Shaft Drive Klunker bike

Rat Rod Bikes Bicycle Forum

Help Support Rat Rod Bikes Bicycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Joined
Sep 18, 2019
Messages
1,674
Reaction score
6,069
Location
Twente, the Netherlands
Rating - 0%
0   0   0
Hey Ratters,

I'm working towards my first completely scratch built bike.
And I thought; Lets share the whole process!

At the moment I am working on setting up and arranging my workshop, since I'm slowly working towards building frames for customers.

Regarding this bike I had in mind: I have five brand new shaft drives in boxes. Three 'singlespeeds' or 'three speeds' and two with an threaded rear sprocket.
1000033599.jpg

Two types: Right is for regular hubs like the Shimano CB-E110 or Nexus 3.

At the moment I am doing lots of inquiry! Measuring, calculating and looking for good mountainbiking geometries.

The shaft drives 'chainstay length' is fixed, so that is why I can't build a long chainstay (belly mounted BB) cruiser with this.

Right now I am figuring out the measurements of this shaft and how I build a durable frame with this.

Unfortunately VERY fat tires won't fit, probably a maximum of 2 inches, depending on wheelsize.... which is dependant on the internal gear ratio....

1000033554.jpg

1000033555.jpg

1000033600.jpg

1000033603.jpg

Measuring the dropout width.

1000033604.png

BB shell.

20240915_155753.jpg

My sketch of the bike.
A looptail, shaft driven klunker bike :inlove:

I intend to use CroMo tubing.
 
Little update:

I checked the intended dropout width in multiple ways: In my alignment jig and by assembling/adjusting the rear hub.

1000033609.jpg

1000033610.jpg

1000033611.jpg

Shimano CB-E110 hub.

1000033615.jpg







I also checked the Ratio: 1:2
1x crank turn = 2x wheel turning.

Tire clearance is meh. We'll see what we can do with that.
 
Bottom bracket shell is machined. Only a section to be removed that has to be milled:
1000033660.jpg

1000033782.jpg



This is how the bottombracket shell looks in the BRIK bikes (a Dutch brand that sells bikes with shafts).
1000033783.jpg

1000033784.jpg



Youtube video link

Since the 'open section' of the bottom bracket, especially in the corners, has a higher level of stress and tension, I decided to thicken the ends and have that part a lot stiffer.
I purposely designed the open section with a radius, so that tensions do not concentrate too much in a 90 degree sharp angle.

The bottom bracket is a 51,2 inner diameter (almost the same as a US BB) and 57mm outer diameter on the thinner section. The ends are 60mm. So a central wall thickness of 2,9mm :thumbsup:

I don't think this will be a light bike, but then you have more energy downhill :p
 
Last edited:
Neat. I've wanted a shaft drive bike for twenty plus years.

Are you designing with Creo?
 
Neat. I've wanted a shaft drive bike for twenty plus years.

Are you designing with Creo?
Well, I might be open to selling a frame/bike when its done ;)
I am indeed designing with Creo Parametric! How did you recognize it? Solid Works is common too :thumbsup:
 
I could tell by the font. I use Creo at my job (senior drafter at Colt).
Very cool! At my employer, we work with Creo Parametric and the Windchill system for drawing data storage.
In general, it works really good. I can even work from home and log in to a virtual desktop (the machine at my work does the heavy lifting then).

Shells are done, but I think I need to check the inside angles again and remove a bit more:
1000033816.jpg

1000033826.jpg

1000033827.jpg

No problem ironing that out. You can see the gaps and the shell that can go more to the right.


1000033820.jpg

CroMo tubing is here too!

Working on a geometry sketch.

Seat tube will be 28mm.
Chain- and seatstays 15mm.
Downtube 35mm.
Top tube(s) 28mm.

I'm preparing the bender for a 15mm loopytail.

The next days I will have a lot to do:
Saturday I'm enjoying a day at the Dutch mountainbike museum (800 bikes!).

Monday I will attend brazing class.
Looking forward to this!
 
Windchill... my boss calls it "Windshield". We laugh every time.
 
Dutch mountainbike museum

I just can't wrap my mind around the fact, that the Netherlands as the very definition of a flat country has a MOUNTAINbike museum... 🤯
 
I just can't wrap my mind around the fact, that the Netherlands as the very definition of a flat country has a MOUNTAINbike museum... 🤯
What should it be called then?
FLATainbikemuseum :thumbsup:
The Dutch always are excited about something they don't have :p

I will post pictures of some of the 800/900 bikes they have in a thread here on RRB soon. It will be picture heavy then!

In relation to this topic:
Look what I found in the museum:

B1 bicycle. 26". They use these in a dusty mine since a chain gets dirty fast.
20241005_115001.jpg

20241005_114955.jpg

20241005_115052.jpg

20241005_115124.jpg

Seeing that last picture. It seems that its (the BB) welded first and then machined for the shaft protruding from the frame when assembled.
Also little tire clearance.
 
At the mountainbike museum I met a guy who is also enthousiastic about Klunker bikes. We met via a Dutch marketplace and he saw one of my project on RRB's I believe. We decided to meet at the museum and ride :cool:
He also met Paul from Atomic cycles last year. Incredibly cool.
We had fun and he seems a great guy. We'll probably ride again!

This was his ride:
20241006_134500.jpg

1952 Schwinn Hornet with Araya's and a Shimano CB-E110 coasterbrake. Beautiful to see it on the mountainbiking trails :inlove:
 
Super interesting! I wonder, how difficult would it be to widen the bottom bracket? Like, a longer BB axle and an outboard left side bearing? That might allow for wider tires....
 
Super interesting! I wonder, how difficult would it be to widen the bottom bracket? Like, a longer BB axle and an outboard left side bearing? That might allow for wider tires....
I thought that too!
Well, the gearing has a certain angle to allow the shaft to move 'outwards' to the dropout width.
I don't know, what will happen when I change that angle (I need new housing for the bearings and, such).
Also the BB width will change. Which, all in all, might pose quite a challenge.

But I do have more shafts (sets) lying in my shack, so I can experiment with another bike.
Maybe even fabricate a bike with open bearings (sealed industrial) and open shaft. :crazy2: I've got plenty of ideas!

My bottom bracket shells (2x) are done and fit perfectly! (pictures below)
Now I can concentrate on the geometry of the Klunker bike and start with tube bending/notching and such.
First I need to re-arrange my shed, since bike building and bending stuff requires space :thumbsup:

If anyone has a great geometry suggestion, I'm open to it and exploring.

1000035142.jpg

1000035143.jpg
 
Last edited:
Is this XL geometry interesting perhaps?
I will compare it to my current klunker, which I like but has a little bit short top tube.
The chainstay is obviously fixed on this shaft drive (445mm).

1000035162.jpg
 
I sketched a CAD geometry for reference (I will do it a bit differently when I feel like it) and I started with the first tube miters and alignment.

1000036931.jpg

57mm BB saw.

1000036933.jpg

I marked the spot on the assembled BB and started aligning in the JIG.

1000036934.jpg

Very tight tube mitre! Love it!

1000036939.jpg

Not fully clamped yet, I need to clean and check a few things first.
The BB and seat tube alignment JIG parts can't be aligned since the BB is not centered here. The shaft drive piece is off centre.

Example:
20241005_115052.jpg

Example.
 
Oh yea, forgot the geometry:
(Crude sketch)

I am not entirely sure if I keep the chainstay looptail like this. Now it looks like and elevated chainstay.
The left chainstay can be different and attached to the bottom bracket.....

GEOMETRY PROPOSAL1.jpg

20241117_142846.jpg

Comparison I hand sketched before.
 
http://www.commuterbicycles.com/incline.htm

I found Incline shaft drive bikes are still listed for sale, whether they have them or it's a outdated website?
My guess is they made a batch of them in the early 2000s and are still trying to sell the old stock to recoup their investment.
Yet another case of reinventing the wheel. Shaft drive bikes were invented over 130 years ago. Those were all 1 speed, single tube tires and no brakes. Like they ever went fast enough to need brakes or there were things to not hit. ie, no cars, trucks or busses or even that many people out and about. I recall the drive shaft assembly on the Inclines was sold as a kit to oem manufacturers with few takers. I think there was a euro based company selling bikes where their are year-round commuters in lousy weather.

I bought a Incline Newport (the all red bike) about 18 years ago. I recall I got it on sale so it was much cheaper. Shaft drive 3 speed with 26" wheels. I thought it would be a good winter commuter in the upper midwest. All stainless steel, polished aluminum, plastic or powder coated aluminum frame. There were a couple parts that rusted up, one that I remember were the screws that held the plastic bell housing on, pretty minor. Anyhow the gear ratios weren't good and there is no way to change that. The old saying about 3 speeds was correct. Too High, Too Low and not quite right. With no option to change sprocket/cogs you are stuck with the factory ratios. I only rode it a few times and I though it was really slow and heavy feeling. The 7 speed ig hub version might have been a better choice but those were 700c only. Not good for our lousy local streets. My wife commuted on it for a winter or two and then refused to ride it anymore so i sold it. She's back to old school 21 speed mountain bikes for her year round townie. I have to change the chain & freewheel & brake pads & cables every year or two.

After reading the blogs at Arron's IGH hub service, it's clear that the newer Shimano Nexus 7 speed hubs with the seals still need periodic servicing. Combining with a shaft drive, the bike still isn't a never-needs-any-maintanence bike which is probably a primary selling point to some buyers.
 

Latest posts

Back
Top