this looks like its going to be pretty sick
Sram Gearbox??????
- Thread starter NY_Star
- Start date
You know, this COULD also fire off a string of new products as well. Perhaps possibly a teeny, tiny rear cassette with an ubershort rear derailleur. Could mean less chain weight, less derailleur weight, less chance of smashing it on something(though I haven't had that happen in like...5 years?), may contain the necessary parts already to eliminate a chain guide...etc, etc.
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I'm running a 5 speed cassette on my DH bike and a 6 speed on my trail bike. Both on didhless single speed hubs, the 5 on a Hadley, the 6 on a Profile, both sweet hubs. Would be nice to have 12 gears on the trail bike like you mentioned. Use the front to double the range. I wonder if you could do it perfectly so you had 12 even gears, you'd have to change all rear gears to the other extreme when changing the front, but still be cool, not as cool as my Rohloff though.
it'd match up nice with an 8 speed alfine on the rear, you can at least dump all gears in one hit without pedalling, full twist forward on one hand, and back on the other, then you have another 8 gears.
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i'm so sure because i've ridden it, same with a lot of other people. it's going to be a very good thing for all mountain riding.
no more hucking a chain onto the BB shell is all it sounds like to me.
It looks like it will be something possibly by infinity transmissions (I hope). They've got the agreement signed with SRAM, and have quite a few patents out already for mechanical cvt's (both friction power split and ratcheting/oscillating).
Laird Gogins has his name on quite a few cvt patents, and hes the man behind infinity transmissions, developers of the (pictured) ratcheting/oscillating design seen on the link posted by thrillseeka.
Patents: (US)
7121160 ratcheting/osc
6779415 ratcheting/osc
5392664 Oscilating/friction?
Patent aps:
20020096002 similar ratcheting/osc design as the above two
Hopefully its something interesting, a 2 or 3 speed planetary gearset on the front, while convienent for bike design standards, is not revolutionary and has been done before by people with less of a stake in the industry, early in the 1900's in fact. I'm still not completely sure if its an indexed design, or a cvt design... beaverbiker could you answer that simple question - since you tested it and have an engineering background (I'm not asking for any design details, just whether it's cvt capable - ala the mandatory indexing put on honda's zero-max design transmission, or if its just strait up indexed, no cvt possibility)?
Laird Gogins has his name on quite a few cvt patents, and hes the man behind infinity transmissions, developers of the (pictured) ratcheting/oscillating design seen on the link posted by thrillseeka.
Patents: (US)
7121160 ratcheting/osc
6779415 ratcheting/osc
5392664 Oscilating/friction?
Patent aps:
20020096002 similar ratcheting/osc design as the above two
Hopefully its something interesting, a 2 or 3 speed planetary gearset on the front, while convienent for bike design standards, is not revolutionary and has been done before by people with less of a stake in the industry, early in the 1900's in fact. I'm still not completely sure if its an indexed design, or a cvt design... beaverbiker could you answer that simple question - since you tested it and have an engineering background (I'm not asking for any design details, just whether it's cvt capable - ala the mandatory indexing put on honda's zero-max design transmission, or if its just strait up indexed, no cvt possibility)?
If ISCG Tabs are required it should also fit with an e13 ISCG Adapter, or am i wrong, i do not know much AM Bikes with ISCG Taps thoughThis was at Interbike in Las Vegas.
The theories behind the idea are pure speculation.
Basically its a internal planetary gearing system for all bikes with ISDG mounts to hook it up to.
You will still have a rear derrailler and chain.
Every gear RPM will be reduced by about 50% and you will need less gears in the rear due to maximizing your drive forces VIA internal gearing system.
sorry man, my lips are sealed.
No you don't know me.
No I don't work for SRAM.
Yes I have ridden it.
Internal planetary gear on the crank actuated via normal shifter, just 2 gear options (about a 24/36 chainring equivalent), instant shift (you don't have to be pedaling), somewhat heavy, a little high on the "pedaling drag" at this point but hopefully they will work it out.
It was weird getting used to the instant shifts, I almost blew a knee out because I am used to it taking about 1/2 a revolution for the gear to actually change.
YES.. you will be riding one in the next year or so. It will be a staple for any dual ring AM bike.
This is the begining of the end for the drivetrain as we know it.
No I don't work for SRAM.
Yes I have ridden it.
Internal planetary gear on the crank actuated via normal shifter, just 2 gear options (about a 24/36 chainring equivalent), instant shift (you don't have to be pedaling), somewhat heavy, a little high on the "pedaling drag" at this point but hopefully they will work it out.
It was weird getting used to the instant shifts, I almost blew a knee out because I am used to it taking about 1/2 a revolution for the gear to actually change.
YES.. you will be riding one in the next year or so. It will be a staple for any dual ring AM bike.
This is the begining of the end for the drivetrain as we know it.
Why does "AM" keeping popping up? Lacking in the strength department? Can't take a hit?
Probably because if you normally run a single ring in the front, you won't care.
Actually, I guess if you think about it, AM/XC cranksets see more...torsional?... stress than DH stuff does. We don't need to stand up and CRANK up hills. We just need our stuff to take hits from rocks, and support the weight of our fat selves on harsh bottom outs/impacts.
But it sounds like they're directing this at the AM market...
But it sounds like they're directing this at the AM market...
I'll go out on a limb here and believe you even since this is your first post. You described what it accurately could be. I'm still not 100% convinced this is it, because it just seems so lame for the industry to take an innovation made over 100 years ago and reincarnate it with a fancy marketing strategy. I'll continue working on my design now that it seems that SRAM's groundbreaking turbo nutter extreme revolutionary cheech and chong white widow filled vaporizer beast of a novel design is just a simple BB mounted planetary transmission with 2 drive ratios (hell 3 ratios have been available in the past with similar designs, come on SRAM).
I wouldnt go so far as to say its the end of the drivetrain, as there will still be a.... drivetrain.... its just a slight alteration to the front transmission that seems to pop up every 20-30 years in biking and then fades away.
The marketing in biking lets me down anymore
Can't wait to find out the next DW bike tho haha
Something similar like the SRAM HammerSchmidt project, but technologically different: http://www.ridemonkey.com/forums/showthread.php?p=2999118#post2999118.
That B-box design looks clean. Do you have any link to more info on the mentioned magnetic clutch? How much heavier is it than a normal 2 ring setup?
Yeti, I´ve posted 2 links in this thread: http://www.ridemonkey.com/forums/showpost.php?p=2999118&postcount=244 (in German only). I have no more informations so far.
Wilhelm
may as well post this here for continuity. looks like a production unit:
I was just about to post that as well.
God dam! i need one so i can make a high pivot trail/AM bike!
hmmm as got me thinking!
hmmm as got me thinking!
Does it seem to you guys like a big bearing in the cranks/chainring region might cause some reliability problems. I love the idea and the unit looks nice and tight but the outer bearing has me worried.
yea this is true, but im not looking at it as a gearbox setup but as away of getting out of making up some funky frount derailleur for a high pivot AM bike with an idler.
plus there is not a suitable gearbox yet for trail/AM, well that i know of?
i think the best thing about gearboxes is that the output shaft placing can be optimized (high pivot) so you reduce squat from acceleration forces.
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