Looking at the Osprey raptor 10 or 14 litre hydration packs. Does anyone have any experience with these, and can suggest whether there is a significant advantage in the extra capacity offered by the 14? Will be using it for day-long rides as well as trail centres, so something that can carry tools, phone, food, an extra layer while still being light and comfortable to wear is essential.
I've got a Cambelbak MULE which has about 11l of pack capacity. I found that this is quite enough for day-long rides, far from any roads. I packed:
- spare tube
- patch kit
- a spare tyre sometimes
- some food (energy bars and similar low-volume-high-yield food)
- small first aid kit
- rain jacket
- a warm undershirt if necessary
My fullface helmet could be strapped to the outside on long ascents. If you're feeling adventurous, you'll even get full size shin/knee guards strapped to the side of the pack, but then it will be a little unwieldy.
If you don't need to attach your helmet to the pack, you can roll up clothes and attach them around the sides and upper edge of the pack using the four compression straps.
Beware of one thing: If you fill the bladder up to the maximum, the back of the pack will bulge out, reducing comfort.
Alternative suggestion - don't take a pack. They make your back hot and sweaty and raise your center of mass.
Instead I carry two water bottles, so 1.5 L of liquid, enough for ~3 hours of normal weather. My toolbag and one tube is velcro strapped to the frame along with the frame pump.
I wear a generic road top with three pockets in the lower back. Second spare tube, first aid box, thermal blanket, and food goes in there, along with a tiny rainjacket and tube scarf. I wear thin but full gloves and my training music player sits inside the left glove.
My phone and a USB battery is in a top tube bag attached to the stem, and my gopro is on the front of the stem for powering by the battery.
That said I don't carry a spare tyre or normal shoes.
I do try to lighten my pockets.... I only carry one front door key not the whole lot, etc.
Answer: consider distributing your load onto the bike frame, not the rider.
It entirely depends on where you ride, weather conditions and how long you are out for. Your tolerance for discomfort an risk comes into it. e.g. If you are one hour riding time from the nearest road and you bike breaks, you break an arm, or leg......
Bigger pack carries more stuff. You want to carry the smallest amount possible, but still have room for the food, water tools, first aid kit, kitchen sink and warm cloths you need (not want). Note that if you have bag bigger than needed you will fill it with stuff you don't need.
A smaller backpack is better, provided everything fits in. It sits better on your back and is less obtrusive, moving around less and usually more comfortable. therefore get the smallest that will carry the stuff you need.
The 10 liter has enough room for your tools and also a coat, a snack or two, and probably a shirt and a few other small items. If you're not worried about bringing much else, you'll probably be fine with the 10. Even if you are going to need to bring an entire change of clothes or more food, the 14 liter isn't really going to make much of a difference, in that case you'd be better off starting to think about 18 or 20 liters.