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Johnsfwdbent
recumbent enthusiast

USA
116 Posts

Posted - 12/13/2016 :  14:06:47  Show Profile  Reply with Quote
https://drive.google.com/open?id=0B1AaSnhDDhaHUE1sN2dVakhpSmc

I built a bike over the weekend!

12" seat pan
20" bb
10 degree seat angle
57" wheel base
69 degree head tube 4" trail
26" (559 x 32) front wheel
700c x 28 rear wheel
Top of handle bar 31"
Chromoly and aluminum construction
Weight about 30 lbs

No brakes yet so old shoes for stopping
So far top speed 30.5 mph
Handles just as i expected!

John

Speedbiker
human power expert

USA
3760 Posts

Posted - 12/13/2016 :  17:15:23  Show Profile  Reply with Quote
Fine job, sir! And a beautiful backdrop, too.
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Johnsfwdbent
recumbent enthusiast

USA
116 Posts

Posted - 12/13/2016 :  19:20:12  Show Profile  Reply with Quote
Thanks Speedbiker!
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Runxner
recumbent enthusiast

USA
441 Posts

Posted - 12/13/2016 :  20:38:07  Show Profile  Reply with Quote
700/26! how tall are ya?

Team Low-Life
Lowracer Test Pilot/Evangelist
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Balor
recumbent guru

Russia
514 Posts

Posted - 12/14/2016 :  00:24:53  Show Profile  Reply with Quote
It does look beautiful in a rugged way! And light (relatively :)).
30.5 mph with shoes for brakes? It does not bode well for aerodynamics! (If you know what I mean, he-he-he).
Anyway, now I think it WILL be faster than Nocom, just make sure you get a set of really good tires.
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Speedbiker
human power expert

USA
3760 Posts

Posted - 12/14/2016 :  03:38:15  Show Profile  Reply with Quote
Some people will build a bike, and then talk about it for a year. Others will talk about it for a year, and then they might build it.
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Speedbiker
human power expert

USA
3760 Posts

Posted - 12/14/2016 :  03:41:12  Show Profile  Reply with Quote
Faster than a NoCom? Ha ha ha, not yet. As John knows very well, 30.5 is a good time trial speed for a NoCom(at least mine), not a good top speed. With development I'm sure John's bike will be plenty fast.
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Balor
recumbent guru

Russia
514 Posts

Posted - 12/14/2016 :  04:12:06  Show Profile  Reply with Quote
quote:
Originally posted by Speedbiker

Faster than a NoCom? Ha ha ha, not yet. As John knows very well, 30.5 is a good time trial speed for a NoCom(at least mine), not a good top speed. With development I'm sure John's bike will be plenty fast.



Well, with no brakes MY top speed would be 10 mph at best, hehe. Good brakes make you faster :).
Anyway, I've meant that he'd be faster on this MBB than on NoCom because he'd be able to output more power on his MBB, not that he has better aerodynamics. (But I think they are pretty close now)
But that is just personal, if somewhat informed opinion, right.
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alevand
human power expert

USA
2936 Posts

Posted - 12/14/2016 :  04:44:22  Show Profile  Visit alevand's Homepage  Reply with Quote
One weekend! Looks good, John. Its been months and I'm still tinkering and talking. Brakes are overrated anyway, unless your headed into the path of an on coming car. Aaron, Id say by the photo he's over 6 foot, maybe 6-3, almost Warrens height. I probably have the same amount of thigh scrub on mbb-vps as the photo. Looks like nice riding weather.

C:
Tony Levand
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Johnsfwdbent
recumbent enthusiast

USA
116 Posts

Posted - 12/14/2016 :  18:42:56  Show Profile  Reply with Quote
Runxner, I'm 6'6" tall like Warren .
I was going to go dual 700c, but with the 26 I was able to lower the seat 2 more inches.
The only thing now is that I can't use my 700c power tap wheel, oh well.

Speed wise I think the same bike in twisted chain or rwd would be slightly faster, only because you could go with narrow gunner bars, and not have your hands out in the breeze!
Although it is easier to run.a solid wheel disc on a mbb with the wide handle bar!

John
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Speedbiker
human power expert

USA
3760 Posts

Posted - 12/14/2016 :  19:04:30  Show Profile  Reply with Quote
My exact thought about hand and arm position, John. Pulling your arms in really helps speed. But, does the mbb's efficient drive make up for narrow hannd position aerodynamics. We'll see when you get your bike dialed in.
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warren
human power expert

USA
6118 Posts

Posted - 12/14/2016 :  19:52:42  Show Profile  Visit warren's Homepage  Reply with Quote
Looks great John!
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alevand
human power expert

USA
2936 Posts

Posted - 12/15/2016 :  04:11:47  Show Profile  Visit alevand's Homepage  Reply with Quote
Tom Traylor used aerobars, I can't find his site anymore where he explains this. I have zero experience on MBBs. I was planning to have arms stretched out on the sides.


C:
Tony Levand

Edited by - alevand on 12/15/2016 04:13:25
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Speedbiker
human power expert

USA
3760 Posts

Posted - 12/15/2016 :  05:47:42  Show Profile  Reply with Quote
Charlie used narrow aerobars on the MBB prototype we developed for Cruzbike. Of couse, like John's bike the seat was very laid back. Essentially, this locks your arms straight. Okay for going straight, terrible for turning. In essence, you steer with your elbows. It was hateful and dangerous to ride, and we didn't see an increase in speed. Probably because you still had to position your arms in such a way that you could still steer. So he switched back to the wide bars. Look up the results from the 2015 Sebring race to see how well that worked.
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Johnsfwdbent
recumbent enthusiast

USA
116 Posts

Posted - 12/15/2016 :  19:42:31  Show Profile  Reply with Quote
Thanks Warren
Tony I think locking my arms in looks scary, like Speedbiker said, you would still have to have your arms, hands in the wind.
Thanks Jerry, pads in shorts and arm protection is not a bad idea, I tried to juggle A couple of water bottles on my m5 when one slipped out of my hand and I tried to catch it and slid on my side at 20+mph .... ouch!,

John
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alevand
human power expert

USA
2936 Posts

Posted - 12/17/2016 :  05:48:10  Show Profile  Visit alevand's Homepage  Reply with Quote
How does the MBB compare to the M5?

C:
Tony Levand
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Johnsfwdbent
recumbent enthusiast

USA
116 Posts

Posted - 12/17/2016 :  08:56:00  Show Profile  Reply with Quote
Tony, this MBB is faster than the M5.
The seat is more laid back and less frame work hanging low under the mbb seat.
The M5 451 wheel rolls slower then a 559. Switched it to a 559 but a 64 degree head tube now, pretty sensitive!!
Also that long chain flopping around on the M5 (340 links) has to be using some extra power!
Need more miles on the MBB to see just how much faster.

Thx
John
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Balor
recumbent guru

Russia
514 Posts

Posted - 12/17/2016 :  12:35:08  Show Profile  Reply with Quote
quote:
Originally posted by alevand

Tom Traylor used aerobars, I can't find his site anymore where he explains this. I have zero experience on MBBs. I was planning to have arms stretched out on the sides.


C:
Tony Levand



It is quite possible to have a very narrow cockpit on MBB, Larry Oslund from Cruzbike uses THIS puny stick for controls:



He does admit that his max power output is limited this way (because any pedalling style but working one leg aganst the other in perfect synchrony will likely rip handlebars out of his hands), but given aero benefits, he does not really NEED that much watts to be damn fast on the flats:

https://www.strava.com/activities/356619174/analysis

But climbing and sprinting suffers, as well as general 'controllability', due to steering inertia inherent in MBB platform and extremely low leverage to control it (except using leg feedback. Cannot do it myself yet - I think this is only for the gifted with good kinaesthetics).

Edited by - Balor on 12/17/2016 12:36:58
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Speedbiker
human power expert

USA
3760 Posts

Posted - 12/17/2016 :  17:31:31  Show Profile  Reply with Quote
Larry has won few(or none) races since he went to the narrow bars. His data on the oval test track show it is minimally faster, but as Balor says, anything above cruising power is a problem. I've worked hard on a more aero solution, but have yet to find one. Plus, there are faster formats that don't suffer some of the same problems inherent to MBBs, so I lost interest in trying.
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alevand
human power expert

USA
2936 Posts

Posted - 12/21/2016 :  09:39:30  Show Profile  Visit alevand's Homepage  Reply with Quote
John, What is the fastest you've gone down hill on an MBB?

C:
Tony Levand
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Balor
recumbent guru

Russia
514 Posts

Posted - 12/21/2016 :  13:05:01  Show Profile  Reply with Quote
quote:
Originally posted by alevand

John, What is the fastest you've gone down hill on an MBB?

C:
Tony Levand



It might be a good idea for you to browse Cruzbike forums, they have a lot of data about MBB behaviour.
Of course, there is a tendency to somewhat downplay the downsides due to tribalistic self-censoring, but usually you can read between the lines.
I tend to agree both MBB advocates and MBB opponents have good arguments in case of traditional designs.
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Johnsfwdbent
recumbent enthusiast

USA
116 Posts

Posted - 12/21/2016 :  15:21:42  Show Profile  Reply with Quote
Tony, I have had my other Mbb up to 48.1 mph, windy conditions and gravel on the road, so that was as fast as I wanted to go!!

John
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Speedbiker
human power expert

USA
3760 Posts

Posted - 12/21/2016 :  17:18:26  Show Profile  Reply with Quote
Charlie hit 45 on his modified Vendetta. I was doing 46 on the NoCom. We were both coasting with no desire to go faster.
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Balor
recumbent guru

Russia
514 Posts

Posted - 12/22/2016 :  04:54:57  Show Profile  Reply with Quote
quote:
Originally posted by Speedbiker

I didn't hear John asking for help on his handling....

Charlie hit 45 on his modified Vendetta. I was doing 46 on the NoCom. We were both coasting with no desire to go faster.



Well, it gets easier, but it never gets completely 'effortless', it seems. You need to stay 'on edge'.
Some may actually like it, riding that edge I suppose. I do not, but I do like the effectiveness, even if it is merely 'perceived' effectiveness like you claim from your experience.
We'll see.
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Speedbiker
human power expert

USA
3760 Posts

Posted - 12/22/2016 :  09:49:17  Show Profile  Reply with Quote
Hey, how did my reply to Balor get put ahead of his post?
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Balor
recumbent guru

Russia
514 Posts

Posted - 12/22/2016 :  10:41:36  Show Profile  Reply with Quote
Let me explain Speedbiker, even as some messages got deleted it seems.

Like I already stated in an other discussion, elite athletes are statistical outliers when it comes to pain, fear and stress tolerance (as well as other obvious things)- otherwise they would not be elite.
This is exactly why their personal opinion on such things is not exactly helpful for 'mere mortals', and I came to recumbent ultracycling because I don't like pain, but I need a way to offload a lot of calories in a way that is not another form of torture (mental) in itself like gyms to stay healthy. I'm also rather awkward, and while I'm ok with thought that my hobby may get me killed someday (drunk drivers are least discriminating people this side of multiculturalist Utopia, hah), I AM 'easily scared', and it I have to account for that when I plan my builds and trips.

MBB is fast, but ultimately uncomfortable - this is what a lot of 'mere mortals' from other forums claim, so long as they are not biased one way or an other. My own experience seems to correlate with that, I just blame other reasons than 'pedal feedback' and have other reasons to credit for effectiveness - they might be wrong, but I'll be trying to put them to test and sharing the results.

So, yea, sometimes 'you are too good to agree with' may be a genuine argument. Just please stop seeing every perceived disagreement with you as personal attack on your status and replying in kind with acidic sarcasm - it does make it hard to filter out genuine contributions unless moderation kicks in.
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