Although I was able to shoe-horn a 100mm BBSHD into my Phat Phuk FB 5 2.0 build, owners of the Bikes Direct Lurch bikes are not going to be anywhere near as lucky and will need to order a 120mm kit instead of the 100mm kit even though their BB is only 100mm. This post will talk about all sorts of BBSHD and BBS02 installation issues and how to correct them without (mostly) modifying the frame of your donor bike. There are tons of different BB types so you want to make sure you BB is compatible with the BBSxx before you buy the bike. Matt from Empowered Cycles did a great article outlining most of the common BB types and their compatibility with the BBSxx drive units here. As far as I know, Matt also custom built the only BBSHD custom pressfit BB bearing adapter for the BBSHD which is located here.

My chainstay is in the way & I don’t have enough threads showing to attach the lockring & mounting plate

Don’t panic. Lots of my builds have the secondary reduction gear that presses up against the chainstay. If you have at least 12mm of threads showing on the non-drive side then you’re golden. If you have less than 12mm of threads showing on the non-drive side then I recommend that you send the drive unit back to where ever you got it from and try to get the next bigger size. The BBSHD comes in 3 standard sizes 68mm, 100mm and 120mm. Try as hard as you can to explain how the problem is really the BBSHD reseller’s issue and they should have KNOWN your bike was not gonna fit that drive unit, and therefore they should eat all the shipping both ways. If you bought it from China that is going to be expensive to swap ship and most unreputable Chinese resellers will probably just have a good laugh at your expense. (see section on angle grinder below)

My non-drive side pedal is hitting the chainstay on the non-drive side no matter what I do

This happens about 15% of the time. The easiest fix is to install an offset crankarm on the non-drive side. They run about $25 and you can get them from Lectric Cycles right here or Doug at Cali-ebike. Next.

My bottom bracket is a weird size (not 68,73,100 or 120)

No matter what your BB size is you can probably get it to work if you’re willing to put in a little bit of effort. In general, whatever your BB size is to get the next BIGGER drive unit. Example : If you have a 90mm BB get a 100mm BBSHD, if you have a 110mm BB get a 120mm BBSHD.

If the difference is less than 5mm and you know for a fact that the chainstay will not interfere with the secondary reduction gear then you can instead pick the smaller size drive unit. Example : If you have a 73mm BB you can get the 68mm size, if you have a 105mm BB you can get a 100mm size.

If the drive unit is bigger than the bottom bracket then you will need large 34.75mm ID spacers set against the bottom bracket of the bike. If the drive unit is smaller than the bottom bracket on your bike then you will need spacers on the two bolts that hold the triangle mounting bracket against the bike. Whoever you bought the BBSHD should be able to help you get these spacers if you need them unless you bought from Alibaba or anyone in China other than Paul at em3ev.com in which case you’re probably out of luck. You can buy the small washers for the M6 bolts at almost any building supply store, I suggest stainless.

The two bolts should go into the drive casing at LEAST 5 mm. If you don’t have 5mm of bite then go buy some replacement M6x20 or M6x25 stainless steel bolts from McMaster Carr or your local hardware store. The BBSHD ships with M6x15mm bolts which are pretty small and have a thick lock washer on them leaving only about 14mm of bite. If your replacement M6 bolts do not have lock washers on them then don’t forget to put a bunch of blue Loctite on the bolts before you tighten them down the final time or your drive unit will loosen up on jumps. I don’t care if you like your drive units like you like your women, just trust me on this one.

The Golden Rule – Your mounting plate must be totally flat against the BB Side

You can never break the golden rule, you can plan all you want and get the spacers that you think you will need, but the only thing that counts is when you actually put the drive unit on your bike and try to get the mounting plate to work. If the mounting plate is flush against the BBSHD main drive shaft but floats above where the 2 bolts attach then you will need to add washers until all three contact points are flush. If your plate is flush against the mounting brackets for the 2 bolts, but it floats above the driveshaft then you will need to add 34.75mm ID spacers against the BB till they line up with the other mounting 2 bolt mounting brackets and the whole plate and the bolts are all flush. Make sure the little bumps on the metal mounting plate are facing TOWARDS the bike or it will sag down like a cow udder on your first jump.

There’s always the angle grinder

Let’s say you have 135mm BB on a fat bike. Are you out of luck? Probably. There is always the angle grinder and you can take a whole lot of material off the BB before you start running into any real problems. If you grind off the non-drive side expect that you will need an offset pedal (see above). I recommend only grinding down the non-drive side and putting a steel hose clamp that y ou don’t care about on the BB before you start to grind as a marker for how much you want to grind off. When you see sparks and you’re grinding an aluminum bike then you know you’ve gone far enough. The hose clamp will make sure the BB is square and flush which can be a little hard to do if you’re just eyeballing it. There is also a BB facing tool which you don’t have, but your bike shop will. This can clean up your BB face, but is too slow to use to take any real meat off.

Do not ever try to modify the chainstay on your bike. This is a bad idea and can lead to nothing good. I know I’m a funny guy, but I’m really not being funny here. *serious face*

Installing a massively offset aftermarket chainring like the Luna Eclipse or the Lekkie ring and it hits the chainstay

If your chainring hits the chainstay then the easiest way to deal with it is to space it out with washers or use a chainring spacer. The washers will have to be ground down with a grinder on one side and then you will need to hold them in place with glue from a cheap craft hot glue gun while you mount the chainring. Put the bolts in and put it on a small square of cardboard on the table face up so you can use the cardboard to lift up the chainring without all the bolts falling out. Put the ground down washers on the chainring with the ground down sides toward the center and put a tiny dab of hot glue on the outside rim of the washers (not enough to get in the way of the chainring). Then carefully lift up the cardboard square and mount the chainring carefully seating all the bolts before you tighten them.

You can only space the Luna Eclipse out about 7mm before the bolt heads start to hit the crank. To deal with this problem you can either grind down the part of the aluminum crank that is hitting the bolts OR you can space the entire drive unit out toward the drive side of the bike a few MM by cutting a short piece of pipe to use as a spacer around the axle shaft of the BBSHD. There are also spacers that are available from Lunacycles for this express purpose. If you space the drive a few mm it will fix the problem of having to massively offset the BBSHD aftermarket chainring.

But I don’t want to deal with all this stuff, I just want it to work

Too bad, if you want the latest and greatest then sometimes you have to spend a little bit of time beating your head against the wall. Lectric Cycles is preselling their e-Rad branded BBSHD 1000W kit here with spacers that are pretty much guaranteed to work with 68,73,92,100,110 & 120mm bottom brackets. I’ve bought and beat on 2 Lectric BBS02 750w eRad branded kits and had not had any real issues with them and Chris is a joy to deal with and sounds like he really likes me actually picks up the phone when I call. I needed some spacers for the chainring adapter on the e-Rad last year and after a couple of weeks and hardly any harassment on my part, they just magically showed up in the mail. Amazing.

Doug from California e-bike also seems to have lots of spacers for the BBS02 which will work well on the BBSHD and he also works very closely with Paul in China from em3ev.com. Doug is also a joy to deal with and once I sent him an email complaining about something that had failed and he never even emailed me back, he just sent the parts I needed in the mail without charging me. I spent a week wondering if he hated me and was ignoring me because I am a terrible person, and then WHAM *parts arrive*. Blew my mind.

Eric from Lunacycle.com & Electricbike.com (Chinese prices from a US vendor) is also working on getting together spacing kits for the BBSHD so if you tell him what you need and send him pictures of your build he can also help you out if you buy your drive unit from him (which I do). Eric is working on 18 different fit kits that is guaranteed to fit pretty much EVERY BB size and chain-stay intrusion from 68mm up to 125mm or you get your money back (that doesn’t mean much because your fit kit will be free with every BBSHD purchase).

Roshan of Biktrix up in Canada, is the countries de-facto Bafang BBSxx expert and an all around awesome guy, Aye? (‘Aye’ is Canadian for ‘said to express assent’). Whatever you need he will wave his magic wand and it will appear out of thin air.

Any of these fine and reputable vendors will not leave you hanging. Do yourself a favor and don’t buy from the cheapest Chinese vendors then lean on other reputable e-bike vendors for custom-made parts.

That is just lame and they will probably just ignore you.

I would.

Some large spacers are made of steel which I really don’t like and I find that aluminum is lighter and works much better because it is soft. If you can it is best to only install one big ring that is the right size or a little too big and not a bunch of skinny ones stacked on top of each other. The friction between the ring and the mounting plate is the only thing that keeps the drive unit from sagging down like a cow udder, so the fewer rings you have the better off you are. The rings are 34.75mm ID and around 41mm-44mm OD. The measurements are not crucial as long as the ID is 34.75 or greater. Any competent machine shop can quickly and easily make you a spacer out of any steel pipe, although getting it from a reputable e-bike vendor will probably be cheaper and way more convenient.

Can I get the BBSHD to fit on almost any bike on the market? With a little ingenuity and some elbow grease, the answer is a definitive yes. If your BB is too wide for your drive unit by less than 5mm or there is only a minor chainstay intrusion, then you will only have to add a few washers available at almost any hardware store. If you want to just have a BBSHD on a factory pre-built fat bike, well you’re out of luck. There is no BBSHD factory built fat bikes available yet in the US. If you want to buy BBSHD prebuilt conversions from a reputable e-bike dealer then it’s going to cost you a lot extra for work that you can easily accomplish on your own in only a few hours.

Building something yourself will bring you a sense of satisfaction in this life that is hard to replicate in any other way and it will create a connection with your bike that will last a lifetime…

… or at least until it’s stolen.

Ride On.

Watch cowspiracy, it’s really good and it’s not really about pirate cows. No animals were harmed (other than me) during the writing of this article. If you call yourself an environmentalist and you eat meat then you’re in for a rude awakening.

It’s the most important movie to watch of the decade.