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Discussion Starter #1
After owning a 2005 sixpack for a few years, I decided to give the 2010 5 spot a chance.
This is an amazing bike, however I wanted to change the HT Angle, the bike feels sooo different from what I am used to, especially going down and turning. The steering was unstable for me. (this is with a 150mm fox float 36, 710mm bar and a 75 stem)

As the annual budget for biking stuff has been exhausted and the 2011 frame was out of the question, it was either selling it or changing it.
As I love eveything else about this bike, I chose the latter.

Re-welding the head tube at the desired angle could have been nice, but impractical for me.
So the other idea was to run the fork stirrer at an angle through the head tube.
Angled headset cups for 1.1/8" are not yet available, so I had to make some of my own.
Some brain storming and a few hours on the Unigraphics NX5 produced the following model.
In the picture you can see the hollow headtube, the stirrer with bearings and the two cups.
 

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What's a stirrer?
 

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Discussion Starter #3
continued...

It took a couple of weeks till the right time was found to put the design into production.
The calculation based on the model shows a change of 1.69 degree.(C or F ? ;) )
But numbers aside, today I got to put it to the test...

Here are a few pics of the cups and how they look on the bike.
The cups are marked so I could align both, the design includes O-rings for better sealing of the bearing areas.

Enjoy.
 

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Now with flavor!!
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Pritt tee

frick kin

cool
 

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I think it's spelled "Sturr"


All you guys with CAD skills and machining equipment at your disposal make me a very jealous human.
 

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Discussion Starter #7
First impressions...

Took it for a spin this afternoon, about an hour of technical flowing singletracks, climbing the first half of the ride and going down the second half...

The bike the usually excells on the climbs felt stable and the front was not wandering even on steep climbs. the BB might have dropped a bit as I found myself hitting more rocks than I use to on those familiar climbs. climbing technical stuff was easier.
The bike rolled over stuff with less resistance than before.

Cruising on flat ground the steering fet more stable, more predictable and required less attention than usual.

On the way down I noticed the biggest change. The steering was much more stable and the bike rolled over everything with much less resistance. I was able to carry more speed through technical descents and corners than before. The bike felt way better cornering, I was not waiting for the front wheel to loose traction any more, the rear lost it first.. it was the first time I felt that the bike was "carving" corners (just like in skiing).
I think I managed to knock about 30 seconds off the time it usually takes me to finish the last 1.5 mile singletrack going down to the car park.
Took it apart again when I got back home to inspect it again after the first use.
Seems like it will outlast any other component on the bike.

One happy rider here!
 

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If you're offering, I think I might. Not for a turner though......something else. It would take a different modeling process to map out.
 

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Yeah yeah......I don't expect free work........which is why I said I was jealous.

Allllll righty then


Specialized SX frame. 1 1/8 top, 1.5 bottom. Tapered sturr fork. Give me at least 1.5 degrees.


GO!!!! :D
 

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Me likee too.

Turn my 2010 into a 2011 at lower cost (I hope). If you are ready to set a price, let me know too please.
 

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Discussion Starter #19
OK guys and girls..

I appreciate your feedback and will try and help the ones that are interested.
I did it in my free time with no intention to make it commercial. Just out of love to my hobby and in order to save me from getting a new frame. (this is not what I do for living...)

Modeling for different head tube lengths is not a problem, modeling for differnt head tube types (zerostack. tapered) is basicaly starting from scratch. the main issue is getting a CNC shop to free and setup a production machine for 2 parts.
Every different design needs to be programmed into the machine seperately.
I see there is a demand for the angled cups and that makes it an opportunity to try and get the shop to do them all in one campain.
The cost of design and manufacturing of such a set is roughly 150$ as they are taylor made for each and every bike. The achievable angle changes with HT size and length.

If you are interested, please PM me with the following details:

Head tube type (1.1/8" , Zero Stack, Tapered) (tapered can not be changed this way)
Steering tube type (1.1/8" or tapered)
Head tube length (find it in the geometry section, make sure you got the right year..)
Headset make and model (your top bearing assembly needs to fit nicely)
If you would like any special color at additional cost (anodized - red, black, blue, no complaints on hue please)

I will reply to each and everyone with the relevant information (achievable angle etc.)

Thanks
 
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