And then next thing you know there’ll be position sensitive damping and I’ll be sitting here wondering why so much complexity has been added all to...
And then next thing you know there’ll be position sensitive damping and I’ll be sitting here wondering why so much complexity has been added all to solve something easily doable with a linkage.
Springs in series result in a crazy low initial spring rate unless you’ve got at least one very stiff spring in there. Half of what they help with in off road applications doesn’t apply to bikes at all. In theory it does let you pick an initial sprint rate, final spring rate, and transition point, but without winding your own springs the customization available is surprisingly limited.
Completely random and off topic, but I was wondering if youre able to share how the StumpJumper Evo rear triangles did on sales and reviews? Innovation as a whole is slowing down. But the idea of making a bike into a different beast via your setup is wicked cool. Are there other bikes in the pipeline that interest you to do that again?
just saw this in mojo suspension story. Looks like some kind of dual spring setup for fine tuning/recreating individual dual rate spring curve. I think Dave...
just saw this in mojo suspension story. Looks like some kind of dual spring setup for fine tuning/recreating individual dual rate spring curve. I think Dave Garland did something like this for the boxxer quite some years ago.
You definitely need that dual spring rate for a super shitty frame like that TR 11.
Looks like Pinkerton is on the ghetto tubeless wagon (from USDH pit bits). I remember seeing another WC rider with a similar setup some years ago but I forgot who it was.
Looks like Pinkerton is on the ghetto tubeless wagon (from USDH pit bits). I remember seeing another WC rider with a similar setup some years ago...
Looks like Pinkerton is on the ghetto tubeless wagon (from USDH pit bits). I remember seeing another WC rider with a similar setup some years ago but I forgot who it was.
Looks like Pinkerton is on the ghetto tubeless wagon (from USDH pit bits). I remember seeing another WC rider with a similar setup some years ago...
Looks like Pinkerton is on the ghetto tubeless wagon (from USDH pit bits). I remember seeing another WC rider with a similar setup some years ago but I forgot who it was.
I've often asked the same question when conventional CVTs are used in place of traditional automatic gearboxes in cars, and then programmed to pretend to be...
I've often asked the same question when conventional CVTs are used in place of traditional automatic gearboxes in cars, and then programmed to pretend to be an automatic gearbox...
However one good reason I can think of is that eCVTs are far simpler than gearboxes so they can be smaller, lighter and more durable all at the same time.
The CVTs in my Subaru and Toyota are paired with a conventional automatic transmission - they just smooth out the transition between gears when you aren't...
The CVTs in my Subaru and Toyota are paired with a conventional automatic transmission - they just smooth out the transition between gears when you aren't being aggressive. Easy enough to see the gear change by watching the tach. I assumed most/all car CVTs are like this, but maybe I'm wrong.
If the internet isn't wrong, some modern hybrids use planetary gear eCVTs which do not require a conventional gear system, using the ICE on one side, and electric on the other. I haven't done research to find cars that actually do this though, so maybe not yet.
In the absence of a conventional transmission, the "feel" of a gear change would need to be programmed. I'm not sure what I would opt for. I do like to modify my cadence at different times, so I could imagine that rather than manually changing gears, I would opt for some approach to let me spin fast sometimes, and mash at other points. Kind of a moot point though when even mashing I couldn't match 50% of the 2HP motor power for more than a few seconds.
Looks like Pinkerton is on the ghetto tubeless wagon (from USDH pit bits). I remember seeing another WC rider with a similar setup some years ago...
Looks like Pinkerton is on the ghetto tubeless wagon (from USDH pit bits). I remember seeing another WC rider with a similar setup some years ago but I forgot who it was.
Marshy set up Minaar's wheels like that for Ft. Bill (maybe?) a few years ago...
Looks like Pinkerton is on the ghetto tubeless wagon (from USDH pit bits). I remember seeing another WC rider with a similar setup some years ago...
Looks like Pinkerton is on the ghetto tubeless wagon (from USDH pit bits). I remember seeing another WC rider with a similar setup some years ago but I forgot who it was.
Yeah, I posted this a page or two ago. Dual motor eCVTs were a new discovery for me. Absolutely makes sense for ebikes, but no chance...
Yeah, I posted this a page or two ago. Dual motor eCVTs were a new discovery for me. Absolutely makes sense for ebikes, but no chance at all of "trickle-down" technology to pedal bikes, as a few folks in the thread had hoped for.
The pink ones posted about Gates having a different opinion apparently.
Name goes back some 15-20 years ago when first proper tubeless components were introduced (tubeless ready tires, tubeless wheelsets like mavic demax, which are not drilled throught etc) but a lot of us scrubs couldnt afford those and sealants were not as good as they are today so if not using proper parts the setup most likely wouldnt hold air and a ghetto setup was invented by cutting a 20" innertube and streching it over a rim and then mounting a tire, so the cut innertube would rest between the tire and the rim effectively sealing it. Combined with the sealant the two would just bond together so it was absolute nighmare to get off (thats why it works so good agains burping). I've actually built my first ghetto tubless few weeks ago after an decade (old 27.5 dh bike with cheap rear rim wouldnt hold air), was a fun trip down the memory lane and the thing really works everytime, but it takes a long time to setup and you have to destroy an innertube for it.
Edit, had to take a picture and share it with friends as it has been so long:
If pinky is running ghetto tubeless, maybe trying to prevent burping and doesn't want an insert?
If he’s a rim destroyer, dealing with inserts on your own as a racer that’s now used to a mechanic, is probably really annoying. I know that my dh bike needs a rear rim but there’s a Cush Core in there so I’m going to wait it out…
I've rarely had problems with inserts. As long as you use proper technique. Last shop that I worked at, other mechanics would bring me Cushcores to install for them.
Name goes back some 15-20 years ago when first proper tubeless components were introduced (tubeless ready tires, tubeless wheelsets like mavic demax, which are not drilled...
Name goes back some 15-20 years ago when first proper tubeless components were introduced (tubeless ready tires, tubeless wheelsets like mavic demax, which are not drilled throught etc) but a lot of us scrubs couldnt afford those and sealants were not as good as they are today so if not using proper parts the setup most likely wouldnt hold air and a ghetto setup was invented by cutting a 20" innertube and streching it over a rim and then mounting a tire, so the cut innertube would rest between the tire and the rim effectively sealing it. Combined with the sealant the two would just bond together so it was absolute nighmare to get off (thats why it works so good agains burping). I've actually built my first ghetto tubless few weeks ago after an decade (old 27.5 dh bike with cheap rear rim wouldnt hold air), was a fun trip down the memory lane and the thing really works everytime, but it takes a long time to setup and you have to destroy an innertube for it.
Edit, had to take a picture and share it with friends as it has been so long:
Props for the trip down memory lane. I have fond memories of ghetto tubeless'ing many a wheel back around 2004 or a bit later. Stan's rubber strips were a thing back then but retailed for $50, or $25 (cad) cost. It was much cheaper to use a 20" tube, but also more effective with the extra sealing at the bead. It also meant we could run better rim options at the time that weren't tubeless compatible. Mavic 729s were the rims back then, and wouldn't hold a tubeless seal unless you went ghetto.
Could the issue with 729s be the width and the effectively narrow tires of the old days? In early 2010s I ran Mavic 721s and High Rollers (II) tubeless with duct tape sealing the holes in the rim bed without a problem.
Yeah, I posted this a page or two ago. Dual motor eCVTs were a new discovery for me. Absolutely makes sense for ebikes, but no chance...
Yeah, I posted this a page or two ago. Dual motor eCVTs were a new discovery for me. Absolutely makes sense for ebikes, but no chance at all of "trickle-down" technology to pedal bikes, as a few folks in the thread had hoped for.
The pink ones posted about Gates having a different opinion apparently.
About an eCVT, or about a belt CVT? Gates makes belts, and I think there was a patent reveal a while back for a belt CVT for pedal bikes. eCVTs require 2-power sources to operate - either 2 motors or an ICE paired with a motor in the case of hybrid vehicles. Unclear where the second power source would come from on pedal bikes. Maybe a really crazy tandem bike design, where the two riders have to pedal at different cadences in order to get the gearing they want. Sounds like something Sam Pilgrim would ride.
I think power losses on belt CVTs is something like an order greater than a chain and/or conventional gearboxes. I'm not optimistic that belt-CVTs on pedal bikes will make it to production.
Could the issue with 729s be the width and the effectively narrow tires of the old days? In early 2010s I ran Mavic 721s and High...
Could the issue with 729s be the width and the effectively narrow tires of the old days? In early 2010s I ran Mavic 721s and High Rollers (II) tubeless with duct tape sealing the holes in the rim bed without a problem.
I think tire beads and rim beads were just designed differently back then. A 26x2.5 DHF or DHR was wide enough, but the Maxxis bead lacked meat to seal up. I also ran 721s on my trail bikes back then.
Its a shame UST never really took off. Sealant-less and tapeless rims would have solved a lot of the last decade's tyre related problems for me and many friends.
Name goes back some 15-20 years ago when first proper tubeless components were introduced (tubeless ready tires, tubeless wheelsets like mavic demax, which are not drilled...
Name goes back some 15-20 years ago when first proper tubeless components were introduced (tubeless ready tires, tubeless wheelsets like mavic demax, which are not drilled throught etc) but a lot of us scrubs couldnt afford those and sealants were not as good as they are today so if not using proper parts the setup most likely wouldnt hold air and a ghetto setup was invented by cutting a 20" innertube and streching it over a rim and then mounting a tire, so the cut innertube would rest between the tire and the rim effectively sealing it. Combined with the sealant the two would just bond together so it was absolute nighmare to get off (thats why it works so good agains burping). I've actually built my first ghetto tubless few weeks ago after an decade (old 27.5 dh bike with cheap rear rim wouldnt hold air), was a fun trip down the memory lane and the thing really works everytime, but it takes a long time to setup and you have to destroy an innertube for it.
Edit, had to take a picture and share it with friends as it has been so long:
dear god this looks worse than trying to fit a cushcore under a dh kryptotal
I think Marshy's trick was to use roofing sealant between the rim and the tire.
Per PB La Thuile tech randoms of this year, they still do it at Mondraker (can Vital detectives identify who's mechanic that is just by the hand and legs ? 😄 )
Not to put too fine a point on it, but a 4mm increase in a 57mm width, is not lost in the noise. It will be...
Not to put too fine a point on it, but a 4mm increase in a 57mm width, is not lost in the noise. It will be a measurably stiffer wheel (if that's what you want). Of course both options beat the crazy drive-side dish on typical 148 12-speed wheels.
I should have specified that building between the Hope hub and the Oneup hub the 4mm would be lost in the noise. There are other factors at play with wheel systems one of which is the PCD, which hope has the leg up on with a larger PCD resulting in shorter spokes, which helps with the bracing angle and in general, shorter spokes = stiffer wheel. If you run the numbers between the oneup hub and the pro5 you gain 10% in lateral stiffness with less radial and torsional stiffness, ~3%. Overall wheel strength when looking at the combined metrics of lateral, radial and torsional stiffness, you are gaining maybe 5% in overall strength.
If you can feel that in your wheels, bravo, I most definitely can't and I bet very few people could. It's equivalent to going from a 1.8 to a 1.75mm spoke.
FWIW Dr Mathew Ford wrote a very comprehensive paper for his Ph.d thesis on the mechanics and optimization of the bicycle wheel.
Per PB La Thuile tech randoms of this year, they still do it at Mondraker (can Vital detectives identify who's mechanic that is just by the...
Per PB La Thuile tech randoms of this year, they still do it at Mondraker (can Vital detectives identify who's mechanic that is just by the hand and legs ? 😄 )
Not to put too fine a point on it, but a 4mm increase in a 57mm width, is not lost in the noise. It will be...
Not to put too fine a point on it, but a 4mm increase in a 57mm width, is not lost in the noise. It will be a measurably stiffer wheel (if that's what you want). Of course both options beat the crazy drive-side dish on typical 148 12-speed wheels.
I should have specified that building between the Hope hub and the Oneup hub the 4mm would be lost in the noise. There are other factors...
I should have specified that building between the Hope hub and the Oneup hub the 4mm would be lost in the noise. There are other factors at play with wheel systems one of which is the PCD, which hope has the leg up on with a larger PCD resulting in shorter spokes, which helps with the bracing angle and in general, shorter spokes = stiffer wheel. If you run the numbers between the oneup hub and the pro5 you gain 10% in lateral stiffness with less radial and torsional stiffness, ~3%. Overall wheel strength when looking at the combined metrics of lateral, radial and torsional stiffness, you are gaining maybe 5% in overall strength.
If you can feel that in your wheels, bravo, I most definitely can't and I bet very few people could. It's equivalent to going from a 1.8 to a 1.75mm spoke.
FWIW Dr Mathew Ford wrote a very comprehensive paper for his Ph.d thesis on the mechanics and optimization of the bicycle wheel.
You need a lot of PCD to offset the 4 mm lateral difference and have the spoke angle the same over the two variants.
Also, FWIW, I prefer my wheelsets to have the same length of spokes if at all possible or at least as many as possible. Without having the left and right offsets the same, you get a double whammy that way as the PCD on the NDS has to be larger to be able to have the same spokes on both sides.
Completely random and off topic, but I was wondering if youre able to share how the StumpJumper Evo rear triangles did on sales and reviews? Innovation as a whole is slowing down. But the idea of making a bike into a different beast via your setup is wicked cool. Are there other bikes in the pipeline that interest you to do that again?
You definitely need that dual spring rate for a super shitty frame like that TR 11.
Looks like Pinkerton is on the ghetto tubeless wagon (from USDH pit bits). I remember seeing another WC rider with a similar setup some years ago but I forgot who it was.
What's ghetto about it?
I’m assuming this is the “1/2 of a tube glued to a tire” tubeless setup
Looks like it. It's heavy but works great against burping and if you dent the rim.
Shoot - years of watching the tach move, but never actually doing even the most basic research. Their "programmed" gears fooled me.
Marshy set up Minaar's wheels like that for Ft. Bill (maybe?) a few years ago...
Can you legit tell that it’s a tube not just a generous amount of glue?
The pink ones posted about Gates having a different opinion apparently.
Yes.
I don't know, if there was regular product doing the same thing (stans rim strip), can it be still called ghetto?
Name goes back some 15-20 years ago when first proper tubeless components were introduced (tubeless ready tires, tubeless wheelsets like mavic demax, which are not drilled throught etc) but a lot of us scrubs couldnt afford those and sealants were not as good as they are today so if not using proper parts the setup most likely wouldnt hold air and a ghetto setup was invented by cutting a 20" innertube and streching it over a rim and then mounting a tire, so the cut innertube would rest between the tire and the rim effectively sealing it. Combined with the sealant the two would just bond together so it was absolute nighmare to get off (thats why it works so good agains burping). I've actually built my first ghetto tubless few weeks ago after an decade (old 27.5 dh bike with cheap rear rim wouldnt hold air), was a fun trip down the memory lane and the thing really works everytime, but it takes a long time to setup and you have to destroy an innertube for it.
Edit, had to take a picture and share it with friends as it has been so long:
They were a nightmare to setup, but for sure they allowed tyres and soft mavic rims of theat period to last waaaayyy longer than even proper tubeless.
I have cut the tyre off the rim a few times as I found it easier than removing it from ghetto tubeless setup!
If pinky is running ghetto tubeless, maybe trying to prevent burping and doesn't want an insert?
If he’s a rim destroyer, dealing with inserts on your own as a racer that’s now used to a mechanic, is probably really annoying. I know that my dh bike needs a rear rim but there’s a Cush Core in there so I’m going to wait it out…
I've rarely had problems with inserts. As long as you use proper technique. Last shop that I worked at, other mechanics would bring me Cushcores to install for them.
Props for the trip down memory lane. I have fond memories of ghetto tubeless'ing many a wheel back around 2004 or a bit later. Stan's rubber strips were a thing back then but retailed for $50, or $25 (cad) cost. It was much cheaper to use a 20" tube, but also more effective with the extra sealing at the bead. It also meant we could run better rim options at the time that weren't tubeless compatible. Mavic 729s were the rims back then, and wouldn't hold a tubeless seal unless you went ghetto.
Could the issue with 729s be the width and the effectively narrow tires of the old days? In early 2010s I ran Mavic 721s and High Rollers (II) tubeless with duct tape sealing the holes in the rim bed without a problem.
About an eCVT, or about a belt CVT? Gates makes belts, and I think there was a patent reveal a while back for a belt CVT for pedal bikes. eCVTs require 2-power sources to operate - either 2 motors or an ICE paired with a motor in the case of hybrid vehicles. Unclear where the second power source would come from on pedal bikes. Maybe a really crazy tandem bike design, where the two riders have to pedal at different cadences in order to get the gearing they want. Sounds like something Sam Pilgrim would ride.
I think power losses on belt CVTs is something like an order greater than a chain and/or conventional gearboxes. I'm not optimistic that belt-CVTs on pedal bikes will make it to production.
I think tire beads and rim beads were just designed differently back then. A 26x2.5 DHF or DHR was wide enough, but the Maxxis bead lacked meat to seal up. I also ran 721s on my trail bikes back then.
Things are looking Blur-ry
Its a shame UST never really took off. Sealant-less and tapeless rims would have solved a lot of the last decade's tyre related problems for me and many friends.
https://www.vitalmtb.com/community/rog/campmajo-myotragus-dh#comment-829356
Thoughts on really high pivot bikes? Wouldn't this design run into that dumb itrack patent?
dear god this looks worse than trying to fit a cushcore under a dh kryptotal
I think Marshy's trick was to use roofing sealant between the rim and the tire.
Per PB La Thuile tech randoms of this year, they still do it at Mondraker (can Vital detectives identify who's mechanic that is just by the hand and legs ? 😄 )
I should have specified that building between the Hope hub and the Oneup hub the 4mm would be lost in the noise. There are other factors at play with wheel systems one of which is the PCD, which hope has the leg up on with a larger PCD resulting in shorter spokes, which helps with the bracing angle and in general, shorter spokes = stiffer wheel. If you run the numbers between the oneup hub and the pro5 you gain 10% in lateral stiffness with less radial and torsional stiffness, ~3%. Overall wheel strength when looking at the combined metrics of lateral, radial and torsional stiffness, you are gaining maybe 5% in overall strength.
If you can feel that in your wheels, bravo, I most definitely can't and I bet very few people could. It's equivalent to going from a 1.8 to a 1.75mm spoke.
FWIW Dr Mathew Ford wrote a very comprehensive paper for his Ph.d thesis on the mechanics and optimization of the bicycle wheel.
Flashback to #freckleGate....
You need a lot of PCD to offset the 4 mm lateral difference and have the spoke angle the same over the two variants.
Also, FWIW, I prefer my wheelsets to have the same length of spokes if at all possible or at least as many as possible. Without having the left and right offsets the same, you get a double whammy that way as the PCD on the NDS has to be larger to be able to have the same spokes on both sides.
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