BBSHD Build with GX Eagle 1x12?

S

saukit

10 mW
Joined
Jan 9, 2019
Messages
28
Hi there,
I am new to the forum and ebikes in general. Looking to jump in and build my first bike. I am pretty set on a BBSHD with a 52V battery, however I'm not sure that my planned donor bike will work. Said donor bike is a 2018 Kona Honzo set up with GX Eagle.

Does anyone out there have experience with the compatibility of a 1x12 drivetrain and mid drive motor? I don't intend to use the full range of gears, so any recommendations on how to limit the range would also be appreciated. Thanks!

P.S. frame is boost spacing, not sure if that makes a difference.
 
If you mean 12 sprockets on the rear wheel, then that means it has a derailer, which has limit screws. You can adjust those screws to limit out high and/or low gears, if that's what you mean.

If you mean that you don't want to use some of the intermediate gears, well, some sprocket clusters can be disassembled and reassembled in a different order, so you can do that along with the above limit screws.

As far as "compatibility" goes, that depends more on the frame shape and BB style and size whether any particular drive will fit or not. You'd need to look at each drive you're considering, for it's physical requirements/spacing/etc., and compare those to your frame.

There are some threads about BBS xx compatibility that may help you figure some of that out for the BBS drives. This list includes some of them
https://endless-sphere.com/forums/search.php?keywords=bbs*+compat*&terms=all&author=&sc=1&sf=titleonly&sr=topics&sk=t&sd=d&st=0&ch=300&t=0&submit=Search
 
amberwolf said:
If you mean 12 sprockets on the rear wheel, then that means it has a derailer, which has limit screws. You can adjust those screws to limit out high and/or low gears, if that's what you mean.

If you mean that you don't want to use some of the intermediate gears, well, some sprocket clusters can be disassembled and reassembled in a different order, so you can do that along with the above limit screws.

As far as "compatibility" goes, that depends more on the frame shape and BB style and size whether any particular drive will fit or not. You'd need to look at each drive you're considering, for it's physical requirements/spacing/etc., and compare those to your frame.

There are some threads about BBS xx compatibility that may help you figure some of that out for the BBS drives. This list includes some of them
https://endless-sphere.com/forums/search.php?keywords=bbs*+compat*&terms=all&author=&sc=1&sf=titleonly&sr=topics&sk=t&sd=d&st=0&ch=300&t=0&submit=Search
Click to expand...

Thanks for the input, yes the cassette has 12 gears, with the lowest gear being a massive 50t sprocket that I won't be using. I mainly just want to make sure I don't break anything as the GX drivetrain is not cheap. I searched before I posted and the only mention I could find specifically regarding GX Eagle was just a vague comment along the lines of "don't do it, you'll break stuff".

I'll check the limit screws but not sure if they have enough range to take the low gear completely out of play. I guess I could install a different cassette/shifter/rear derailleur but I'd rather not if I don't have to.

I'm pretty sure the frame will work, it's a standard 68/73 mm threaded BB. I've checked all of the compatibility lists and no one that I can find has installed a mid drive in a steel Honzo frame, although I don't see why it won't work. My main concern is that if the GX Eagle drivetrain is a no go then I might as well just sell the Honzo and buy a different donor bike that has proven compatibility.
 
If it's the earliest steel Honzo (circa 2013), I tried a BBS02 on mine and the right side of the unit contacted the chainstay so the mounts couldn't be tightened. Perhaps the BBSHD is different.
 
The BBSHD can be shimmed to make it fit as long as you have a standard BB. I had to add shims on the sprocket side to get it clear my frame and I had to shim the sprocket to get it positioned correctly. I don't have your frame but most frames are quite similar.
 
Thanks for the additional replies, I was figuring that I could use the included spacers/shims to get the motor to fit, if that doesn’t work I guess I’m back to selling the Honzo for a different donor bike.

Any other opinions on using the 1x12 drivetrain?
 
I had to get an additional 2mm spacer to get my BBSHD to just clear the chain stay. No big deal - got from Amazon.(I used the two supplied spacers as well. Take your time and it will come out great. Depending on what chainring you get you may need a spacer between the motor unit and the chainring. That I got from Luna. Everything fits and lines up great now but I did have to take my time to get it right. Every bike is slightly different in geometry. For me the best setup was when the chainring almost touches the chain stay (I think that is what it's called). My rear has 11 gears.
 
Volt_Ampere said:
I had to get an additional 2mm spacer to get my BBSHD to just clear the chain stay. No big deal - got from Amazon.(I used the two supplied spacers as well. Take your time and it will come out great. Depending on what chainring you get you may need a spacer between the motor unit and the chainring. That I got from Luna. Everything fits and lines up great now but I did have to take my time to get it right. Every bike is slightly different in geometry. For me the best setup was when the chainring almost touches the chain stay (I think that is what it's called). My rear has 11 gears.
Click to expand...

Great advice, thank you! Are you able to shift through your entire range of gears? Can I ask which front chainring you are running?
 
I'm running a 42 tooth Eclipse chain ring from Luna. The very low gears (large on back) are a stretch but I don't ever really need the first three. I would say that I can easily use the other 8 gears with no problem with chain angle.
 
Volt_Ampere said:
I'm running a 42 tooth Eclipse chain ring from Luna. The very low gears (large on back) are a stretch but I don't ever really need the first three. I would say that I can easily use the other 8 gears with no problem with chain angle.
Click to expand...

Thank much for the feedback, this is very helpful!
 
if it is possible to install an 8-speed cassette then i'd go for that. The chain will last longer and is much cheaper, so you can have some in spare without spending too much money.

Also the 42T chainring from luna is absolutely needed to get a proper chain line and it works better with 8 speed chain then with 9, 10 or 12 speed since they are more narrow.

the X12 is an absolute no go with a BBSHD, will only make you headaches so it would be best to get rid of that stuff
 
crossbreak said:
if it is possible to install an 8-speed cassette then i'd go for that. The chain will last longer and is much cheaper, so you can have some in spare without spending too much money.

Also the 42T chainring from luna is absolutely needed to get a proper chain line and it works better with 8 speed chain then with 9, 10 or 12 speed since they are more narrow.

the X12 is an absolute no go with a BBSHD, will only make you headaches so it would be best to get rid of that stuff
Click to expand...

Thanks crossbreak, I was leaning towards installing a different cassette/shifter/rear derailleur as I don’t want to experiment with an expensive cassette. I was leaning 10 speed but I will look at 8 speed options, what you are recommending makes sense. Thank you!
 
Saukit ,

The company called , Box Components are now making e-bike components like cassette / chain / shifter / derailleur.

https://www.boxcomponents.com/Box-Two-E-9-Speed-Chain

https://www.boxcomponents.com/Box-Two-E-9-Speed

https://www.boxcomponents.com/Box-Two-E

etc. https://www.boxcomponents.com/about
 
ScooterMan101 said:
Saukit ,

The company called , Box Components are now making e-bike components like cassette / chain / shifter / derailleur.

https://www.boxcomponents.com/Box-Two-E-9-Speed-Chain

https://www.boxcomponents.com/Box-Two-E-9-Speed

https://www.boxcomponents.com/Box-Two-E

etc. https://www.boxcomponents.com/about
Click to expand...

Thanks for the recommendation, I took a look and while their stuff looks interesting, the reviews I read mention that a chain tensioner/guide is usually needed which might make it a no go for this application. I have also looked at the SRAM ebike specific set but it's pretty expensive for experimenting.

I might just get the motor mounted, see what I'm dealing with on chainline, and then go from there. It would be nice if I could get a 1x10 to work. I will probably also buy both the 42t Lekkie and the 30t Luna chainrings. I have a feeling it will be tough to get a good chainline with the 42t, the bike has a 32t now.
 
Nobody says you have to use all of the gears. My 11 gear is fine for me - I just don't use the three lowest ones. With my 42 tooth chainring I would only use those gears if I was going up a very steep hill. My donor bike is new and it had two chainrings in front and the chain line was only good for the lowest three gears if I was on the inner small granny ring. I have a couple hundred miles on my Ebike now and I am happy with the chain line and gearing I have.
 
I use shimano 9 speed converted to 3 speed (36-21-14) on my bbshd (42t). 3 speeds are enough for me (I ride mountain trails mostly with PAS with 500-1000w). Used to have 5 speed but 3 is just perfect - less shifting. I replace 2 chains and cassetes per 3000 km. I would not suggeest anything over then 10 speed as it is more fragile . I would even use 8 speed stuff but is hard to get 36T good cassette.
 
I would also recommend an 8 or 9 speed cassette swap. The BBSHD will chew up you expensive cassette, there's no way around it. I've ran my BBS02 on 5, 6, 7, 8 and 9 speed cassettes and I'd say 8 is the magic number.

You could probably get by with less but 8 seems to allow me to keep the motor spun up into it's happy range under all conditions (I live in a land of very large steep hills). Plus they seem to be the cheapest chains.
 
Thanks all, lots of good advice here. I think I've settled on an 8 or 9 speed drivetrain, it's pretty cheap to buy shifters and derailleurs for these. I realize I could just not use the lower gears on the 1x12 but I have another bike running Eagle so I'll keep the spares in case something happens.
 
2old said:
If it's the earliest steel Honzo (circa 2013), I tried a BBS02 on mine and the right side of the unit contacted the chainstay so the mounts couldn't be tightened. Perhaps the BBSHD is different.
Click to expand...

Hi, Did you try using any spacers? I just picked up a 2013 Kona Honzo with the hope of putting a BBSHD on it. It's got a 73mm bottom bracket. I haven't taken the it all apart yet but eyeballing it looks like it will probably need ~10-15mm of spacers on the drive side for the 2 3/4" from center needed for the motor housing to clear the chainstays. I'm thinking I'll need to get the 100mm width variant of the BBSHD to fit enough spacers and still be able to get the lock ring on, and I'm worried about what that will do to the chainline and q factor...
 
The BBS02 was for 68 mm bottom bracket (BB) (or 73 mm with no lock ring) so it wasn't possible for me to space out the motor without really impairing the chainline and exacerbating the symmetry problem. Probably you can overcome the motor hitting frame situation with a 100 mm BBSHD and have the crankarms symmetrical, but the "Q" factor will suffer if that's a consideration for you. I just moved the BBS02 to a 68 mm BB and purchased Lekkie asymmetrical arms. BTW, I used 11-17-28 cassette rings spaced to the outside of the cassette body with 8-speed spacing in order to use a (possibly) stronger 8-speed chain and retain a straight chainline. Three gears were adequate for off road with the motor and I seldom used higher than level "1" of "5" assist.
 
Hi there!
Just to let you know. I have a Bafang HD rigged up with a GX Eagle 10 50 cassette,
Using 1 thin spacer with a Lekkie HD Ring.
This set up on my bike is an absolute dream to shift, without any gear-shift or brake sensors used or fitted. I just stop pedalling on shift. So smooth!
Maybe I'm lucky. Have a Sonder Evol bike from UK. The clearance at the rear triangle/Lekki is minute.
I am careful and take care not shifting under more than 3 PAS levels, so as not to strain the whole kabang on take up!
 
Oscdav said:
Hi there!
Just to let you know. I have a Bafang HD rigged up with a GX Eagle 10 50 cassette,
Using 1 thin spacer with a Lekkie HD Ring.
This set up on my bike is an absolute dream to shift, without any gear-shift or brake sensors used or fitted. I just stop pedalling on shift. So smooth!
Maybe I'm lucky. Have a Sonder Evol bike from UK. The clearance at the rear triangle/Lekki is minute.
I am careful and take care not shifting under more than 3 PAS levels, so as not to strain the whole kabang on take up!
Click to expand...

How did this setup hold up for you? I'm just now thinking of pairing a BBSHD with a SRAM Eagle GX 1x12 10-52t. I would love to have this gear range but have some concerns about durability. Let's see if I can bring this thread back from the dead :)
 
You must log in or register to reply here.

Similar threads

Cyb0rg d3ck3r
New Fat Tire BBSHD Build From Scratch! Need HELP Selecting Components!
Replies
16
Views
514
Bullfrog
B
N
Need Input for Trek Farley 7 Fat Bike Build
Replies
11
Views
1,557
Nuckingfuts
N
K
BBSHD - has always seemed to have high resistance when un-powered - Suggestions?
Replies
20
Views
1,610
Chuy
C
R
    • Like
Really good article comparing Bafang vs. Tongsheng vs. CYC
Replies
12
Views
10,624
999zip999
999zip999
R
    • Like
A critique of mid-drive riding recommendations (and hub drive criticisms)
Replies
15
Views
5,166
Bullfrog
B
Back
Top