Experience with seatpost mounted racks

damyth said:

I'm looking for some feedback from people with experience with seatpost
mounted racks, specifically those that allow panniers to be mounted.
In particular, I'm wondering how well these work tight(er) geometry
road bikes (shorter chainstay, no eyelets) and rear panniers for
commute purposes. For commutes, I'm carrying about 17 lbs including
laptop, books, and change of clothing. I guess my main concern is
stability of the rack, and in theory heel clearance shouldn't be as big
an issue since these allow panniers to be mounted higher.

They'll work, but don't strike me as being as stable as attaching a
regular rack using P-clamps on the seatstays (unless yours are fragile
carbon-fiber ones). I tour with full-size rear pannier bags on a
criterium, short chainstay, frame and haven't encountered any problems.

damyth said:

I'm looking for some feedback from people with experience with seatpost
mounted racks, specifically those that allow panniers to be mounted.
In particular, I'm wondering how well these work tight(er) geometry
road bikes (shorter chainstay, no eyelets) and rear panniers for
commute purposes. For commutes, I'm carrying about 17 lbs including
laptop, books, and change of clothing. I guess my main concern is
stability of the rack, and in theory heel clearance shouldn't be as big
an issue since these allow panniers to be mounted higher.

I'd love to hear people's experience whether this setup is likely to
work well or not.

I wasn't a huge fan. I ride a 60cm, so perhaps I'm not the normal
case, but the weight felt REALLY high to me. When I've ridden with
standard rack-mounted panniers, it was a much smoother ride. I also
had to REALLY clamp down on the mount to keep it from slipping around
hard corners and bumps. Don't use a nice seatpost.

damyth said:

I'm looking for some feedback from people with experience with seatpost
mounted racks, specifically those that allow panniers to be mounted.
In particular, I'm wondering how well these work tight(er) geometry
road bikes (shorter chainstay, no eyelets) and rear panniers for
commute purposes. For commutes, I'm carrying about 17 lbs including
laptop, books, and change of clothing. I guess my main concern is
stability of the rack, and in theory heel clearance shouldn't be as big
an issue since these allow panniers to be mounted higher.

I'd love to hear people's experience whether this setup is likely to
work well or not.

I use one on my good bike (I have a lot of bikes), although I use a
trunk bag, not panniers on it. It doesn't grip the seatpost tight
enought to prevent it from moving side to side. I solved that problem
by inserting rubber stips (that come with handlebar mounted accessories
like bike computers and such) between the clamp and the seatpost. That
works great.

You're right that the rack will place your cargo up much higher that an
eyelet mounted rack.

I don't put much weight on mine (jacket, lights, etc). For the things
you carry I think I would go ahead and get P-clamps and mount a real
rack on the back. I wouldn't feel good about cantilevering a lot of
weight off my seatpost, especially if it isn't steel.

Hope this helps,
Tom

damyth said:

I'm looking for some feedback from people with experience with seatpost
mounted racks, specifically those that allow panniers to be mounted.
In particular, I'm wondering how well these work tight(er) geometry
road bikes (shorter chainstay, no eyelets) and rear panniers for
commute purposes.

I have one, though I haven't used it much. It works OK, but don't put too
much weight in there. In comparison, a regular rack will hold more and is
more secure. I have used both on bikes w/o eyelets. Use p-clamps (sold
in hardware stores for securing cable to walls) to attach the regular rack.

For occasional use, a seatpost rack will be OK. They do have real weight
limits (under 20 lbs, certainly), and may rotate on the seatpost if you
jostle the bike around too much. OTOH, at least with these you can keep
the panniers far enough back to not interfere with your feet; a
frame-mounted rack on a bike with very short seatstays may require
fiddling to keep from bashing your heels into the panniers.

Quoted message said:

I'd love to hear people's experience whether this setup is likely to
work well or not.

Well? It works OK.

--

David L. Johnson

__o | If all economists were laid end to end, they would not reach a
_`\(,_ | conclusion. -- George Bernard Shaw
(_)/ (_) |

damyth said:

I'm looking for some feedback from people with experience with seatpost
mounted racks, specifically those that allow panniers to be mounted.
In particular, I'm wondering how well these work tight(er) geometry
road bikes (shorter chainstay, no eyelets) and rear panniers for
commute purposes. For commutes, I'm carrying about 17 lbs including
laptop, books, and change of clothing. I guess my main concern is
stability of the rack, and in theory heel clearance shouldn't be as big
an issue since these allow panniers to be mounted higher.

I'd love to hear people's experience whether this setup is likely to
work well or not.

What's the bike and seatpost size? If it has lower eyelets but no
upper, there are some different options. Two that haven't been
mentioned yet are the u-bolt based adapter kits, which are much more
confidence-inspiring than p-clamps IMO, and Tubus Fly/Luna racks. Also,
for many frames it's feasible to add your own lower rack threaded holes.

Nate Knutson said:

damyth said:

I'm looking for some feedback from people with experience with seatpost
mounted racks, specifically those that allow panniers to be mounted.
In particular, I'm wondering how well these work tight(er) geometry
road bikes (shorter chainstay, no eyelets) and rear panniers for
commute purposes. For commutes, I'm carrying about 17 lbs including
laptop, books, and change of clothing. I guess my main concern is
stability of the rack, and in theory heel clearance shouldn't be as big
an issue since these allow panniers to be mounted higher.

I'd love to hear people's experience whether this setup is likely to
work well or not.

What's the bike and seatpost size? If it has lower eyelets but no
upper, there are some different options. Two that haven't been
mentioned yet are the u-bolt based adapter kits, which are much more
confidence-inspiring than p-clamps IMO,

What is uninspiring about P-clamps? They work very well. 4 pieces of
steel wrapped around the seatstays, bottom and top. If the store
bought ones do not seem thick enough, they are, then you can buy
whatever thickness of steel you want and bend it into your own custom
made P-clamps. You could make P-clamps from steel so thick and strong
your frame would be torn apart long before the P-clamps gave way. The
rack would be destroyed long before the P-clamps gave way. The bolts
holding the P-clamps to the rack would break long before the P-clamps
gave way. And you could use Grade 8 bolts just to get some extra
security if you like. P-clamps, even the store bought ones, work very
well. I used them to attach the rack to the brevet bike this year.
They held just fine on 200, 300, 400, 600, and 1200 km brevets this
year. I always get a hoot out of people who dream up problems to worry
about.

and Tubus Fly/Luna racks. Also,

Quoted message said:

for many frames it's feasible to add your own lower rack threaded holes.

damyth said:

I'm looking for some feedback from people with experience with seatpost
mounted racks, specifically those that allow panniers to be mounted.
In particular, I'm wondering how well these work tight(er) geometry
road bikes (shorter chainstay, no eyelets) and rear panniers for
commute purposes. For commutes, I'm carrying about 17 lbs including
laptop, books, and change of clothing. I guess my main concern is
stability of the rack, and in theory heel clearance shouldn't be as big
an issue since these allow panniers to be mounted higher.

Quoted message said:

I'd love to hear people's experience whether this setup is likely to
work well or not.

I tried a cheap QR one from Nashbar. On it, the pannier support part doesn't
extend low enough for my panniers to clip on to it. Works fine for a
trunk bag though.

-alan

--
Alan Hoyle - [email hidden] - http://www.alanhoyle.com/
"I don't want the world, I just want your half." -TMBG
Get Horizontal, Play Ultimate.