[dw]

I guess eveyone has their own nomenclature, but I've always known them as non circular gears. I was only able to find one reference to "variable pitch curve" on google. But back to variable pitch gears, we had this discussion at work as to if it was even possible. My VP and another senior engineer said they heard of somthing like that but never seen one. I managed to actually find one thanks to google. Ta da, a variable pitch gear.

http://128.146.169.39/Pages/Gear_Collection/Gear_Collection_Frame Pages/mech01.html

OK, so I found a couple books that I own and you can purchase that should help you out.

1) Encyclopedic dictionary of gears and Geearing, ISBN 0-07-059796-0

The definitions:
Pitch (Diametrical Pitch, Circular Pitch, and I would speculate Radial pitch although its not described and I have never heard the term, but by definition it should be accurate): In gear geometry, the distance between similar equally spaced tooth surfaces along a given line or curve.

Pitch radius/ pitch diameter/ pitch circle: In gear geometry, the curve of intersection of a pitch cylinder or cone and a plane of rotation.

By definition,Pitch radius is the "line" on which Pitch is measured. Pitch radius is a radial measurement of effective gear diameter, and pitch is a measurement of the distance between teeth as measured on the pitch radius. A pitch radius can vary, while maintining the same pitch, which is what most noncircular gears do, including the ones int eh Honda bike. That varying circular pitch gear is pretty nuts. Like the guys you work woth, thats the first example ot that Ive ever seen or heard of. I wonder if it has a constant pitch radius? Hard to tell by the picture.

2) Fundamentals of mechanical design (a standard Mech 1 textbook)

In the section describing standard and nonstandard gear systems, the difference between circular pitch, and pitch circle is pretty clearly illustrated.

Interesting stuff to say the least.

Later on!

Dave

 

[bizutch]

big...words....head....spin....hulk...no....understand.....gonna....barf.....wan't.......offf.........rriidddddeeeee.........nooooooowwwwwwwwwwww!!!!

 

[GravityFreakTJ]

big...words....head....spin....hulk...no....understand.....gonna....barf.....wan't.......offf.........rriidddddeeeee.........nooooooowwwwwwwwwwww!!!!

See dw,see! It ain't only me

 

[trialsmasta]

I think Bizutch sums it up best. We went from "variable pitch gear" to "variable pitch curve" to what the mechanical devices sourcebook calls "pitch curve variation" to some other books definitions of whats esentially pitch diameter. Don't take this the wrong way, It dosn't need to this complicated or technical. I might have learned some redundant terms today, but Honda uses non-circular gears and a ratcheting CVT, thats it in a nut shell.

 

[dw]

hells yeah man, thats it totally. I dont think there was ever any confusion as to how the system actually works, just a question of nomenclature. I tried to answer that for you as concisely as I could. No matter what, all usefulness of the system, and nomenclature to decribe individual components aside, the unit is a neat little thing!

dw

 

[davod]

Could you at least confirm that the Superboxx has nothing (at all) to do with the Rolhoff (or maybe it does)?

 

[bizutch]

hells yeah man, thats it totally. I dont think there was ever any confusion as to how the system actually works, just a question of nomenclature. I tried to answer that for you as concisely as I could. No matter what, all usefulness of the system, and nomenclature to decribe individual components aside, the unit is a neat little thing!

dw

so will the CVT see production??

 

[dw]

so will the CVT see production??

beats me man!

 

[dw]

Could you at least confirm that the Superboxx has nothing (at all) to do with the Rolhoff (or maybe it does)?

Superbox is just about as far away from Rohloff based as one idea could get.

 

[Echo]

Bombardier

Who makes Ski-Doo?

 

[trialsmasta]

Who makes Ski-Doo?

I belive Bombardier does. They have some pretty serious HP in their snow mobiles.

 

[davod]

When do people think gearboxes will start popping up on more trail-ish bikes?
(Well, I suppose there is already the Nicolai, but I mean when we start seeing prototypes from a variety of mfg's, like we are on DH bikes right now)

 

[Acadian]

Thanks to Jon Carr.

Versions:

Inside:

Chainline:

Japanese explanation:
http://www.honda.co.jp/HRC/closeup/index.html

 

[PAMS 25]

Japanese explanation:
http://www.honda.co.jp/HRC/closeup/index.html

Mister google is so intelligent : http://translate.google.com/translate?u=http://www.honda.co.jp/HRC/closeup/index.html&langpair=ja|en&hl=fr&ie=UTF8

 

[Duzitall]

http://www.honda.co.jp/HRC/team/g_cross/machine.html

RN01 team bike specs :heart:

Chris

 

[xy9ine]

so... was there ever a cvt in that bike, or was it always a derailleur in a box? 10kg (22lbs) wieght savings from proto 1 to 3!

 

[S.G.D]

wow, those pictures are rediculously cool.

and so is the 22lbs savings!!!

~SGD

 

[zedro]

Mister google is so intelligent : http://translate.google.com/translate?u=http://www.honda.co.jp/HRC/closeup/index.html&langpair=ja|en&hl=fr&ie=UTF8

As for the covered mission, adhesion and the rubbish of the mud which is in the midst of travelling 噛 you see and are packed, you prevent the trouble due to the penetration and the like of the water, furthermore the high pressure car washing after the travelling feel at rest and you are possible, actualize simple maintenance to do.

well, sometimes lol

 

[EVRAC]

Anyone else notice that unlike the Petespeed, the splined chainring is free to slide side to side. I guess it's supposed to "self-align", which might work fine on the workstand. On the petespeed it's controlled with the derailleur mech. With cornering and whipping your bike around, that sproket would slam from side to side and put horrible stresses on the chain. Maybe that's one of the reasons it makes so much noise on the racecourse. Looks like they missed an important detail.

 

[zedro]

Anyone else notice that unlike the Petespeed, the splined chainring is free to slide side to side. I guess it's supposed to "self-align", which might work fine on the workstand. On the petespeed it's controlled with the derailleur mech. With cornering and whipping your bike around, that sproket would slam from side to side and put horrible stresses on the chain. Maybe that's one of the reasons it makes so much noise on the racecourse. Looks like they missed an important detail.

i would of thought the opposite would happen in that case, that because of the friction caused by loading, the sproket would have a hard time moving side to side at all.

anyways, i doubt Honda would miss a detail that would render the tranny innoperable.

 

[Roasted]

It could work with the 'deraileur', as the deraileur moves side to side it simultaneously moves the sproket, keeping the alignment tight and not allow for slipage I wouldn't imagine Honda would just allow it to float.

 

[Ronny Grady]

It seems like the internal gearbox as a disruptive technology will kill the derailleur for at least high end DH bikes in the coming 2-5 years.

If this is the case, will all of the different rear suspension designs, FSR, VPP, dw-link, ect. become displaced by the single swingarm?

Am I right in thinking that any advantage of these advanced rear suspension links will be canceled out by a central gearbox where you want no chain-line growth?

 

[zedro]

Am I right in thinking that any advantage of these advanced rear suspension links will be canceled out by a central gearbox where you want no chain-line growth?

actually half of these designs dont even employ concentric (no growth) designs, either because they are harder to design for or seen as not as desirable (some like a slight growth).

these gearboxes inherantly dont solve all the suspension issues so you may see new 4 bar designs built around them, although the higher pivot ones (like say the GT) are pretty ideal IMO.

 

[dw]

It seems like the internal gearbox as a disruptive technology will kill the derailleur for at least high end DH bikes in the coming 2-5 years.

If this is the case, will all of the different rear suspension designs, FSR, VPP, dw-link, ect. become displaced by the single swingarm?

Am I right in thinking that any advantage of these advanced rear suspension links will be canceled out by a central gearbox where you want no chain-line growth?

Maybe, maybe not. There is a lot more to putting a gearbox in a bike than just making the gearbox. Either way, I think that many of the linkage suspension systems used in bicycles today will be gone in a few years time either way, or radically revamped. dw-link is most likely the exception. dw-link was designed as a suspension platform for all vehicles, from shaft driven motorcycles to chain driven bikes. Its a lot more in-depth than anyone has an idea of, and honestly, a huge technological leap on several levels from any "bike suspension" of the past when the reality of what the suspensions ACTUALLY do are compared. dw-link does things that are downright impossible to do with a single pivot suspension, and that have been falsely claimed to be done by all kinds of suspensions of the past and present. In my experience marketing BS can only last so long really, but physics is pretty much timeless so I am really excited to help usher in the future.

I remember about 8 months ago talking about the "derailleur in a box" that the Honda bike was reported to be. Glad to see my sources were indeed 100% on.

dw

 

[HRDTLBRO]

Dammit!
I knew I should have stolen Ska's at Mayhem. I'll be at the U.S. Open next year, if you guys just happen to uh...have a Sunday laying around. I'll even let you ride my new Iron Hor...oh, wait, ah sh**.