Bottom Bracket Standards and Bafang mid drive motors

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Will the BBSxx fit in my bike? This is a question that many of us need help in answering. The question you should be asking first is "what kind of bottom bracket does my bike have"? You need to know the answer to this in order to understand how the BBS02 or BBSHD will fit in your bike and what size motor to choose. Next you need to know that Bafang BBSxx motors have a bottom bracket shaft diameter of 33.5 mm and are designed to fit into the bicycle bottom bracket standard known as JIS or Japanese Industrial Standard, which is very similar to our standard here in the US commonly referred to as "square tapered spindle", ISO/English, BSA, British, or "threaded". Available in 4 widths, (68 mm)(73 mm Oversize)(83 mm Some Downhill & FR bikes)(100 mm "Fat bikes"). Shell inside diameter is 33.6-33.9 mm. BSA has threads on the inside of the shell measuring 1.37 in x 24 TPI. Below is an example picture of the BSA threaded Bottom Bracket easily identified with the threads on the inside of the shell. This is what the BBSxx motors were designed to fit into. So if your bike has a threaded shell like the photo below, you are in luck, now all you need to do is order a motor in the correct width.

BSA english threaded Bottom Bracket.png

Fortunately Bafang makes the BBS02 and BBSHD motors in a variety of widths to fit several JIS and BSA bottom bracket shells with the proper knowledge. The BBS02 comes in one size only (68mm) unless you have a custom machined unit with a longer square tapered spindle other than a 68mm. The 68mm BBS02 and BBSHD can easily fit 73mm bottom brackets. All that is needed is longer fixing plate bolts and a 5mm spacer (or stack some small washers) to compensate for the 5mm difference between the fixing plate and the motor. Usually only the 4 notch M33 lock ring will fit on the remaining spindle shaft threads and the second outer lock ring may not fit. What this all means is this... a 68 mm BBS02 can easily fit in both 68 mm and 73 mm shells. Bafang now makes the newer BBSHD model available in a variety of sizes (6 to be exact) : 68, 73, 92, 100, 110, and 120 mm. Many people are unaware of this fact, but yes you can get a 73mm if you wish, but the flip-side is the 73 mm only fits 73 mm shells, making the 68 mm more versatile to swap to another bike someday, just a little food for thought. Well, you really don't need to continue reading if what you have read so far describes your bike. Everybody else without a threaded BB shell, keep reading, sorry, there will be a quiz for you as well.

Unfortunately, bikes comes with a multitude (6+ other standards) of varying widths and diameters, none of which have threaded shells, but instead use press in sealed bearing cartridges, which means you may not be able to install the BBSXX motor into your bike, so please pay attention. You may have one of these bikes or plan on buying one and don't even know it, thinking all you need to know is the width of your bottom bracket and order a motor between 73-100 mm and you are all set, sorry, this couldn't be further from the truth. DON'T BUY ANYTHING until you know exactly what kind of bottom bracket shell the bike has. I have dozens and dozens of emails from people who accidentally spent thousands of dollars on a bike only to find out the motor won't fit. They just assumed it would fit because the shell width was between 73-100mm, but they did not look at the shell type, or shell diameter, and the project comes to a screeching halt. Maybe soon we will have adaptors for the motor to fit more standards, but for now proceed with caution and try to make an educated build done right the first time.

There are several standards you need to be aware of that have larger diameter bottom bracket shells. It boils down to this, all the other standards (besides JIS and BSA) have larger diameter bottom bracket shells. The newer shell standards do not have threads in them at all and rely on press fit bearings being pressed in, instead of threaded in. They are notorious for having a "creaky" sound for this reason. Many bike manufacturers began adopting new standards around the 2012 time frame, some a little before, some a little after. What this means for you is, be especially careful when selecting a bike 2012 and newer because the chances of having a non BSA/JIS bottom bracket shell increases. The vast majority of older bikes pre-2012 have the appropriate threaded JIS and BSA style bottom bracket shells that the BBSxx motors were designed for and are usually a safe bet. Below are the standards to be aware of.

BB30: This was introduced as a new international standard utilizing a new, larger-diameter crank spindle and bottom bracket shell. With BB30, 42mm bearings press into the frame against inner snap rings. This is an open standard, like ISIS, that was originally introduced by Cannondale and has been adopted by crank manufacturers FSA, SRAM, and Zipp. If your bike has a BB30 bottom bracket, no worries, just get a BB30 to BSA adapter and the Bafang BBS02 or BBSHD will fit beautifully. Make sure to buy either a 68mm or 73mm BBSxx because BB30 is only made in these two widths. BB30 = good : )

bb30 image from website.jpg

Press Fit 30: Also called PF30, this is a variant of the BB30 design. The PF30 design uses BB30 sized bearings pre-installed in bearing cups. The bearing and cup are pressed into the bottom bracket shell. Because PF30 uses the same size bearings as a BB30, the cup material increases the bottom bracket shell to 46mm diameter. The PF30 system uses the same diameter spindle as BB30 and can be used with BB30 cranks. This is all wonderful you say, but... how do i get the motor to fit? Get a PF30 to BSA adapter and you are all set. This standard comes in 68mm or 73mm widths so choose your BBSxx motor accordingly. PF30 = good : ) PF30 and BB30 are the only press fit standards I know of that will fit the BBSxx motors with commercially available adaptors.

PF30 BB shell dimensions.jpg

The below mentioned do not fit the BBSxx motors.

PF41/BB86/BB92: This standard was originally introduced by Shimano as an internal bottom bracket standard and has since been adopted by other manufacturers as Press Fit 41, or PF41. Some fat bikes use this standard, including the Salsa Beargrease and Surly Ice Cream Truck, which use a PF41 bottom bracket in different shell widths (121mm for Salsa and 132mm for Surly). The bearing cups are pressed into the bottom bracket shell, and standard external bottom bracket bearings set inside these cups. Well that is all fine and groovy, but I am not familiar with any adaptors for this standard. There may be so please let me know so I can make a correction. To sum it up avoid this standard need custom machined solution : /
*UPDATE 6-26-2016 Adaptor for PF41 89.5mm wide available please see next post for details*

PF41 BB86 BB92.jpg

BB90 (Road) BB95 (MTB) BB121 (fat bikes): Exclusively used by Trek as an integrated bottom bracket standard, BB90/95-specific bearings press directly into the frame. Cranks with a 24mm spindle and originally intended for external bottom brackets will work with this system. I am not aware of any adaptors for this standard.To sum it up avoid this standard need custom machined solution : /

BB90 BB95 shell dimensions.jpg

Ok, I am getting bored and tired writing about standards that we can't install the BBSxx motors into.... the next few standards do not have adaptors for BSA, so I won't waste our time with details that don't matter and will update the info on the below standards later if things change.

BBright Direct fit: Avoid this standard custom machine solution : /

BBright PressFit: Avoid this standard custom machine solution : /

386 EVO: Avoid this standard custom machine solution : /

So as it stands now, the majority of newer standards are incompatible with the BBSxx motors. Here are some simple questions you can ask when selecting a bike to make sure you don't end up with one of these incompatible standards. What type of crank spindle is in the bike? If the answer is square tapered spindle, you are good to go. What year is the bike? Pre-2012 has a higher chance of being threaded. If you want a full suspension bike it would be a good idea to look for a used one made prior to 2012. Norco brand bikes still have newer post-2012 full suspension models with threaded shells that fit the motor. Is the bottom bracket shell threaded, yes, or no? If yes, the chances are almost certain the BBSxx motors will fit. If its not threaded, proceed with caution and make certain you understand what standard it is. PF30 and BB30 do have adapters available. What width is the bottom bracket? Knowing this allows you to get the proper sized BBSxx motor, 68mm, 73mm, etc...

Its a little confusing out there. Some vendors are offering spacer kits that may make it seem to you that all you need are their bottom bracket spacer kit and you will magically be able to install the BBSxx drive unit into any BB shell 68-73 mm, 73-100 mm, or 100-120 mm. This is just simply NOT the case. It is more complicated than just measuring the width of your bottom bracket. A spacer kit isn't going to do jack if the motor doesn't fit the diameter of the shell. Every installation is different requiring a different combo of spacers, chances are good you will need a different spacer other than one provided in the kit and end up using standard 1 or 2.5 mm spacers anyway. Spacers are extremely simple to obtain and come in a variety of thicknesses, do not make a purchase just because some spacers were whisked into the deal. Vendors do this to make use of the 3 most common motor sizes, 68 mm to fit both 68 and 73 mm, a 100 mm to fit anything from 73 to 100 mm, and a 120 mm to fit anything from 100 to 120 mm.This allows them to stock the motors in 3 sizes and simplify their inventory. The motor actually comes from Bafang in six different widths, 68-73-92-100-110-120 mm. That's right, it comes in 6 different widths, not just 3.

Most of the time the motor just does not bolt right into your bike the way you hoped. No big deal! There are easily obtainable spacers that bike shops and manufacturers use regularly called bottom bracket spacers. They are available in different thicknesses at any local bike shop or online. We have them too if you need them. You may find that when you put the motor into your bike's frame, it hits the chain stays (the frame tubes that connect to the rear tire) and cannot fit flush against the bottom bracket shell. That is when these bottom bracket spacers come in handy. Just slide these spacers to fill up the gap and get the motor positioned for an optimal chain line.

The photo below is an example of bottom bracket spacers used on a Motobecane Lurch with a 120mm BBSHD motor with a red Lekkie HD bling ring. The shell is a BSA threaded style 100mm wide. The 100mm BBSHD motor hit the frame and could not be installed. A longer 120mm BBSHD motor is used with 5, count them, 1-2-3-4-5, 2.5mm thick bottom bracket spacers filling the 10mm gap. All properly installed with a straight chain line.

Motobecane Lurch with 100mm BSA bottom bracket needs 120mm BBSHD to clear chain stay.jpg

One vendor claims to have custom machined adaptors for PF92, BB95 and BB121, but they have no mention of how or what is used, no pictures, no information, no proof, like a secret almost, hopefully its real, don't hold your breath. The only way this is possible is with a custom machined press in adaptor. Several people have told me this vendor was unable to provide them with what they needed for either of these standards they claimed to support. Please email me if you have any more information that can be added for the benefit of us all. This is a work in progress and your help is greatly appreciated. I have personally only done installations on bikes with threaded JIS/BSA, press fit PF30 and BB30 shells, and can confirm 100% the BBSxx can be installed in those BB shell standards. Continue reading for details of how to install in the BBSxx into PF30 and BB30 shells.

So here is what you can expect if your bike has either the PF30 or BB30 shells. There are press in adaptors made by FSA (Full Speed Ahead) that will adapt the PF30 and BB30 shells to BSA and allow the BBSxx motors to fit properly. They are available in two widths of 68 mm or 73 mm and for either PF30 or BB30 standards. The picture below is of a BB30 to BSA adaptor with choice of 68 mm or 73 mm width.

BB30 to BSA adaptor 68mm 73mm.jpg

Here are the PF30 adaptors below available in 68 mm, or 73 mm width.

PF30 to BSA adaptor 68mm 73mm.jpg

You must get these type of adaptors and ignore all other types that may pop up on your google searches. The press in adaptors shown above are the only adaptors you should be getting your hands on and ignore all others because they will not work and waste your time and money. You need this type of adaptor because it mimics a bare english threaded shell that the motor easily mounts into. See through the inside of the shell adaptor below.

View attachment 9

With these PF30 and BB30 adaptors, the diameter is reduced to fit the BBSxx motors perfectly. All you need to do is press in the appropriate adaptor into the PF30/BB30 bottom bracket shell with a Park Tool Headset Press and you will be able to install the BBSxx motor.

PF30 73mm press fit adaptor to BSA.jpg

You can see from the photo that the adapter is marked L and R for left and right. Start to press in by hand, apply loctite 609 and get your Headset Press handy, or just take it down to your local bike shop and have them remove your cranks and press this bad boy in for you. Most shops would charge 15-30$ for this and save you the cost of tools you may only use once. Insert the Park Tool HHP-2 and begin to slowly press in the adaptor.

PF30 pressed in with Park Tool HHP-2.jpg

Make sure the alignment is straight and do not be in a rush.

PF30 to BSA adaptor.jpg

Press in all the way until the press is flush against the BB shell.

PF30 to BSA flush against shell.jpg

Now the PF30 press fit shell looks just like a JIS/BSA threaded BB shell.

Ready to accept 33.5mm BBSxx spindle shaft.jpg

The light at the end of this tunnel is BBSxx goodness. This is going to make one sweet E-bike!

BBSHD installed in Specialilzed Fuse with PF30 bottom bracket shell.jpg

In the above picture is a BBSHD 1000 Watt 68 mm motor installed into a 73 mm PF30 shell with a BSA press fit adaptor from FSA. One thing to note is that the 68 mm size is versatile. It can fit both 68 mm and 73 mm BB shells with the spacers provided from EMPowered Cycles free of charge.

Below you can see the perfect chain line achievable with a properly spaced motor and a Lekkie Bling Ring. The chain line is very straight while in 5th gear on the 10 speed rear cassette. Shifts are smooth and precise with a proper chain line. This bike will have no problems using all 10 speeds.

ideal chainline with HD bling ring 68mm BBSHD into 73mm wide shell.jpg

This bike is a Specialized Fuse with 3 inch wide tires on 27.5 rims. It turned out to be a very nice e-bike. One of my favorite builds so far. There are many cool bikes like this out there with a PF30 or BB30 bottom bracket shell that can accept the BBSxx mid drive motor.

Specialized Fuse PF30 to BSA conversion BBSHD.jpg



Well it never fails, right now somebody is probably sending an email asking which motor they need to get for their bike, the 68 mm, the 100 mm or the 120 mm ??? Remember there are more sizes to choose from than just 3. I will try my best to help, but please take a moment to find out what type of shell your bike has and be able to answer 3 simple questions for yourself. What style BB shell does your bike have? The width? The diameter? It is up to YOU to know these basic details. These 3 simple details can make or break your BBSxx build.

So this whole article can be summed up to this...

- Know the year your bike was made, pre or post 2012.

- Look for threaded JIS/BSA, PF30, or BB30 shells, greatest preference on threaded JIS/BSA. *UPDATE Shimano Press Fit 41 89.5mm adaptor available*

- Know the width, diameter, and standard of your bottom bracket shell.

- A spacer kit will not solve your problems! It takes a little ingenuity and patience to install the BBSxx motors into some bikes.
 
Bafang 100mm BBSHD shimano press fit 41mm diameter 89.5mm - 92mm width to BSA/JIS adaptor.

View attachment 14

The BBSHD motor is designed for JIS/BSA threaded bottom bracket shells. If you have a 2012 and newer bike chances are good you may have a Shimano Press Fit bottom bracket shell. Full suspension mountain bikes such as the Giant Trance and Giant Anthem models have an ideal frame for battery placement, but motor installation was not an option due to the bottom bracket and motor incompatibility. We are able to fit BBS02 and BBSHD motors in the 2011 and older Giant Trance and Giant Anthem bikes because they use a threaded BSA bottom bracket, but were unable to install mid drives into the newer models after the BB shell design change to press fit. To solve this decided to custom machine an adaptor making it possible to install a 100mm wide BBSHD 1000 watt motor into the PF41 89.5-92mm wide BB shell. *Not intended for use on Carbon frames where shell may be too thick for motor clearance, intended for aluminum frames only.*

Intended for BB Shells with the following:

Shimano Press Fit 41 shell ID Giant Trance X4.jpg

View attachment 12

A very common bearing we see in these shells is the SM-BB71-41. This press fit bearing cartridge is another thing you can look for to determine if your bike has the compatible shell this adaptor is designed to work with.

Typical Shimano Press Fit cartridge bearing.jpg

Seen below, is a 2012 Giant Trance X4 that will soon be receiving a BBSHD.

View attachment 10

Its a 2 piece adaptor machined from 6061 aluminum designed to fit without needing a press and easily slides over the motor spindle shaft into the Shell's bearing races. You have the option of using Loctite 638 recommended for the adaptors gap clearance, but its completely optional. Our test results have shown it is not needed due to the way everything fits together when the M33 lock rings are tightened securely. The adaptor has been carefully designed and machined to fit a 100mm motor into a 89.5mm width PF41 shell without requiring additional spacers and up to 92mm with spacers on the two bolts between the fixing plate and motor body. This makes for a secure mechanical mount because the clamping force of the M33 lock rings compress the adaptor pieces against the non drive side shell face and the drive side bearing race wall.

View attachment 9

Drive side.

drive side adaptor inside bearing race.jpg

Non drive side.

non drive side adaptor presses against shell face.jpg

Tighten up M33 lock rings. Done!

Shimano PF41 to BSA adaptor no spacers needed.jpg

Plenty of threads left for second lock ring and no spacers needed. Clean and mechanically sound install. The motors on our installations have not rocked or moved at all, but if for some reason this does occur on your installation. You can easily drill, tap, and install a set screw on the non drive side adaptor seen below, but because the adaptors press up against the shell face and bearing race walls, we don't think you will ever need to do this.

optional set screw PF41 to BSA adaptor.jpg

optional set screw PF41 89.5mm to BSA adaptor.jpg

Finished install with no Loctite, no set screw, and no problems. Motor is held firmly in place against the frame downtube. So if you have a bike with the shell like this Giant Trance X4 and you want to install a powerful mid drive electric assist motor, you are in luck. The wait is finally over.

Installed PF41 89.5 to BSA adaptor.jpg

2012 Giant trance x4 BBSHD Lekkie HD.jpg

2012 Giant Trance X4 PF41 89.5 to BSA conversion.jpg

 

Attachments

  • Bafang BBSHD Shimano Press Fit 41 89.5mm to BSA adaptor EMPowered Cycles.jpg
    Bafang BBSHD Shimano Press Fit 41 89.5mm to BSA adaptor EMPowered Cycles.jpg
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Great stuff Matt, thank you for posting this up in detail. I have put some information in the wiki previously, but not with this detail about different BB types. I'll be looking to update/put this into the wiki, if that's ok with you. Thank you again! 8)
 
Well done, excellent post.

I had done some reading recently about the BB30 standard. Apparently, with carbon fiber frames becoming more popular a few years ago, it was realized that if the threads in a JIS (square taper) or ISIS bottom bracket shell became damaged...these frames were so expensive that a way was strongly desired to have the female threads be removable/replaceable. This happened about the same time that experiments showed that a larger diameter spindle that was hollow, was much stronger and also lighter than a solid spindle.

The "30" in the BB30 name refers to the outside diameter of the hollow shafts that the BB30 spindle is made from (and conversely, the inside diameter of the replaceable sealed bearings that support the shaft). It could have had acceptable performance and weight if the hollow shafts had been a little larger or a little smaller, but...mass-produced (replaceable) sealed bearings that have a 30mm ID were readily available, and very affordable (VXB.com).

Of course, now...there are frames using the BB30 that are not carbon fiber, but reading that story made sense to me. I had previously assumed it was just another company trying to push their new proprietary standard, so you could only get replacement parts from them, but now I believe BB30 is a good thing.
 
Hey thanks Lurkin! Yes please spread this along and add any more info that increases our knowledge base.

Thanks Spinningmagnets! Appreciate the insights on BB30 and thanks for all you do at Endless! You have been a great example of how to help spread knowledge that helps the next guy along on their project, thanks for all your great posts and help you have given to so many!
So far we have converted 3 Specialized Fuse bikes with the PF30 73mm wide shells using the FSA adaptor with no issues. The fuse is a very nice mid drive ebike platform. Great bike with fat, nimble, confidence inspiring tires.

Welcome Alex07, hope the info comes in handy.
 
Would anyone be able to tell me if the bottom bracket on a 2013 trek marlin would fit a BBSHD conversion? My Google fu is weak and I can't pick up particulars on threading. Hers a link to the bike in question. It's the Gary Fisher edition. http://worcester.craigslist.org/bik/5668909359

Other potentially helpful links:
Bike pedia: http://www.bikepedia.com/QuickBike/BikeSpecs.aspx?year=2013&brand=Trek&model=Marlin
Random forum conversion:http://singletracks.us-east-1.elasticbeanstalk.com/blog/forums/topic/bottom-bracket/
 
ivi_3 said:
Are there any websites for looking up information on brackets for those of us shopping for bikes expressly for future conversions? I'm having a hell of a timegetting any information on a Trek Marlin Gary Fisher edition from 2013.
Bikepedia has it listed as unknown: http://www.bikepedia.com/QuickBike/BikeSpecs.aspx?year=2013&brand=Trek&model=Marlin.

It has a Shimano Altus crankset. It's a low end bicycle, so it's unlikely to have exotic standards. The Altus is a square taper crankset, so the frame probably has a regular BSA treaded bttom bracket housing.
 
I have a BB30 Bike / Crankset,
and it really , Is a good thing .
Light weight, and they are the smoothest bearings I have ever spun, on anything .
When you install BB 30 Bearings and Crankset, before putting on the Chain,
spin the crank, it keeps spinning and spinning , also without the usual vibration that you feel on the Square taper and similar bb's , the BB30 system is smoother than butter.
I am happy for the progress, and BTW there are Aluminium Bikes that do not have
such a overly large diamater BB area like the Carbon frames do, If you want a Befang Mid-Drive you would find many of the
Alloy / Aluminium Bikes are able to be to compatible convertible to Threaded BSA/ISO .



spinningmagnets said:
Well done, excellent post.

I had done some reading recently about the BB30 standard. Apparently, with carbon fiber frames becoming more popular a few years ago, it was realized that if the threads in a JIS (square taper) or ISIS bottom bracket shell became damaged...these frames were so expensive that a way was strongly desired to have the female threads be removable/replaceable. This happened about the same time that experiments showed that a larger diameter spindle that was hollow, was much stronger and also lighter than a solid spindle.

The "30" in the BB30 name refers to the outside diameter of the hollow shafts that the BB30 spindle is made from (and conversely, the inside diameter of the replaceable sealed bearings that support the shaft). It could have had acceptable performance and weight if the hollow shafts had been a little larger or a little smaller, but...mass-produced (replaceable) sealed bearings that have a 30mm ID were readily available.

Of course, now...there are frames using the BB30 that are not carbon fiber, but reading that story made sense to me. I had previously assumed it was just another company trying to push their new proprietary standard, so you could only get replacement parts from them, but now I believe BB30 is a good thing.
 
EMPowered,

Your forgot / or didn't know about Praxis works.

Local Bike Shop Mechanic says they work better , for converting a BB30 Shell to BSA/ISO Threaded

Here: http://www.praxiscycles.com/conversion-bb/
 
ScooterMan101 said:
EMPowered,

Your forgot / or didn't know about Praxis works.

Local Bike Shop Mechanic says they work better , for converting a BB30 Shell to BSA/ISO Threaded

Here: http://www.praxiscycles.com/conversion-bb/

WARNING THIS SYSTEM WILL NOT WORK WITH BBSXX MOTORS
Yes we know about Praxis Works, they are located here in our backyard in Santa Cruz California. I have contacted them in the past and spoke with a rep by the name of Ross to confirm the below comment as fact.
This is a proprietary bottom bracket system that only converts BB30 and PF30 bottom bracket shells with ID 41mm to 46mm to use other types of cranks and spindles. It will NOT work with BBSxx motors nor will it allow for installation of BSA threaded cartridges. They do not provide an adaptor that reduces the opening down to 33.6-33.9mm and creates an empty threaded bottom bracket shell opening, which is what you need for BBSxx installation, this system will NOT accomplish that. Please readers look elsewhere, this is not a solution for us. It looks like it may be BSA because of the threads inside the sleeve, but the opening is not BSA and is a bigger ID approx 39mm.
PLEASE DO NOT BE CONFUSED READERS, THIS WILL NOT WORK!

Thanks for mentioning this ScooterMan101, now we can scratch this off the list too.
If you have a PF30 or BB30 shell the solution is to use the FSA press fit adaptors mentioned above in the first post.
 
EMPowered,

Good that you looked into this, as usual the mechanics at bike shops just do not know / have experience with e-bikes,
In fact my E-Bike was the first DIY E-Bike they had seen , it is a hub build . So they were not really talking about the Praxis
one working with a BBS02. It was my other bike ( non E-Bike ) that I was looking to build up , that has a BB30 Frame.
But I wind up in the end just getting a BB30 Crankset, to make things not so complicated, so I did not research the Praxis , I just remembered the Name .

BTW, Where on the BBSxx motors can a person shave off weight ?
The cost , and the heavy weight are what is holding me back from getting one.
 
Very good information but I still have a question. What is the clearance between the Bafang BB Shaft and the motor. Or to put it another way what is the maximum diameter of the bottom bracket shell?BBS01-BBS02 distance.jpg
Edit:
Why I'm asking: planning to build bamboo frame and need to know the amount of room I have for fiber wrapping.
 
The clearance is roughly 12-13 mm (roughly 1/2"). Some carbon fiber frames may be too thick. Just about all aluminum or steel frames are thin enough.
 
tahustvedt said:
The clearance is roughly 12-13 mm (roughly 1/2"). Some carbon fiber frames may be too thick. Just about all aluminum or steel frames are thin enough.
Thank Thee :D
 
Gor.GEE.ous

And good picture taking, too.

Surprised you got that to work on a full-suspension. So many of them (like the Diamondback) have a floating BB that would make this motor impossible.
 
So far all the BMXs Iv'e seen (cheap stuff) have been either a regular 68mm threaded BB, or an Ashtabula (one-piece) type.

But like any other bike, the manufacturer could use any of the standards they feel like, or invent their own (though the last is not likely).
 
EMPowered said:
Bafang 100mm BBSHD shimano press fit 41mm diameter 89.5mm - 92mm width to BSA/JIS adaptor.

file.php
Does this PF41 adapter affect the chainline? It's hard to see on the picture, but it looks like on the drive side the adapter pushes out the motor by 1-2mm? This might depend on the exact dimensions of the frame/bb I guess?
Thinking about buying a Giant Anthem 2.
 
No this does not push out chain line.
The drive side ring fits inside the shell so the motor fits flush.
Where are you getting this 1-2mm idea from?
You would only need spacers on the drive side of the motor if it touches the chain stay, which is bike specific, not related to the adaptor at all.
 
spinningmagnets said:
Of course, now...there are frames using the BB30 that are not carbon fiber, but reading that story made sense to me. I had previously assumed it was just another company trying to push their new proprietary standard, so you could only get replacement parts from them, but now I believe BB30 is a good thing.

Spinningmagnets, could I trouble you for input on my post here?

https://endless-sphere.com/forums/viewtopic.php?f=2&t=102325&p=1504702#p1504702

Your experience in the intricate details of middrive systems would be deeply appreciated.
 
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