This is the best explanation of a Z-drag and its use. I like that you started simply with rope, 2 prussik loops and 4 carabiners. I come back now and then to review this just in case.
Рік тому+3
I was looking for a while for this kind of video no pulley, DIY low wait and space to my solo ADV trips with a heavy bike. thank you.
GM climbing makes light weight aluminum pulleys you can buy on amazon. I ride in Colorado and have carried a rope and pulley for several years after spending over an hour with 2 of us trying to get a KTM 300 10 ft back up the mountain to the trail. It was steep and loose terrain. I recovered my KTM 300 yesterday by myself with the system and only 1 pulley (just ordered another) I was unable to stand the bike up though due to no prusik loop to lock it so I drug it up by the rear wheel pulling on the rope and tugger strap since it was pointed down hill. Thanks for the video and great idea, prusik loop would have been real handy yesterday!
I could be wrong, but I think that is a 2:1 pulley system with extra loops, because the carabiners at each end are mounted at the same point. Proof would be on measuring the amount of rope pulled compared to the distance the bike moves.
great explanation - I'm keen to build a kit to carry with me, and would like it as light weight as possible. So, for the sake of my shopping list, what proportion of the total load must each element of the solution be able to bear (let's exclude inefficiency in the system and drag if the bike is not on its wheels): - Main line - Caribiners - Prussic line Thanks
Are you not loading that thin front prussik loop with at least half the total force involved? I can understand using a prussik as a brake (that's your rear prussik) and that's fine, but I'd be concerned about the front one's ability to handle a possibly dynamic heavy load.
The ratchet prusik ( attached to the bike) is the one that will take the dynamic load, not the haul prusik. The simple solution here is to just use two prusiks at the bike end.
I am really sure this would work as you have shown. Can you give us an update? Have you had a chance to use it in the 4 years since you made the video?
There are some mistakes on how you are figuring your mechanical advantage and the rigging of the system. Firstly, because you are pulling toward the load and not towards the anchor, this configuration results on putting the whole load on your prusik. That is, the tree is no longer your anchor but the thin prusik cord is, and it could fail. Next, you are not taking into account adding tensions or sustracting the friction coefficient of a carabiner. A carabiner diminishes the efficiency of the system by about 55% at each tension point, in contrast to a pulley which diminishes only by 10% at each tension point. When I add the numbers your system as it is rigged with 4 carabiners will result in about .75 net (not theoretical) mechanical advantage, which is less than a 1:1. Use pulleys and pull from the anchor; it will be much safer and much more efficient.
Not only better but the only way to go. As it is, you are working against yourself. You would be better off just pushing the bike, as you are at least .25 disadvantage.
Around eighty feet, I think. You'll need four times the amount of rope for every foot your bike is away from the anchor point and another three or four feet to wrap around the anchor and to tie it off.
It's definitely a great idea. I've tried this with pulleys and even with those the drag is tremendous and actually rescuing anything heavy doesn't work out as easily as i hoped. Have you been successful using it in an actual rescue?
This is the best explanation of a Z-drag and its use. I like that you started simply with rope, 2 prussik loops and 4 carabiners. I come back now and then to review this just in case.
I was looking for a while for this kind of video no pulley, DIY low wait and space to my solo ADV trips with a heavy bike. thank you.
GM climbing makes light weight aluminum pulleys you can buy on amazon. I ride in Colorado and have carried a rope and pulley for several years after spending over an hour with 2 of us trying to get a KTM 300 10 ft back up the mountain to the trail. It was steep and loose terrain. I recovered my KTM 300 yesterday by myself with the system and only 1 pulley (just ordered another) I was unable to stand the bike up though due to no prusik loop to lock it so I drug it up by the rear wheel pulling on the rope and tugger strap since it was pointed down hill. Thanks for the video and great idea, prusik loop would have been real handy yesterday!
Yeah, I should get some of those pulleys! :)
Thank you very much that is brilliant, and every person should know how to do it
Ohh... nice . merci. super. it's going to be used for shure. thanks a lot.
Very impressive thanks for sharing will have to learn all those knots
I could be wrong, but I think that is a 2:1 pulley system with extra loops, because the carabiners at each end are mounted at the same point. Proof would be on measuring the amount of rope pulled compared to the distance the bike moves.
Nicely done!
Great video thanks
I'm not sure what to call it so I'll say, it looks like a good homemade emergency rope pully system. I'm looking for solutions like this.
A good cheap system. Thanks
Love it! I'm makin one!
Great vid man!
Good idea. It is smart to try it in your yard before needing it. Thanks for sharing.
Welcome :)
great explanation - I'm keen to build a kit to carry with me, and would like it as light weight as possible. So, for the sake of my shopping list, what proportion of the total load must each element of the solution be able to bear (let's exclude inefficiency in the system and drag if the bike is not on its wheels):
- Main line
- Caribiners
- Prussic line
Thanks
nice work
Thanks :)
EXACTLY WHAT I NEEDED. THANK YOU.
cool thanks for sharing
Excellent. Well done, cheers and thank s.
Great Job, Thanks
Nice riggin.
Nice!
Are you not loading that thin front prussik loop with at least half the total force involved? I can understand using a prussik as a brake (that's your rear prussik) and that's fine, but I'd be concerned about the front one's ability to handle a possibly dynamic heavy load.
I think you're right. I mention in the description, "Probably should use something thicker for the Prusiks"
The ratchet prusik ( attached to the bike) is the one that will take the dynamic load, not the haul prusik. The simple solution here is to just use two prusiks at the bike end.
Interessant! 👏👍🇨🇭
I am really sure this would work as you have shown. Can you give us an update? Have you had a chance to use it in the 4 years since you made the video?
Wow. you could haul a bike up a cliff with that much mechanical advantage. Very nice.
thank you
There are some mistakes on how you are figuring your mechanical advantage and the rigging of the system. Firstly, because you are pulling toward the load and not towards the anchor, this configuration results on putting the whole load on your prusik. That is, the tree is no longer your anchor but the thin prusik cord is, and it could fail.
Next, you are not taking into account adding tensions or sustracting the friction coefficient of a carabiner. A carabiner diminishes the efficiency of the system by about 55% at each tension point, in contrast to a pulley which diminishes only by 10% at each tension point. When I add the numbers your system as it is rigged with 4 carabiners will result in about .75 net (not theoretical) mechanical advantage, which is less than a 1:1. Use pulleys and pull from the anchor; it will be much safer and much more efficient.
Thanks for the feedback. Not relying on the prussik and using pulleys is much better.
Not only better but the only way to go. As it is, you are working against yourself. You would be better off just pushing the bike, as you are at least .25 disadvantage.
You don’t have many friends huh?
Very cool. How much rope are you using here?
Around eighty feet, I think. You'll need four times the amount of rope for every foot your bike is away from the anchor point and another three or four feet to wrap around the anchor and to tie it off.
GOD BLESS YOU
It's definitely a great idea. I've tried this with pulleys and even with those the drag is tremendous and actually rescuing anything heavy doesn't work out as easily as i hoped.
Have you been successful using it in an actual rescue?
Forgot to say thank you for taking the time to share!
where did you get the grab handle on front of the bike ?
I think it's Giant Loop brand, from Slavens Racing maybe?
You also have to account 10% weight as friction
👍
Brilliant but oopsie… there are no trees in the desert
Near ledges there are plenty of bomber rocks!
A: What's a "... 4 to 1 Rove to Disadvantage...?"
Q: I'll take "Proofreading" for $1,000, Als.
Or you can buy BestRest Motorcycle Recovery System for $180.... rofl
Good video! Thanx!
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