Here is straight no clamp one
http://www.ebay.com/itm/XLC-Aluminum...item564fbb9594
And here is one with a clamp 400mm long
http://www.ebay.com/itm/BBB-BSP20-Sk...item5d2e0dec83
Personally I am not sure I would want to cruise around on a too smallish frame with extra 25.0 post sticking out. 26.8 I have done, but onlt an extra cm or two, but 25.0 might be noodly
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk