The Bad Granny. A picture is worth a thousands words, right? This frame is living proof that a little extra rubber, laid back geometry, and quality steel is really all you need in life… most of the time.

The Bad Granny has been around since day one here at Sour. We wanted a fun side-project, and an hommage bike seemed like a perfect fit. Singlespeed it, run gears, race it, ride it, commute it, it’s up to you! This frame can handle it all, as long as “all” ends with a cool beverage and good company.

The Bad Granny may be the same as the OG mountain bikes, but it is anything but ancient. Boost spacing, internal dropper routing, and all the other modern day standards are present and accounted for on this frame… no worries about running fancy robo-shifting if that’s your thing!

All of this, built by hand in Saxony!

All Sour frame are now made in Germany, by us, right here in Saxony. Production pre-orders happen quarterly, but frames can be ordered at any moment of the year. With the exception of special orders, sizes, and frames, all orders are expected to have a 6-10 week delivery time.



1049,00 €*



1299,00 €*




Handmade Sour Bicycles CrMo frame

Tubing: heat treaded, multiple butted tubing

Dropouts: 12mm x 142mm thru axle

Seat clamp: 35.0 external

Headtube: 44 mm

Bottom bracket: 68 mm BSA with eccentric shell

Axle: 12 mm x 142 mm thru axle

Seatpost: 31.6 mm

Brake standard: IS2000 disc

Recommended fork travel: 80 mm – 100 mm

Wheel size: 650b x 2.4“ / 29“ x 2.3

More facts:

Dropper post routing Two water bottle options


Axle: 15mm x 100mm thru axle

Brake standard: IS2000 disc brake

Steerer tube: tapered 1.5“ -> 1 1/8“

Rake: 50 mm

Fork length: ca. 470 mm       

Max. tire dimension 29“ x 2.4“

Light cable routing option

2 eyelets per fork leg

Frameweights incl. powdercoating and small parts

Bad Granny Size M = 2950g +/- 75g

Bad Granny Size L =3080g +/- 75g

Fork Bad Granny: 1275 +/- 50g

All weights in grams g.
All weights with powder coating and averaged with 3 frames per size.

Delivery items

Frame: Frame, Excentric bottom bracket, Derailleur hanger (derailleur/Singlespeed), Axle and Seat clamp

Frameset: Frameparts + Fork, front axle and Acros Headset