"seat bag" for bottom bracket?
#1
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"seat bag" for bottom bracket?
I've recently gotten into using a frame bag and it impressed me how little the handling was affected by weight in the main triangle. It got me thinking of putting my seat bag with all my repair stuff (tube, inflator, co2, repair kit, etc) right above the bottom bracket (I'm currently putting it in the frame bag, but I actually have room below the bag to put a small triangular bag) . Any recommendations out there for something like this? I'm adding a picture of the kind of fit I'm looking for
thanks
thanks

Last edited by Symox; 12-12-21 at 12:05 AM. Reason: more detail
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AFAIK Specialized is the only one that makes something like that. I believe the are screwed in place. I imagine that whole area may be too tight to run straps around tubes.
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Specialized fitted the SWAT Box (as OP pictured) for only a few years on the last-generation (2016 - 2019) Roubaix/Ruby frames. They were almost universally hated by everyone, LOL. You can find the SWAT box itself used or occasionally NOS, but they are affixed using bosses drilled into the frameset - So not easily adaptable to bicycles not equipped with the extra bosses near the Bottom Bracket.
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#8
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I have this bag and it was mounted above the bottom bracket for a while , but I eventually took it off and went back to a regular seat bag
https://outbiking.co.uk/dakine-hotlaps-gripper/
https://outbiking.co.uk/dakine-hotlaps-gripper/

Last edited by Andrey; 12-13-21 at 12:31 PM.
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If your frame has a third set of bottle cage braze-ons under the downtube like this one, that's an even better spot to store tools and spares. The load is lower and less likely to get in the way, still between the wheels so handling is unaffected.

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A little different and serves a very specific need, but it works really well and I can confirm it's effect on handling (and rider awareness) is zero.

That red bag carries sandals. I came up with this after riding Cycle Oregon on this fix gear in 2012 and suffering foot injuries and toe infection from pulling up so hard and for so long. The sandals meant my feet were unrestrained in open air during the rest stop. (A couple of years later I removed the straps from my cycling shoes and installed laces. Problem solved.) This photo is proof that if you cannot see something and forget about it, its weight doesn't slow you down. This photo was taken on a two mile hill at the steepest point; 14.5%. So steep and hard that when I touched my forearm with the bar of soap hours later, it hurt! (I forgot to flip the wheel until it was too steep to stop and start in heavy bike traffic so I was muscling a 42-17. Really glad that being under the DT turned the sandals into no-see-ums. No-see-ums don't weigh anything.)
The issue I had to address very carefully was interference with the the wheels and drive train. Bike's a fix gear. If that bag slips into the path of either, well the drivetrain isn't stopping. Stopping the wheels rarely ends well. So I had that bag made to be a very snug fit and there is a quality toestrap around it, through a "belt loop" on the bag and between the cage and DT.

That red bag carries sandals. I came up with this after riding Cycle Oregon on this fix gear in 2012 and suffering foot injuries and toe infection from pulling up so hard and for so long. The sandals meant my feet were unrestrained in open air during the rest stop. (A couple of years later I removed the straps from my cycling shoes and installed laces. Problem solved.) This photo is proof that if you cannot see something and forget about it, its weight doesn't slow you down. This photo was taken on a two mile hill at the steepest point; 14.5%. So steep and hard that when I touched my forearm with the bar of soap hours later, it hurt! (I forgot to flip the wheel until it was too steep to stop and start in heavy bike traffic so I was muscling a 42-17. Really glad that being under the DT turned the sandals into no-see-ums. No-see-ums don't weigh anything.)
The issue I had to address very carefully was interference with the the wheels and drive train. Bike's a fix gear. If that bag slips into the path of either, well the drivetrain isn't stopping. Stopping the wheels rarely ends well. So I had that bag made to be a very snug fit and there is a quality toestrap around it, through a "belt loop" on the bag and between the cage and DT.
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No magic on the brake hoods. I just kept pushing them down until I didn't have chronic hand issues. What you see serves as excellent weight lifting handles. Seatpost is about 70mm setback. Seattube is 75 degrees so a 25c tire can slide far forward to accommodate a 24 tooth cog yet not be too far back when I'm running the 12 tooth because that's when I want really good handling! Seatpost clamp is around the center of the seat rails because breaking ti seat rails gets old. (If I were to do this bike again, I'd ask about a bent seattube but what I've got is pretty close to heaven.)
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I've recently gotten into using a frame bag and it impressed me how little the handling was affected by weight in the main triangle. It got me thinking of putting my seat bag with all my repair stuff (tube, inflator, co2, repair kit, etc) right above the bottom bracket (I'm currently putting it in the frame bag, but I actually have room below the bag to put a small triangular bag) . Any recommendations out there for something like this? I'm adding a picture of the kind of fit I'm looking for
thanks

thanks

i don;t like carrying stuff in my jersey pockets (other than a mask) except for last resort - like taking leg/knee warmers off...
The SPec SWAT thing they have built into the frame is a great idea. And I was thinking the same idea as your pic, above - but not wantiing a hard case which needs to secure to the DT or ST. I was thinking soft....
Hangup is I have and use both bottles/cages on prolly 2-3 rides each week, so it has to fit into the BB -V, beneath both bottle cages. So, the space available is max 5 inches from bottom V to the DT bottle cage. There just don't seem to be any bags/packs/soft stuff made for this, that will fit. Most all small and micro size under-saddle bags are all 6+ inches long....
Width doesn;t seem to be an issue - I have about 3 inches easy width on my tarmac.
3 options I could find which would fit:
1. Dakine Hot Laps Gripper - https://themtblab.com/2017/11/dakine...ag-review.html
2. Lezyne Caddy Saddle Bag in small will fit - the one with strap, not coupling...
3. Use a small general purpose nylon/polyester bag/sack.
some months and I still haven't found the perfect thing - so still searching... the Dakine is doable, and might hold enough...
REI carries the Dakine Gripper bag - so I'll see if they have it in the store, next time I visit...
a great idea though...
Ride On
Yuri
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I've been thinking about this all summer. Hoping to come up with something, to get the 'repair' stuff out of the seat pack, and make room cell phone, snack, maybe arm warmers (coolers).
i don;t like carrying stuff in my jersey pockets (other than a mask) except for last resort - like taking leg/knee warmers off...
The SPec SWAT thing they have built into the frame is a great idea. And I was thinking the same idea as your pic, above - but not wantiing a hard case which needs to secure to the DT or ST. I was thinking soft....
Hangup is I have and use both bottles/cages on prolly 2-3 rides each week, so it has to fit into the BB -V, beneath both bottle cages. So, the space available is max 5 inches from bottom V to the DT bottle cage. There just don't seem to be any bags/packs/soft stuff made for this, that will fit. Most all small and micro size under-saddle bags are all 6+ inches long....
Width doesn;t seem to be an issue - I have about 3 inches easy width on my tarmac.
3 options I could find which would fit:
1. Dakine Hot Laps Gripper - https://themtblab.com/2017/11/dakine...ag-review.html
2. Lezyne Caddy Saddle Bag in small will fit - the one with strap, not coupling...
3. Use a small general purpose nylon/polyester bag/sack.
some months and I still haven't found the perfect thing - so still searching... the Dakine is doable, and might hold enough...
REI carries the Dakine Gripper bag - so I'll see if they have it in the store, next time I visit...
a great idea though...
Ride On
Yuri
i don;t like carrying stuff in my jersey pockets (other than a mask) except for last resort - like taking leg/knee warmers off...
The SPec SWAT thing they have built into the frame is a great idea. And I was thinking the same idea as your pic, above - but not wantiing a hard case which needs to secure to the DT or ST. I was thinking soft....
Hangup is I have and use both bottles/cages on prolly 2-3 rides each week, so it has to fit into the BB -V, beneath both bottle cages. So, the space available is max 5 inches from bottom V to the DT bottle cage. There just don't seem to be any bags/packs/soft stuff made for this, that will fit. Most all small and micro size under-saddle bags are all 6+ inches long....
Width doesn;t seem to be an issue - I have about 3 inches easy width on my tarmac.
3 options I could find which would fit:
1. Dakine Hot Laps Gripper - https://themtblab.com/2017/11/dakine...ag-review.html
2. Lezyne Caddy Saddle Bag in small will fit - the one with strap, not coupling...
3. Use a small general purpose nylon/polyester bag/sack.
some months and I still haven't found the perfect thing - so still searching... the Dakine is doable, and might hold enough...
REI carries the Dakine Gripper bag - so I'll see if they have it in the store, next time I visit...
a great idea though...
Ride On
Yuri
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The chainwhip - 20 oz, 22" long and shop quality to use. My big cogs come off after I've climbed hills like this; so at very reduced levels of mental facility and physical strength!
No magic on the brake hoods. I just kept pushing them down until I didn't have chronic hand issues. What you see serves as excellent weight lifting handles. Seatpost is about 70mm setback. Seattube is 75 degrees so a 25c tire can slide far forward to accommodate a 24 tooth cog yet not be too far back when I'm running the 12 tooth because that's when I want really good handling! Seatpost clamp is around the center of the seat rails because breaking ti seat rails gets old. (If I were to do this bike again, I'd ask about a bent seattube but what I've got is pretty close to heaven.)
No magic on the brake hoods. I just kept pushing them down until I didn't have chronic hand issues. What you see serves as excellent weight lifting handles. Seatpost is about 70mm setback. Seattube is 75 degrees so a 25c tire can slide far forward to accommodate a 24 tooth cog yet not be too far back when I'm running the 12 tooth because that's when I want really good handling! Seatpost clamp is around the center of the seat rails because breaking ti seat rails gets old. (If I were to do this bike again, I'd ask about a bent seattube but what I've got is pretty close to heaven.)
This guy is an A N I M A L
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#16
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I also run and love frame bags. My first was an off-the-shelf Revelate bag semi-custom fit to my Surly ECR. It also did not go all the way to the bottom of the triangle and I was similarly frustrated by its failure to make use of the BEST space though I recognize that they dodged potential compatibility issues by avoiding the area where a front derailleur might hang or a tipple chainring might be running.
I don't run either of those so subsequent frame bags have been custom with a request not to shortcut the bottom of the triangle. I should note though, that my timing chain has worn a hole in one frame bag on my tandem so look out for similar issues if you go that route.
As a side note: My wife runs a frame bag on her Pugsley and the extra space afforded by the wider bottom bracket is similarly valuable but the wider bag is not so appreciated along the top tube.
I don't run either of those so subsequent frame bags have been custom with a request not to shortcut the bottom of the triangle. I should note though, that my timing chain has worn a hole in one frame bag on my tandem so look out for similar issues if you go that route.
As a side note: My wife runs a frame bag on her Pugsley and the extra space afforded by the wider bottom bracket is similarly valuable but the wider bag is not so appreciated along the top tube.
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I use the Wolftooth B-Rad to mount a roll-top bag below the water bottle on my seat tube.
The Wolftooth system is an adapter that mounts to the bottle bosses, and provides alternative mounting locations. I use it to shift the seat tube bottle cage up higher on the frame, creating space below for a bag. I am using the B-rad roll-top bag, which has a velcro strap that wraps around the mounting adapter to secure the bag, so it doesn't have to wrap around the frame tube. The only point of contact with the frame is the bottle bosses. On a 54cm road frame I have enough room for both a bottle and bag on the seat tube, and a standard bottle cage on the down tube.
I don't have a photo of my bike with this setup handy, but here is a google image search showing a similar setup on what looks like a very compact frame (and a 3rd bag mounted to the bottom side of the downtube):
The Wolftooth system is an adapter that mounts to the bottle bosses, and provides alternative mounting locations. I use it to shift the seat tube bottle cage up higher on the frame, creating space below for a bag. I am using the B-rad roll-top bag, which has a velcro strap that wraps around the mounting adapter to secure the bag, so it doesn't have to wrap around the frame tube. The only point of contact with the frame is the bottle bosses. On a 54cm road frame I have enough room for both a bottle and bag on the seat tube, and a standard bottle cage on the down tube.
I don't have a photo of my bike with this setup handy, but here is a google image search showing a similar setup on what looks like a very compact frame (and a 3rd bag mounted to the bottom side of the downtube):

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Also worth noting that this mounting location can be a bit tricky with front derailleurs, and also may not work on more compact geometry road bikes. I run a 1x drivetrain on my bike and it's a 54cm CX geometry. I have plenty of room, but the bag is very close to the chain ring. It's a little tricky to pull the seat tube bottle out of the cage - so I've gotten in the habit of emptying the down tube bottle entirely, then switching the two, so I'm only grabbing water from the down tube location.
I have always found seat bags to be annoying, so this was an easy solution for me.
I have always found seat bags to be annoying, so this was an easy solution for me.
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It's no good for small, loose items, but the Occam Apex strap with BOA ratchet is a pretty cool way to attach stuff anywhere on your frame. You can wrap your spare tube around the other items and then strap on the whole bundle at the location indicated, or elsewhere. The biggest drawback I see to that location is you're pretty limited in width, to not interfere with the crank or derailleur.
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this, for the roadie...
Noted the posts with the Occam Strap and Wolftooth system, but then would still have to come up with 'container,bag,sack' to hold the stuff...
can't give up a bottle cage/mount for the WOlftoothStrap/ plate - so also need the 'extension' bar ? - too much for me...
I'm a bit more DYI kinda... I use double sided velcro for lots of things... backpacking, carrying photo gear, etc...
If I go with an additional mount, just for the mtb/tube (also using the Dakine Gripper for the loose stuff...) I'll go with double sided velcro for the tube...
double sided velcro - 2 inch - 4 ft
Plenty for both my mtbs...
Ride On
Yuri
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I use the "3 slot mounting base" and am able to mount a water bottle cage to the top half, and the strap/accessory mount to the lower half. It all attaches to the bike using the two bolts on the seat tube. The roll-top bag attaches to the plate with a velcro strap, so nothing is actually touching the frame.
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#22
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Adipura do a couple of under downtube bags, 1.2 and 1.8L. I was tempted but don't think they'll play nicely with external cables.
https://www.apidura.com/shop/accessories/
https://www.apidura.com/shop/accessories/