CScott18

Hello,

First of all I'd like to apologize for several things: I really don't know a whole lot about bikes, and I'm not confident this is the right forum section to be posting this question in (if I'm wrong, please re-direct me, thank you).

I have a mountain bike and I'm trying to install a Schwinn seat post rack to it. I thought "loosen struts, slide post in, tighten bolts" would be easy enough to figure out, but once I picked up a rubber shim and realized I had NO clue how it's supposed to be used or where to put it, I gave up all hope.

This is a picture (from Google images) of the rack I have: https://ecx.images-amazon.com/images/...L._SL1200_.jpg I know where the post slides into, I don't know where the rubber shim goes or how to secure it. I also couldn't find any images of the rubber shim, either, for that I apologize.

No how-to videos I could find were helpful. Any help would be appreciated. Thank you!

Andrew R Stewart 

The shim is to accommodate the seat post diameter to the rack clamp diameter IF NEEDED. If the post is too small (as discovered when the clamp bolts are fully tight and the rack clamp is still loose on the post) then you open the clamp and place the shim inside it, around the post. If the shim is the correct thickness (and it might not be) it will fill out the clamp and with the bolts retightened the rack will now be snug.

BTW these racks are rather minimal in load capacity and tend to get pushed out of line easily. Almost every one I see needs aligning and more tightening, whether it is as tightened as it's design allows for. Having a shim between the clamp and the post just adds a squishy and slip prone layer, but it's the best they offer without a specific rack for each post size. Andy.

Andrew R Stewart 

We do I have egg on my face The rack isn't a seat post fitting one. Although all my comments most certainly do apply to the post clamp type...

The type of rack actually discussed is very common. It uses 4 mounting points to the frame. Two down just above the axle, usually to eyelets already in the drop outs. And two just above the rear brake on the seat stay tops, again often to pre existing eyelets. But sometimes the eyelett are not present and a "P" shaped surround clamp is required to loop around the seat stays to provide an eyelet mount.

I'm not sure what shim the OP is referring to, or how the post is involved. Andy.

CScott18

Andy,

Thanks for your feedback. The rack packaging describes the rack as a "seat post mount" rack, but I do know the picture I have is definitely the rack in my hand. "'P' shaped surround clamp" also seems to describe what came with the rack, though if those aren't shims, then I have no idea what the instructions on the packaging refer to.

I think I'll have to take everything to a bike shop and see what they can do. Your feedback regarding the picture I've posted, while very helpful and thorough, don't at all line up with the instructions that came with the rack, so unfortunately I'm still stuck. Thank you very much for your input though!

Andrew R Stewart 

Wouldn't be the first time either the wrong instructions or really badly translated ones got into a package. Andy.

coupster

If your frame does not have upper rack attachment points, you need to replace your seat clamp with one of these or
something similar in design.

Problem Solvers

alcjphil

If your bike has rear suspension, you will not be able to use that rack. You will have to buy a seat post rack

Bill Kapaun

Maybe if you tell us what bike you have?