1.5" oversized stem options

[greyhound_dog_1]

Hi
I would like to get a longer stem for my bike, but have found it difficult as it is a Cannondale and uses a random size 1.5" steering post not 1 1/8".

I would be looking for something 150+mm long and 10 degree approx rise to fit 31.8 handlebar (absolute min 150 mm long). Yes this is quite long, as I have fitted some swept back bars so that requires at least 5cm longer than current 10cm stem to obtain the original hand position.
Ideally I would go longer and have an adjustable angle on it as well.
Anyway I can't for the life of me find anything in 1.5, only 1 1/8 size which has plenty of ones like this.

What should I do?

I am assuming worst case is I would need a steering tube on the fork then a new headset with a shim and I can see this getting a bit expensive.

Ideally there would be a neat device to allow me to attach a conventional stem to the 1.5 post. Does it exist?

Cheers
Andy

 

[Rob3rt]

Are you sure it is 1.5"? My Cannondale's both have standard 1 1/8" steerers.

 

[fossyant]

Most likely 1.5 Bottom, but the top will be 1 1/8th. Very few manufacturers, like Canyon, do 1 1/4 !

 

[Rob3rt]

Tapered steerer?

 

[ohnovino]

AFAIK it's only Cannondale who make 1.5" stems, and they only go up to 120mm.

 

[greyhound_dog_1]

No it definitely is a 1.5" steerer tube as it says 1.5 on the top of the cover, and the 1 1/8 stem didn't fit.
It seems nobody else makes a large range of this size.

So I would need a tapered steerer tube, and a new headset, in order to use a standard stem? That sounds pricey.
No conversion device then? I was hoping for something like a 1.5 clamp with a 1 1/8 tube welded to the front of it...

 

[amaferanga]

Why not just sell the bike and buy one that fits you instead?

 

[ohnovino]

You could try a variant of the Sheldon Brown approach: use the smaller stem to clamp the steerer then fit a large quill stem on top

 

[greyhound_dog_1]

I have seen stem risers which have a clamp and then an extra bit of tube on the top of them. If someone made one of these but that had ID 1.5" clamp on the bottom and OD 1 1/8" on the extended tube at the top, that would be perfect. But I can't find that, either.
I've also looked into this thing called the Aber Hallo Stem, which clamps onto the end of the existing stem to add 5 cm, and adjustable angle, but it is for 25.4 not 31.8 bar.

 

[fossyant]

You could try a variant of the Sheldon Brown approach: use the smaller stem to clamp the steerer then fit a large quill stem on top

My eyes !

 

[greyhound_dog_1]

An update in case it helps others - yes, Cannondale only do 80,100,120mm in 5 and 20 degree 1.5-31.8 stems.
What I actually ended up doing was as follows:
Acor double bracket stem extender - this is 25.4 to 25.4 clamps.
Shim 31.8-25.4 on existing stem clamp, to allow Acor extender to connect.
Then got a new 25.4 handlebar. Total cost was like £35, which was similar to that of a 120mm Cannondale stem.
I now have an extra 50mm of reach with angular adjustment, and it is great.