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Richie104
12-31-2010, 12:15 PM
Hello again everyone,
I have another question for you all. I have been doing some research and trying to work out how heavy a completed tomahawk is. My research puts it somewhere between a road bike and a cross country bike. (But I might be miles out :)
Can you all help me out by giving me a rough estimate of the weight of your finished tomahawks? Or any completed Atomic Zombie bikes?
And if your really nice and want to super help you could even get it on the bathroom scales.
Thanks for the help
Richard.

Racer46
12-31-2010, 04:49 PM
I'll let you know sometime in late January. Mine should be done by then.

Odd Man Out
12-31-2010, 09:15 PM
Hello again everyone,
Can you all help me out by giving me a rough estimate of the weight of your finished tomahawks? Or any completed Atomic Zombie bikes?


All aluminum DeltaWolf = 43.6 pounds

John Lewis
01-01-2011, 04:34 AM
If I recall my SWB muffler tube Bentech came in at around 15kg about 33 lb with disk brakes. That should be similar to what the Tomahawk will weigh.
My LWB Marauder2 by comparison is round 21 kg or about 46 lb.

I seem to recall Brad or someone mentioning the weight at some time.

Weight is overrated unless you are riding a lot of hills. The best place to pare the weight is usually from the rider. That's true for me anyway.:jester:

John

Richie104
01-01-2011, 06:15 AM
Thanks for the help guys. I was just curious more than anything as to how a homebuilt recumbent compared to a factory built one. I also live right next to an extremely hill area (Harefield, England) and you have to ride through it before you get to see and country side. I just didn't want to be lugging a 40kg behemoth throughout it that was all.
Thanks again for the help.
Richard

MarcusPHagen
01-02-2011, 07:48 AM
I just didn't want to be lugging a 40kg behemoth throughout it that was all.
Thanks again for the help.

But Richard, just imagine how that poor recumbent feels about lugging YOU around! I'm certain you outweigh it.

Marcus

Racer46
01-29-2011, 10:57 PM
Using the unscientific method of placing the bike on my bathroom scale I come up with 37 pounds. I believe Brad said that his weighed 32 pounds. The extra weight on mine can be attributed to using 14 ga. tube instead of 16 ga. and my version of a sliding boom some of which is 1/8", Brad's design would be lighter.

trikeman
06-12-2011, 08:46 AM
Thanks for the help guys. I was just curious more than anything as to how a homebuilt recumbent compared to a factory built one. I also live right next to an extremely hill area (Harefield, England) and you have to ride through it before you get to see and country side. I just didn't want to be lugging a 40kg behemoth throughout it that was all.
Thanks again for the help.
Richard

I know this is an old thread, but I haven't been around too much for awhile, so I am trying to catch up. It is impossible to answer this question properly without knowing what components you are planning to use. The major advantage the manufacturers have over us is that they can order and weld special tubing at good prices. They also have a price advantage when they buy a lot of components, and we tend to use what we can find on old bikes. Bottom line is if you use the same components as a major manufacturer, the weight difference will be in the frame.

Now.. using my calibrated eyeball, I estimate a tomahawk to have about 8 and 1/2 feet of 1.5" 16 ga steel tube. The weight of 16 ga 1.5" steel is very close to 1.25 lbs/foot, which gives you a naked frame (no front fork etc) weight of a little over 10 pounds. Add in another pound for a headtube, and some rear dropouts and you have about 11 pounds.

For reference, a Bacchetta Corsa ( simple stick bike) steel frame weighs about 7.5 pounds, and the aluminum version tips the scales at about 5 pounds, naked, but these are simpler frames than the tomahawk mid-racer has.

Bottom line is a homebuilt tomahawk will most likely weigh 4 to 6 pounds more than a top of the line factory built if you use the same components. However, if you load it up with thrift store boat anchor components as most of us tend to do, you might get it to be 10 to even 20 pounds heavier.

A quick perusal of the weights of many road bike frames at weightweenies reveals that the average road bike frame weight is somewhere around 3 to 5 pounds, so once again, I would say your final tomahawk weight would be about 5 to 7 pounds heavier than a good road bike with the same level of components.

http://weightweenies.starbike.com/listings/components.php?type=roadframes

I think the Tomahawk is one of Brad's best designs to date. Its only a small weight penalty (and a huge cost savings) over something like a Lightning U2, and both have about the same aerodynamic advantage. I am seriously thinking of building a tomahawk as my re-entry into bike building.

As I recall (its been at least 4 years) when I built my Delta Wolf, it came in at around 55 pounds, but that was a very different design.

SirJoey
06-12-2011, 01:26 PM
WHOA! Is that TRIKEMAN?!! :D
Welcome back, man! Thought U fell offa the planet! :eek:

...or were abducted by :alien:



*** The **** Is My Shepherd! ***
http://img384.imageshack.us/img384/7131/sirjoeysigmedij1.gif
(Geezer & Bent Enthusiast At Large)

trikeman
06-12-2011, 02:20 PM
Nah. I just got bored with bike building and took some time off and concentrated on other things, like learning to play the ukulele, work etc. I even thought about building a few ukes ,.but started to get bored with that too. Didn't even ride much for a few years, but have started that up again 40 pounds heavier (ugh). Hankering to build another bike.

John Lewis
06-13-2011, 08:07 AM
Good to see you back trikeman.
Yes, my wolf came in at ~25kg which is as near as 55lbs.
Tomahawk will be way less. My Marauder was just under 20kg I think
and there's a lot more steel in that.

John

trikeman
06-13-2011, 09:03 AM
Good to see you back trikeman.
Yes, my wolf came in at ~25kg which is as near as 55lbs.
Tomahawk will be way less. My Marauder was just under 20kg I think
and there's a lot more steel in that.

John

Thanks John. As I posted a long time back, I think the suspension rear on the M2 adds about 5 pounds. The M1 as detailed in Brad and Kat's first book was my first love and what drew me to this site originally. That long Marauder front end and the steering gear probably add another 2-5 pounds. Even though the tomahawk has a slightly larger aero profile (mostly lower half of the wheels sticking down below your bottom), I think the weight savings and more manageable transport make it a very attractive alternative to the M1, let alone the M2. I suspect the tomahawk chain route is less efficient due to that extra power-side pulley on the headstock. If I do a tomahawk, I will most likely dispence with that pulley and route the chain more like a Baron or U2. I know that will cause it to hit the front wheel on tight turns, but I don't turn much. I'll put a chain tube on to keep the wheel clean.

While I am in weight-weenie mode, there is probably an extra pound in the rear fork design which the Tomahawk shares with the Warrior. I thought that design was brilliant enough to buy the Warrior plans just to see it in detail. It is so much easier for a beginner to build than trying to line up fork cut offs as in the M1 and HighRoller design, but it is a bit heavier.

I am guessing that OMO could build a very light Tomahawk if he wanted to use the evil metal and take all these things into account lol. So many choices when you build them yourself is part of what makes it fun.

trikeman
06-18-2011, 10:27 PM
Just for fun, I built a Tomahawk rearend today. I weighed it using the bathroom scale method and compared it to a heavy duty front fork I have, which includes the steerer tube, but no suspension. Interestly, they both weighed the same at 4.2 pounds.

http://forum.atomiczombie.com/showthread.php?5417-Built-a-Tomahawk-Rearend-Today&p=51598&highlight=built+a+tomahawk#post51598