Author Topic: Replacement seat rails too wide for stock Rad seat post and clamp - advice?  (Read 2308 times)

EleniS

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Hi all,  I'm hoping you can help. I just bought the Rad Expand 5 and the Serfas Super Cruiser seat to replace the stock seat. However, the distance of the rails on the Serfas seat are significantly (4-5mm) wider than the stock seat and the bracket from the Rad Expand seat post doesn't fit. It seems like too great a distance to try to squeeze the rails together to fit the Rad seat post and clamp; it seems like it could pop out of the bracket if too much stress is put on it while riding.

I'm new to e-bikes and I can't figure out if there's some sort of adapter I need to buy. Or, should I give up on the Serfas seat and try to find a seat that has the same rail width as the stock seat? I've attached two pics: one showing how the stock seat bracket is too small for the Serfas, and the other is a pic of the bracket that came with the Serfas, which doesn't at all fit the Rad seat post. I've seen online that others have used the Serfas  seat for their Rad bikes, but never mentioned the rail issue. Advice greatly appreciated! Thanks.  Eleni
« Last Edit: April 03, 2022, 12:41:18 PM by EleniS »

santacruzpaul

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I had the same issue with my Radrover installing my Cloud 9 saddle, I just used a little muscle to squeeze the rails where they needed to be. Over 1900 miles and all is still good,



Hi all,  I'm hoping you can help. I just bought the Rad Expand 5 and the Serfas Super Cruiser seat to replace the stock seat. However, the distance of the rails on the Serfas seat are significantly (4-5mm) wider than the stock seat and the bracket from the Rad Expand seat post doesn't fit. It seems like too great a distance to try to squeeze the rails together to fit the Rad seat post and clamp; it seems like it could pop out of the bracket if too much stress is put on it while riding.

I'm new to e-bikes and I can't figure out if there's some sort of adapter I need to buy. Or, should I give up on the Serfas seat and try to find a seat that has the same rail width as the stock seat? I've attached two pics: one showing how the stock seat bracket is too small for the Serfas, and the other is a pic of the bracket that came with the Serfas, which doesn't at all fit the Rad seat post. I've seen online that others have used the Serfas  seat for their Rad bikes, but never mentioned the rail issue. Advice greatly appreciated! Thanks.  Eleni

Radio Runner

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The distance the seat rails are apart is "mostly" standard and im guessing the Rad post is a bit narrow and the Serfas is a tad wide. Kinda a drag but once you get the clamp on there it wont come out. Better yet squeeze the rails with vise grips or some other tool just enough that in the relaxed position the rails rest at the right distance then assemble it without a worry at all. It wont take much so don't over do it with tons of force.

The clamp that came with the Serfas seat is for a different kind of seat post. Keep it around for another project some day.

mtblair

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I had the same problem putting a Cloud 9 seat on the standard Mini ST2 seat post. I used a large channel pliers to squeeze the rails together about 2mm to make it fit. Eventually, I bought another seat post so I could use the Cloud 9 clamp so I would have the option to change the seat angle.
Owner of a Rad Power Mini Step-Through 2

EleniS

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Thanks, everyone.  I managed to use tongue and groove pliers (that's all I had on hand) to squeeze the rails together enough to get the seat bracket and post on it. I'm realizing that the Serfas rails are a bit thicker than the Rad stock seat rails, but hopefully the bracket will hold.

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