Seat bag leg clearance

[KenGlman]

I've bicycle toured for many years, panniers on road bikes and a B.O.B. with a mountain bike. I'm thinking about outfitting my Mukluk and my mountain bike with bike packs, but I'm unsure about leg clearance for seat packs. I no longer use a seat bag to carry tools because they have a tendency to wear holes in the back of my shorts from repetitive contact between the back of my legs and the front of the bag. A seat bag for bikepacking is going to be much larger. How much clearance do you have with the seat bags? Any issues with them contacting your legs?

[MattL]

I have an Oveja Negra bag.  It brushes my legs, but much less than Carradice bags have in the past.  I have my saddle (WTB Volt) set all the way back, and that surely contributes.  If you have a different way to adjust the reach that can leave the saddle further forward on the rails, that may help (longer stem, setback post, longer top tube).

Still, I don't generally carry the big bag every day except, in this case, when I'm training for TD and am riding everywhere with the full load.

I'd say if normal seat bags (you mean like tube and tools sized?) bug your legs then the big bags will be much worse, much as you predict.

[KenGlman]

Thanks, MattL. Yes I mean normal seat bag, tools and tubes. Those cause quarter size abrasions on my (lycra) shorts near the backs of my thighs. I guess my options are to borrow a seat bag, if I can find one, and try it. If it doesn't work out for me then I need to consider using a rack with a dry bag.

[Long Haul Greg]

Ken,
    I purchased a Revelate Viscacha seat bag about a year ago for TD'12.  As soon as I got it, I started using it to carry my lunch and other kit on my daily commute to work.  It's 18 miles door-to-door, so I'd say last year's seat bag has easily logged over 8,000 miles since I've had it.  That bag has a very well-thought design feature in that there is a very pronounced taper from its full girth back aft to a very narrow width at the seat post.  I honestly don't even know its sitting just below inner-thigh level.  No contact with the seat bag and no telltale abrasions on any of my bike shorts.
    I highly recommend this particular bag.  I've been using a 15l syl-nylon drybag from Sea-to-Summit with the Revelate outer bag.  The S-t-S bag can be jam-packed and it's the right size/shape to simply slide right into the Revelate bag.

Best of luck. 

[Veetack]

I'm really concerned about tire clearance of the Viscacha for my bike. Revelate says you need 8" minimum from seat rails to tire, and 5" of post. I'm 5'7" and I ride a Giant Talon 29. The seat post is no issue, but I measured my rail to tire clearance at somewhere around 7.5" Is it really that big that it will take up all that room? I'd hate to order something that isn't going to fit my bike, as I already did that with the Tangle bag and forgot to return it for the exchange in time. If I don't have a full 8" will I get rub on the viscacha? should I just go with the Pika?

[Long Haul Greg]

    After reading your post, I measured my bag height at the seat post, and the minimum clearance between my bag and the rear tire.  My seat post measures 8.5 inches from top of the frame's seat tube to the seat rails.  There's another 2 inches from the top of the seat tube to the frame's top tube.  For the bag itself, it measures 7 inches tall, both at the seat post and the rest of its length.  It sits 1.0 inch below the seat rails because of the flare of the seat tube as it forms the clamp at the rails.  That put the overall length of the bag at 8.0 inches below the seat rails.  As you noted, 5 inches comes into play for the bag at the seat post.  Those five inches represent the length of seat tube you need to mount the velcro straps (2" straps 1" apart = 5 inches needed on the seat tube).  Keep in mind, the bag slants upwards from the seat tube, especially when the side straps are tightened.  As a result, my bag isn't anywhere near the rear tire.  There's a good 4 inches of clearance at the bag's closest point to the tire.

[Veetack]

What you're describing is exactly what I was thinking. Glad to know it. I'd hate to drop 130 dollars to find out I ordered the wrong thing.