Bivi bag and down jacket?

[AlexGold]

There was a recommendation in the 'newbie kit' thread recently along the same lines I'd been thinking, which was that in the summer (which is now, apparently) you could get away with a down jacket and no sleeping bag in a bivi bag. I'm trying to go ultra-mega-light for a 600k solo audax and was thinking along similar lines. I got one of those crazily cheap (and crazily yellow!) down gilets with a hood as mentioned in the 'bargain alert' thread, which I am taking to stay warm during food stops, and as a last resort to go over a base layer and jersey and under a waterproof if I am finding it crazy cold during any night riding sections. My thoughts were that maybe I can also get away with sleeping in it, along with full length merino top and bottoms.

The question is, is it doable? Just how cold does it get? I can carry a light sleeping bag, but even my lightest one will take up an additional 1/3rd of my saddle pack - obviously it's worth it if I won't sleep otherwise. Aiming to stop from 12-4 then get going, if that makes any difference to thoughts!

Input appreciated!

[Bearbonesnorm]

I'd say that even at this time of year you'll probably be cold. I'm assuming you're not going to be carrying a mat? ... which will compound the problem.

Think I'd be packing a thermal liner if I didn't have a lightweight summer bag.

Something like this:

http://www.outdoorgb.com/p/Sea_to_Summi ... mYQAvD_BwE

[ZeroDarkBivi]

You might get away with it depending on the other environmental factors; shelter from wind / rain, insulation from cold ground, etc. Personally I'd probably just ride on through, assuming it's not much more than 36 hrs. If you are knackered, 24 hr MacD, coffee, ear-plugs, 40 minute snooze in your seat, then wake up stimulated...

[AlexGold]

I'm assuming you're not going to be carrying a mat? ... which will compound the problem.

Current plan is Alpkit Numo (as it's small enough to not think twice)....but it's not much more insulation that nothing! Will check out the link, cheers!

[MuddyPete]

It depends whether you can sleep with cold feet. If you can, great!
If (like me) you can't you'll need to insulate your legs & feet with something, otherwise your body core will never push the warm blood down to your toes.

[AlexGold]

You might get away with it depending on the other environmental factors; shelter from wind / rain, insulation from cold ground, etc. Personally I'd probably just ride on through, assuming it's not much more than 36 hrs. If you are knackered, 24 hr MacD, coffee, ear-plugs, 40 minute snooze in your seat, then wake up stimulated...

That's option 2! I was going for the slightly more civilised version for my first 600, leaving the McD's naps for later. Also doing maybe the easiest one out there, so the extra weight is less of a problem.

I'm aware that ideally the answer is 'try it', but living in London with no garden it's harder than it sounds!

[AlexGold]

It depends whether you can sleep with cold feet. If you can, great!
If (like me) you can't you'll need to insulate your legs & feet with something, otherwise your body core will never push the warm blood down to your toes.

Plan would be mega thick 'Feet Heater' socks and merino long johns, tbh last time I did similar I had just the socks and my lightest bag (albeit in a tent - and I'll leave the underwear situation to everyone's imagination) and ended up taking the socks off as my feet were on fire!

[johnnystorm]

Depends what you want to achieve. I wanted to make sure I got out of the Great Basin early so just put on my down jacket and got in the bivi bag at midnight. By 3 am I was itching to get back on the bike!

[whitestone]

I did this on the YD300 a few weeks ago. My bivy kit was a SOL Escape bivy bag, a long sleeved thermal top and a PHD down vest. I got about 90mins sleep but it was enough to give me a rest. If you want a bit extra comfort then a Klymit x-frame inflatable mat would be fine at this time of year.

I find if you've got something dry (i.e. not sweaty) to change into then it's a big bonus.

[Chew]

Did something similar a few weeks back to test out some kit. Weather similar to today.

Bivi, silk liner, mat, thermals, down gillet. Managed to find a church porchway to camp in to get out of the wind.
With this I was on the edge of what was doable.

Depends on the overnight conditions of clear sky's and cold, or overcast and mild. Also finding an appropriate space to stop will be a bonus.

From my 600 earlier in the year 90 mins kip was plenty (I can nap others can't) and some time either side. I'd make sure you have a big meal before you stop, so your body has something to process while you 'rest'. I'd also push on later into the night, so if you're planning for a 4 hour stop it coincides with the early morning sun.

A down jacket, hat/buff, thermal leggings & thick socks and you'll be fine. After all you don't want to be too comfortable or you'll sleep for too long.

[bryanwadd]

A lot actually depends on you and whether you sleep warm or cold. Personally I sleep cold, something to do with my body's lack of insulation perhaps, and need a warm sleeping bag even in fairly mild weather.

[AlexGold]

Decision made! (subject to last minute change of mind)

I'm taking the sleeping bag, but not the down gilet. Forecast doesn't dip much below 15 degrees so could probably do without the bag, but it's already packed. Out for a test ride of the setup now