Steerer spacer height

The engineers at Easton told me the EC90 carbon fork is not to exceed 80mm of spacer length. I
thought that was an unusually high number, but they assured me that it was safe to use up to that
point. Has anyone used this fork with a spacer height of more than 1" without any issues? I'm using
the 1" steerer.

Thanks, John

 

John S wrote:
>
> The engineers at Easton told me the EC90 carbon fork is not to exceed 80mm of spacer length. I
> thought that was an unusually high number, but they assured me that it was safe to use up to that
> point. Has anyone used this fork with a spacer height of more than 1" without any issues? I'm
> using the 1" steerer.
>
> Thanks, John

can anyone explain why spacer height is such an issue, and stemlenght or handlebar width can
be ignored?
--
Marten

 

> can anyone explain why spacer height is such an issue, and stemlenght or handlebar width can be
> ignored?
> --
> Marten

Good question!!! Basically, it can't. You might want to ask a fork manufacturer that same question
and post their answer here.

Personally, I use elementary geometry to determine if the total leverage exceeds what would be the
case for the manufacturer's stated max height with a 120mm stem and work back from there.

Jim

 

"M-Gineering import & framebouw" <[email protected]> wrote in message
news:[email protected]...
>
> can anyone explain why spacer height is such an issue, and stemlenght or handlebar width can be
> ignored?
> --
> Marten
>

I suspect the steerer is designed to work with a certain length. A stem may be designed to accept a
certain load and may be over-engineered to sustain all foreseeable, normal forces that a rider can
produce with the widest bars conceivable. However, with the carbon steerer, they may not have the
latitude in dimensions to over-build the part to accept all possible loads. The further the steerer
gets out of the upper bearing area, the more cantilevered it is, making it weaker and weaker. The
fork designer probably did his math, came up with a number that worked and slapped a label on there
relieving them of some liability issues (but not all, conceivably). If they went through the trouble
of putting a label on there it's probably worth thinking long and hard about overriding that advice.

Cheers,

Scott..

 

mcgyyver-<< The engineers at Easton told me the EC90 carbon fork is not to exceed 80mm of spacer
length. I thought that was an unusually high number, but they assured me that it was safe to use up
to that point. Has anyone used this fork with a spacer height of more than 1" without any

We use 1.5 inches(4cm) on 1 1/8inch steerers and 1 inch(2.5cm) for 1 inch steerers..

I wouldn't use 8cm(3 inches) on any carbon steerer fork, particularly on a 1 inch carbon steerer.

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
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