for guidance.
Good luck
 

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Discussion Starter · #3 ·
What I suggest:
A good probability you have a threaded BSA bottom bracket on that bike. A quick picture would expose the bottom bracket…if bearings are external and your bearing cups are fluted like a Shimano BSA BB.
I suggest you replace your BB. An Ultegra BSA BB is cheap and will last 20K miles if you don’t ride much in the rain. Ultegra crank + BSA BB is an outstanding combination.
So depends what type of BB you have to remove the crank. Crank removal is easy with basic tools. If you have any questions…post pics here…or…contact Praxis for guidance.
Good luck
Thanks. Here's a pic of my bike with the old Praxis/Turn crank still on it. Grey Carbon Metal Composite material Steel
 

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Great news for you is your pic confirms you have an English threaded BSA BB...same as used with Shimano BB's. Now...a good probability is..the Praxis spinde diameter is 24mm just like your soon to be installed Utegra crankset so you could 'try' and install your Ultegra crank using the BB you have. But I wouldn't. When pulling it apart, spend $30 more and install a fresh Ultegra BB. But if you try using your old BB...confirm current Praxis crank spline diameter with an inexpensive vernier caliper you can pick up where they sell tools, even if laterally spacing is a mm or two narrower or wider with old B, the beauty of an Ultegra crank..or 105 or DA is...it will easily accommodate this because of its adjustable straight flute spline...a truly fantastic crank design in my opinion...rock solid, easy to install.
HTH


Thanks. Here's a pic of my bike with the old Praxis/Turn crank still on it. View attachment 316642
 

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Discussion Starter · #5 ·
Thanks so much for a prompt and helpful response. I'll stop by the local bike shop and pick one up. I had bought the new ultegra crankset, chain, and cassette online so I really didn't want to bother them with questions when I didn't buy those parts from them. Thanks for your help.
 

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Discussion Starter · #6 ·
So I guess what I'm reading about these bottom brackets is that there are three different kinds of threading? English... Italian... and BB72? Is that right? And I guess there is a special wrench for bottom brackets that Park Tools makes. And is there special grease that I need to put in there as well? And also torque only to a certain point?
 

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Thanks so much for a prompt and helpful response. I'll stop by the local bike shop and pick one up. I had bought the new ultegra crankset, chain, and cassette online so I really didn't want to bother them with questions when I didn't buy those parts from them. Thanks for your help.
Just tell them you want an Ultegra Bottom Bracket for a English Threaded BB. You also need the wrench to remove the cups and reinstall new BB. Please note, they have oppose threads on each side of the bike.


  • Normal R.H. thread on Left side of bike
  • Opposite/Reverse L.H. thread on Right (drive) side of bike
 

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So I guess what I'm reading about these bottom brackets is that there are three different kinds of threading? English... Italian... and BB72? Is that right? And I guess there is a special wrench for bottom brackets that Park Tools makes. And is there special grease that I need to put in there as well? And also torque only to a certain point?
Only one you have to be concerned with is English Threaded...not Italian threaded or Press Fit BB72.

Here is the Park Tool you need for your BB:
https://www.amazon.com/Park-Tool-Bottom-Bracket-Hollowtech/dp/B009W68CCQ

Note: the little black serrated knob on the other end is to adjust the lateral preload on your Ultegra crank finger tight prior to torqueing the two pinch bolts for left crank arm to spec. Nose around the web for all torques....you can swag the 30 ft-lbs or so for the Park Wrench I reference. You can also buy a large special socket with 16 ribs that fits over the BB cups you can connect to a torque wrench...either solution. If you have any question...go to youtube and search Ultegra crank installation and a video or five will pop up.

No special grease is required. I use standard automotive grease...Mobil 1 sold at autoparts stores. Any grease will do. Apply to all surfaces....BB outer theads...and BB shell inner threads and on spindle of crank before pushing it through bearing cups.

HTH

PS: I will give you a tip that will really help you that is missed on the web and on youtube. To me, too many hacks work on bikes and don't understand stress and strain. Once you pull the crank off your bike, take is down off the repair stand and set the bike firmly on the ground straddling your top tube applying pressure downward on the top tube. That is the most secure way to both remove and install threaded BB cups. Best leverage and least amount of assault to the frame. Many do it on the bike stand which puts too much stress on the frame and hard to get the proper torque to the BB both off and back on. Let the tires push into the ground...not the frame stress on a stand is my advice.
 

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bad news, the rbx comp disc has an osbb (bb30). my wife rides this bike and the praxis works bb is for bb30. so you need either a praxis works adapter for shimano cranks and the matching tool to remove the installed m30 pw cups. or the better and durabel solution is to press in a sram/truvativ bb30/bsa adapter (with locite 609) and you can use every bsa bottom bracket! this is what i did with the bike of my wife and with many other bb30 bikes. no problem, never!
 

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bad news, the rbx comp disc has an osbb (bb30). my wife rides this bike and the praxis works bb is for bb30. so you need either a praxis works adapter for shimano cranks and the matching tool to remove the installed m30 pw cups. or the better and durabel solution is to press in a sram/truvativ bb30/bsa adapter (with locite 609) and you can use every bsa bottom bracket! this is what i did with the bike of my wife and with many other bb30 bikes. no problem, never!
Not his bike bro. Take a look at the picture. The bottom bracket shown is threaded. The telltale sign are the grooves around the 'external bearing cups'. BB30 bikes have no external bearing cups and no grooves. The grooves are for a 16 pin spanner wrench to unthread the cups. Spesh makes and has made a lot of BB30 bikes. Not his bike.
 

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Not his bike bro. Take a look at the picture. The bottom bracket shown is threaded. The telltale sign are the grooves around the 'external bearing cups'. BB30 bikes have no external bearing cups and no grooves. The grooves are for a 16 pin spanner wrench to unthread the cups. Spesh makes and has made a lot of BB30 bikes. Not his bike.
This is not true, the Roubaix has a BB30 and not a threaded, the Ultegra BB will not work. The splines in the picture are from the Praxis BB30/PF30 bottom bracket, seen here. https://www.praxiscycles.com/product/m30-conv-bb30-pf30/ If he really wants to "upgrade" to Ultegra he will have to run either adapter cups with a BB30 bottom bracket, which in my opinion is a down grade as they always creak and make noise. Or the other option is to run a conversion Bottom Bracket such as Praxis https://www.praxiscycles.com/conversion-bb/ so he is still not using the Ultegra BB. I have Ultegra cranks on a BB30 frame and am using adapter cups and it is annoying how much noise they make. I will be upgrading to Praxis BB this winter.

SS-
 

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My bad guys. Color me astounded that from the factory Specialized is taking a BB30 frameset and using a Praxis conversion sleeve to mount what turns out to be a BSA Praxis crank. Basically they are selling out to their supplier. In theory that sleeve plus longer spindle crank should be more costly...BB30 bearings are cheaper, and heavier and less stiff. But apparently the deal they cut with Praxis which gives Praxis good marketing for both crank and sleeve wins the day over any allegiance to BB30...their BB of choice on their flagship Sworks bike. OP, I stand corrected. I had no idea Specialized would "sell out" like this. Specialized through the years has mixed and matched BB's on their different level Roubaix's. For example in 2015...same year as your Comp OP, Specialized spec'ed BSA for their Roubaix Expert SL4 which is a model above the Comp.
Pretty clear its all about dollars for them and has nothing to do with any performance difference between BB's....to spec BB30 on a lower level bike like the Comp and then 'convert' it to a different BB type with a sleeve. They could have easily made the Comp model in BSA like they do the non disk Expert.
So, my apology. Last two posters are correct. This is the first time I have ever seen a 'conversion' sleeve on a bike that came 'converted' at the factory just so Praxis could put what they market on their bike.

PS: So OP...what to do. Leave the Praxis conversion sleeve in place for your new Ultegra crank. They cost about $80 USD to replace.
Be sure to measure the spindle diameter of the Praxis crank once removed. If it measures 24.0mm, your Ultegra crank will be plug and play. Ride it until the bearings fail.
 

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This is not true, the Roubaix has a BB30 and not a threaded, the Ultegra BB will not work. The splines in the picture are from the Praxis BB30/PF30 bottom bracket, seen here. https://www.praxiscycles.com/product/m30-conv-bb30-pf30/ If he really wants to "upgrade" to Ultegra he will have to run either adapter cups with a BB30 bottom bracket, which in my opinion is a down grade as they always creak and make noise. Or the other option is to run a conversion Bottom Bracket such as Praxis https://www.praxiscycles.com/conversion-bb/ so he is still not using the Ultegra BB. I have Ultegra cranks on a BB30 frame and am using adapter cups and it is annoying how much noise they make. I will be upgrading to Praxis BB this winter.

SS-
SS.
The book is out on the Praxis sleeve and a comment if I may because it seems that you want to move toward the Praxis sleeve for your Ultegra crank because your BB30 creaks. Word up. Some Praxis sleeves creak too. Reason is, one side of the Praxis sleeve is a very light metal on metal press just like BB30.

To save you $50 bucks, when your creaky BB30 wear out....my advice....don't waste your money on $80 Praxis sleeve. Install fresh cheap ABEC-5 BB30 bearings in your frameset properly with Locitite. There is nothing wrong with Wheel Mfg adapters to mount your Ultegra crank. Its your bearings that are creaking in the BB shell which can be church quiet with Loctite. With proper Ultegra crank preload adjustment, the Wheel Mfg spacers can't rattle.

There are kluges SS and there are kluges. Pick one. But for my money, I would save $50 and Loctite BB30 bearings and ride in silence with excellent Ultegra crank. Having now studied the Praxis sleeve design which includes anecdotal reports out inf the field, the Praxis sleeve is only slightly better than BB30 in terms of creaking and worse if you are a big power rider. But...if you Loctite BB30 bearings, there is no issue with BB30. This step sadly is missed by many including many bike shops for expediency.

Praxis could have done a better job designing their sleeve. Three things limit the design:
1. metal on metal interface without Loctite on one side that can creak
2. a tolerance sensitive lateral lock out when torqueing halves together that can apply an insufficient lateral force to keep the sleeve in place...especially problematic with a strong rider and low tolerance BB shell width.
3. an O ring on one side of the sleeve to take up tolerance and tolerance stack up affects lateral compression.

They could have designed their sleeve to be less sensitive to bike BB shell width tolerance.
 

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It's not the bearings that creak it is the adapter sleeves that take the diameter from 30mm to 24mm for Shimano cranks that creak. The Praxis Conversion BB isn't a different press in BB with adapters, it essentially turns a BB30 into a threaded BB for Shimano cranks. It does this using a collet system where the outside bearing cups have sleeves that screw together inside the bottom bracket shell. One of these sleeves expands as the other is screwed in causing it to "lock-in" to the BB shell preventing any movement. I think you are looking at their standard BB30 (they call it M30) and not their conversion BB which is different, https://www.praxiscycles.com/conversion-bb/ . Granted not all frames can use this Conversion Bottom Bracket and have to use the adapters. Luckily this is for my Felt which has a standard BB30 shell. You have to remember Shimano uses a 24mm diameter shaft on their cranks not 30mm so standard BB30 bottom brackets don't work with them.

And as far as the Praxis Conversion bottom bracket goes (not their standard one), the only complaints I have heard/read about is installation and removal can sometimes be a pain. And believe me I have done a ton of research on it. From everything I have gathered it is the best solution out for going from a BB30 to a 24/22mm crankset.

SS-
 

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It's not the bearings that creak it is the adapter sleeves that take the diameter from 30mm to 24mm for Shimano cranks that creak. The Praxis Conversion BB isn't a different press in BB with adapters, it essentially turns a BB30 into a threaded BB for Shimano cranks. It does this using a collet system where the outside bearing cups have sleeves that screw together inside the bottom bracket shell. One of these sleeves expands as the other is screwed in causing it to "lock-in" to the BB shell preventing any movement. I think you are looking at their standard BB30 (they call it M30) and not their conversion BB which is different, https://www.praxiscycles.com/conversion-bb/ . Granted not all frames can use this Conversion Bottom Bracket and have to use the adapters. Luckily this is for my Felt which has a standard BB30 shell. You have to remember Shimano uses a 24mm diameter shaft on their cranks not 30mm so standard BB30 bottom brackets don't work with them.

And as far as the Praxis Conversion bottom bracket goes (not their standard one), the only complaints I have heard/read about is installation and removal can sometimes be a pain. And believe me I have done a ton of research on it. From everything I have gathered it is the best solution out for going from a BB30 to a 24/22mm crankset.

SS-
Forgive me for saying you are wrong, but you are wrong. You wrote, "It's not the bearings that creak it is the adapter sleeves that take the diameter from 30mm to 24mm for Shimano cranks that creak."

Either can creak and for different reasons and neither have to creak 'ever'. There are probably 50,000 BB30's out there with Wheel Mfg Adapters with Shimano crank and only a very small fraction of them creak and that is due to assembly error which is common. BB30 + Wheel Mfg Adapter + Shimano crank is one of the most popular combinations today among race bikes including Specialized bikes. They never have to creak. So if yours creaks it isn't the parts...unless your bearings are bad, you don't know how to set it up and many more than not know how to do it properly and I know because I have fixed countless screw ups with this combination coming out of bike shops from club riders.
 

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My bad guys. Color me astounded that from the factory Specialized is taking a BB30 frameset and using a Praxis conversion sleeve to mount what turns out to be a BSA Praxis crank. Basically they are selling out to their supplier. In theory that sleeve plus longer spindle crank should be more costly...BB30 bearings are cheaper, and heavier and less stiff. But apparently the deal they cut with Praxis which gives Praxis good marketing for both crank and sleeve wins the day over any allegiance to BB30...their BB of choice on their flagship Sworks bike. OP, I stand corrected. I had no idea Specialized would "sell out" like this. Specialized through the years has mixed and matched BB's on their different level Roubaix's. For example in 2015...same year as your Comp OP, Specialized spec'ed BSA for their Roubaix Expert SL4 which is a model above the Comp.
Pretty clear its all about dollars for them and has nothing to do with any performance difference between BB's....to spec BB30 on a lower level bike like the Comp and then 'convert' it to a different BB type with a sleeve. They could have easily made the Comp model in BSA like they do the non disk Expert.
So, my apology. Last two posters are correct. This is the first time I have ever seen a 'conversion' sleeve on a bike that came 'converted' at the factory just so Praxis could put what they market on their bike.

PS: So OP...what to do. Leave the Praxis conversion sleeve in place for your new Ultegra crank. They cost about $80 USD to replace.
Be sure to measure the spindle diameter of the Praxis crank once removed. If it measures 24.0mm, your Ultegra crank will be plug and play. Ride it until the bearings fail.
It's funny how you're still in here talking like you have the slightest idea what you're talking about.
 

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Hi. New here. First thread.

I'm trying to upgrade the crankset on my 2015 Roubaix SL4 Comp Disc. It currently has a Praxis/Turn Zayante m30 50/34 compact crankset. I'm upgrading to Ultegra FC-6800 50/34.

(1) Do I have to replace the bottom bracket when I replace the crankset?

(2) Also, what special tools do I need to do this? Besides an 8mm hex to get the Praxis crank off the bike.

Thanks.
Short answers:

1. Yes, you have to replace the bottom bracket when you replace the crankset. The bottom bracket you have is designed only for the Praxis crankset in a BB30 frame.

2. You will need the special Praxis works bottom bracket tool - the M30. Theirs is not compatible with Shimano's. If you're just going to ditch the crankset, I wouldn't buy the tool, I'd just take it to your LBS (call to confirm they have the tool) and they should be able to pop it off for less than the $25 tool. Unless you're planning on putting this crankset back on something, in which case it's probably worth having around.

There's a lot of muck in this thread. If you want me to clear any of it up feel free to ask. If you don't, those are good answers to your questions.
 

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Short answers:

1. Yes, you have to replace the bottom bracket when you replace the crankset. The bottom bracket you have is designed only for the Praxis crankset in a BB30 frame.

2. You will need the special Praxis works bottom bracket tool - the M30. Theirs is not compatible with Shimano's. If you're just going to ditch the crankset, I wouldn't buy the tool, I'd just take it to your LBS (call to confirm they have the tool) and they should be able to pop it off for less than the $25 tool. Unless you're planning on putting this crankset back on something, in which case it's probably worth having around.

There's a lot of muck in this thread. If you want me to clear any of it up feel free to ask. If you don't, those are good answers to your questions.
OP,
I did some digging on Praxis website because Mason sounded pretty convinced that the BB you have will not fit a new Ultegra crankset and he is quite right.
More insidious proprietary $h!t Praxis does to make their crank only work with their BB so they can sell more BB's. They put a step down from 30mm to 28mm for their M30 crank which is used on BB30 bikes with the sleeve you show OP in the picture you posted. So no, that Praxis sleeve only works with the Praxis crankset and not with a 24mm Ultegra crankset.

Praxis crank + Praxis BB specs:
30MM DRIVE – 28MM NonDrive – The M30 bottom bracket family is for the M30 cranks. The M30 spindles are 30mm and then have a step-down to 28mm to lock on the Non Drive bearing. These use a drive side wave-washer for the bearing preload, and a 30MM Drive bearing with a step down to 28MM Non Drive bearing. The Zayante, Alba, Girder and Cadet all use the Praxis M30 bottom bracket.


And yes, the Praxis BB cannot be removed with the std Shimano BBT-9 spanner wrench because the bearing cups are larger in O.D.

OP, here is the tool....two tools actually to remove the Praxis sleeve. One side has to be held and torqued against the other side to remove the collet sleeve or the sleeve will rotate within the BB30.

Praxis M30 Bottom Bracket Tool - Fair Wheel Bikes


In summary OP, you have a couple of different options to mount a new Ultegra crank on your BB30 bike.
1. Obtain the proper Praxis sleeve with 42mm OD for BB30 and 24mm inside diameter bearing bore for Shimano crank spindle.

or:

2. Install BB30 bearings + Wheel Mfg Adapters....this is by far the more common installation and if done properly won't creak and in fact it has a lower probability of creaking compared to a Praxis BB if you follow Praxis's instructions.

Those are your options if you must have an Ultegra crank on your BB30 bike.

Me, OP...what would I do? I would install a BB30 crank and not an Ultegra crank on your bike. No adapters, no sleeve...or ride the Praxis crank and BB combo which is decent, just a bit heavy.
 
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