[vitox]

you kiwis!

 

[EVRAC]

Awesome.

 

[luelling]

Richie has been running a similar arrangement for a couple of years now. Had to get rid of the smaller sprockets on the primary drive as they were eating chains and gears.

I wish I was creative and mechanically inclined enough to make my own bike. I'm envious of BCD. Shoulda majored in Mechanical/Manufacturing like all my friends....I had to go and be a computer geek

 

[Ridge Rider]

I'm just not sure why you'd want to use twice as many sprockets and require both ends to shift simultaneously for the same range and steps as a one at a time rig.
I guess the front shifting may be a little better if the ratios are tight, but generally shifting both at once would seem likely to eliminate this advantage.
I'm sure you could use a standard shifter with a leverage multiplier at the business end. That Italian one seems to have alternating cogs. Is it a 21 speed or an 11?
BCD you were a gearbox pioneer in the late 90's but gave it away for the area suspension diversion . With things like over 80% of poll respondants saying they would prefer to buy a gearbox bike on Farkin.net recently you should not be chucking gearboxes in favour of big wheels. Big wheels are good but if you lose some swingarm angle the tradeoffs on big bump performance, pedalling and braking may lose their advantage. By all means do both, but don't walk away from the real performance and reliability gains of gearbox layout.

This thread is about the Italian gearbox. I am just describing how the Italian system works.

Go to http://www.nosmokemtb.it/

Switch to the english version of the site and view the videos and read the description. It is an 11 speed. The advantage of using a "one at a time rig" is that the chain is aligned at all times and the shifter becomes simpler and the whole arrangement can become more compact. As well the steps between ratios can be almost the same through the whole range of gears.

 

[ÆX]

bcd cogbox

1> 12x19 16.86 14.35% 52.98 7.60 4' 4.98" 1195.99 1:0.63
2> 13x18 19.28 14.03% 60.58 8.50 5' 0.58" 1045.88 1:0.72
3> 14x17 21.99 13.84% 69.08 9.56 5' 9.08" 917.22 1:0.82
4> 15x16 25.03 13.78% 78.64 10.83 6' 6.64" 805.72 1:0.94
5> 16x15 28.48 13.84% 89.47 12.38 7' 5.47" 708.15 1:1.07
6> 17x14 32.42 14.03% 101.85 14.29 8' 5.85" 622.06 1:1.21
7> 18x13 36.97 14.35% 116.14 16.67 9' 8.14" 545.54 1:1.38
8> 19x12 42.27 0.00% 132.81 0.00 11' 0.81" 477.07 1:1.58

DH bike

1> 42x25 44.86 8.70% 140.92 12.25 11' 8.92" 449.62 1:1.68
2> 42x23 48.76 9.52% 153.17 14.59 12' 9.17" 413.65 1:1.83
3> 42x21 53.40 10.53% 167.76 17.66 13'11.76" 377.68 1:2.00
4> 42x19 59.02 11.76% 185.42 21.81 15' 5.42" 341.71 1:2.21
5> 42x17 65.96 13.33% 207.23 27.63 17' 3.23" 305.74 1:2.47
6> 42x15 74.76 7.14% 234.87 16.78 19' 6.87" 269.77 1:2.80
7> 42x14 80.10 7.69% 251.64 19.36 20'11.64" 251.79 1:3.00
8> 42x13 86.26 8.33% 271.00 22.58 22' 7.00" 233.80 1:3.23
9> 42x12 93.45 0.00% 293.58 0.00 24' 5.58" 215.82 1:3.50

XC 11-32

1> 22x32 18.36 14.29% 57.67 8.24 4' 9.67" 1098.71 1:0.69
2> 22x28 20.98 16.67% 65.91 10.98 5' 5.91" 961.37 1:0.79
3> 22x24 24.47 9.09% 76.89 6.99 6' 4.89" 824.03 1:0.92
4> 32x32 26.70 4.76% 83.88 3.99 6'11.88" 755.36 1:1.00
5> 22x21 27.97 9.09% 87.87 7.99 7' 3.87" 721.03 1:1.05
6> 32x28 30.51 6.94% 95.86 6.66 7'11.86" 660.94 1:1.14
7> 22x18 32.63 7.39% 102.52 7.57 8' 6.52" 618.02 1:1.22
8> 42x32 35.04 1.59% 110.09 1.75 9' 2.09" 575.51 1:1.31
9> 32x24 35.60 3.13% 111.84 3.50 9' 3.84" 566.52 1:1.33
10> 22x16 36.71 9.09% 115.34 10.49 9' 7.34" 549.35 1:1.38
11> 42x28 40.05 1.59% 125.82 2.00 10' 5.82" 503.57 1:1.50
12> 32x21 40.69 3.13% 127.82 3.99 10' 7.82" 495.71 1:1.52
13> 22x14 41.96 11.36% 131.81 14.98 10'11.81" 480.68 1:1.57
14> 42x24 46.73 1.59% 146.79 2.33 12' 2.79" 431.63 1:1.75
15> 32x18 47.47 3.13% 149.12 4.66 12' 5.12" 424.89 1:1.78
16> 22x12 48.95 9.09% 153.78 13.98 12' 9.78" 412.01 1:1.83
17> 42x21 53.40 0.00% 167.76 0.00 13'11.76" 377.68 1:2.00
18> 32x16 53.40 0.00% 167.76 0.00 13'11.76" 377.68 1:2.00
19> 22x11 53.40 14.29% 167.76 23.97 13'11.76" 377.68 1:2.00
20> 32x14 61.03 2.08% 191.73 3.99 15'11.73" 330.47 1:2.29
21> 42x18 62.30 12.50% 195.72 24.47 16' 3.72" 323.73 1:2.33
22> 42x16 70.09 1.59% 220.19 3.50 18' 4.19" 287.76 1:2.62
23> 32x12 71.20 9.09% 223.68 20.33 18' 7.68" 283.26 1:2.67
24> 32x11 77.67 3.12% 244.02 7.63 20' 4.02" 259.66 1:2.91
25> 42x14 80.10 16.67% 251.64 41.94 20'11.64" 251.79 1:3.00
26> 42x12 93.45 9.09% 293.58 26.69 24' 5.58" 215.82 1:3.50
27> 42x11 101.95 0.00% 320.27 0.00 26' 8.27" 197.83 1:3.82



calculations from - http://www.panix.com/~jbarrm/cycal/cycal.30f.html

 

[EVRAC]

From the nosmokemtb site:

The Phaser is a prototype of which only two types exist so it is not possible to make a comparison with other similar systems because they are not very popular and have a very little distribution. The taiwanese V-Boxx of SR SunTour and the G-Boxx di Karl Nicolai, for the DH and the freeriding, have been relised few weeks ago. The system Honda of Shinja, Yashiaki, Takeshi, Naoki ( patent US 2004/0192480 A1 ), is used alone on the bicycles of the G-Cross team. Petespeed (inventor Petrus Van Der Linde, patent WO 02/08050 A1 , acquired a year ago from the Hayes) and Shimano (inventor Paul Thomasberg, patent EP 1 580 114 A2 ) are not in commerce.

Wait a sec, Shimano has a diab patent? Can someone look that up?

 

[ÆX]

I'm Big wheels are good but if you lose some swingarm angle the tradeoffs on big bump performance, pedalling and braking may lose their advantage. .....

can you draw a little expaination for me?

so you are talking about high pivot placement vs wheels size?

you guys freezing down there?

alex

 

[UncaJohn]

well i was doing 12-19 - tooth profiles cut down for quick shifts.
but i never got it to shift as fast as i wanted.

now with his patents its in the trash.

i think 29 wheels will progress DH far FAR FAR more!

Well Alex,
youre reffering to the oldest story about patents. If you have spend serious time on this project better check if the system is actually covered in the USA, or just talk to the guy.
Patents are a mess and i know that from first hand. My suspension system has been ripped by some major manufacturers and i can do just nothing (add on that the neverending conflict between the EU & US patent offices and you'll surelly get a.. headache)

UncaJohn

 

[ÆX]

Well Alex,
youre reffering to the oldest story about patents. If you have spend serious time on this project better check if the system is actually covered in the USA, or just talk to the guy.
Patents are a mess and i know that from first hand. My suspension system has been ripped by some major manufacturers and i can do just nothing (add on that the neverending conflict between the EU & US patent offices and you'll surelly get a.. headache)

UncaJohn

thanks for the truthful words.
If i was in a company to back my ideas......
If i could stay off these forums.......
If ..... well, i can't and don't.

Like i have said before i am not in it for a career.
I would like to make some money at it though.

making a cogbox like that would be very time consuming
still keeping gearbox frames out of reach for the racers.

that is why i am using the alfine. got one yesterday and
def like it better than the nexus.

thanks again, alex

 

[Nately27]

From the nosmokemtb site:

and Shimano (inventor Paul Thomasberg, patent EP 1 580 114 A2 ) are not in commerce.

Wait a sec, Shimano has a diab patent? Can someone look that up?

I was curious and looked it up for those that are interested: Shimanos DIAB.