Wheels, Tires, Tubes, Tubeless, Tubs, Spokes, Hookless, Hubs, and more!
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If a new wheel tech is released, (say for example, TPU tubes, a brand new tire, or a new rim standard), feel free to start the discussion in the popular "Road". Your topic will eventually be moved here!
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AscentBikes
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by AscentBikes on Mon Oct 10, 2022 11:25 am
TobinHatesYou wrote: ↑Mon Oct 10, 2022 10:11 am
AscentBikes wrote: ↑Mon Oct 10, 2022 9:37 am
Hello Tobin,
Thank you for your feedback. I'm sorry that you encountered this wobble while riding. This is the first time I've heard of this happening. 50mph/80kph is actually pretty darn fast!
I've had riders do high speed descents so far without issues - they have mentioned that the Polaris wants to track straight, especially after a gust, but never with an oscillation. Are the oscillations self-damping (trending toward zero) or self-reinforcing (increasing in magnitude)? How long do they last, and are they slow (~1Hz) or medium (~10hz) or fast (>100hz)? It's curious that the oscillations only appear if you grip hard or not at all.
Couple of hypotheses:
1) There is an unexpected interaction with your fork. Best way to test would be repeating the descent with another bike. I recall you were with another rider on the Polaris as well, and he experienced no such issue.
2) Residual imbalance in wheel/tire/tube system is exciting the front wheel. Try performing a dynamic balance on the complete front wheel and repeating the descent.
3) Could the IsoSpeed damper be decreasing the frame stiffness sufficiently to lower the resonant frequency? If at all possible, try increasing the stiffness of the IsoSpeed damper and try again.
4) Check if headset is properly preloaded.
Yours is the first Madone with Polaris, so I remain committed to working on this with you.
As for 50-60mms.. let me launch my 42 first yeah
CFD, custom molds, and testing are expensive.
Regards
QX
The oscillation is self-damping and a low frequency, but faster than 1Hz. It happens with a medium grip and is less common when I have either a firm or loose grip.
My bike well maintained and doesn’t have a front IsoSpeed damper. I will probably mount my 7.8s and ride those on the same roads at some point to see if they exhibit the same wobbles.
I took that corner around 5mph faster than Peter did.
I haven’t ruled out imbalance in the wheels, but I feel like that would create different sensations…vertical bounce vs side-to-side wiggle.
Hello Tobin,
Alright, please let me know how that works out. It would be great if you could try another bike, maybe take Peter's for a ride.
I meant to stiffen up the rear IsoSpeed damper actually - I believe only Specialized has that Future Shock thingy.
Yeah, I hear you about the vertical bounce vs wiggle. It seems that it's an underdamped response to the steering input.
I'll follow up with you separately!
Regards
QX
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apr46
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by apr46 on Tue Oct 11, 2022 5:40 am
TobinHatesYou wrote: ↑Mon Oct 10, 2022 5:29 am
As in anything that might cause an abrupt steering force like a push from my hand or an uneven patch in the road will result in a fast wobble. I won't call it speed wobbles because it doesn't endure for more than 1-2 seconds and doesn't seem to be caused by a lack of stiffness. With my ENVEs, if the wheels get pushed in on direction, they keep steering in that direction. It feels like these wheels are so deep, there’s a rudder effect trying to push them back into a neutral position against the wind. When this happens, there is an over-correction and it points past neutral, then back-and-forth. This seems to happen when I have neither a firm grip on the bars, nor a loose grip. If I grip my bars more firmly or more loosely the oscillation dissipates (or is less likely to occur in the first place.)
I run the same tires (gp5000 s TR, 28mm) on my pair and have hit that kind fo speed a few times. I didn't notice the effect you are mentioning, but my senses were sufficiently overwhelmed by going that speed. I dont even recall how hard i gripped the bars during those descents.
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TobinHatesYou
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by TobinHatesYou on Tue Oct 11, 2022 6:45 am
apr46 wrote: ↑Tue Oct 11, 2022 5:40 am
I run the same tires (gp5000 s TR, 28mm) on my pair and have hit that kind fo speed a few times. I didn't notice the effect you are mentioning, but my senses were sufficiently overwhelmed by going that speed. I dont even recall how hard i gripped the bars during those descents.
I hit those speeds regularly, but since I’m the only one who seems to be experiencing this, more testing on my part is needed. I’ll probably chuck my 7.8s on since they’re even deeper than the Polaris and do the same descent sometime, but it’s a low priority right now.
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AscentBikes
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by AscentBikes on Tue Oct 11, 2022 6:55 am
TobinHatesYou wrote: ↑Tue Oct 11, 2022 6:45 am
apr46 wrote: ↑Tue Oct 11, 2022 5:40 am
I run the same tires (gp5000 s TR, 28mm) on my pair and have hit that kind fo speed a few times. I didn't notice the effect you are mentioning, but my senses were sufficiently overwhelmed by going that speed. I dont even recall how hard i gripped the bars during those descents.
I hit those speeds regularly, but since I’m the only one who seems to be experiencing this, more testing on my part is needed. I’ll probably chuck my 7.8s on since they’re even deeper than the Polaris and do the same descent sometime, but it’s a low priority right now.
Curious, how much weight do you have on the handlebars? Like do you sit more forward or backward?
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TobinHatesYou
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by TobinHatesYou on Tue Oct 11, 2022 8:01 am
AscentBikes wrote: ↑Tue Oct 11, 2022 6:55 am
Curious, how much weight do you have on the handlebars? Like do you sit more forward or backward?
I have a long torso and an aggressive position so a lot of weight forward of the BB, but most of it is held up by my core.
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Mr.Gib
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by Mr.Gib on Tue Oct 11, 2022 6:40 pm
TobinHatesYou wrote: ↑Mon Oct 10, 2022 5:29 am
at high speeds my Polaris front wheel will wobble/oscillate if “provoked.”
Stepping back to look at the big picture, it is most likely that there is nothing wrong with the wheel or the bike. These situations so often seem to be the result of interaction between system components. It just might be that that front wheel and fork do not "get along" at 80 km/h. Sounds like some interplay between them is creating an occilating disruption of air flow, pressure, etc. It's nice that it is self dampening, but I'd be super paranoid that slightly different conditions, higher speed, more wind, wrong surface, could cause it to get out of control. You are doing a lot of super intense riding. In your situation I would not tolerate anything that does not inspire 100% confidence. I'd put that front wheel aside. Perhaps Ascent will send you a matching shallower front wheel when ready.
wheelsONfire wrote: When we ride disc brakes the whole deal of braking is just like a leaving a fart. It happens and then it's over. Nothing planned and nothing to get nervous for.
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AscentBikes
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by AscentBikes on Wed Oct 12, 2022 4:20 pm
Tobin,
If you wish to test out the 42mm, let me know.
My intent for Polaris is to give the rider confidence - if there's anything holding you back, I'd like to try and solve it with you.
As for everyone else, here's a little teaser
Stay tuned for our official launch on 15 October, 12pm Singapore Time (GMT +8)
QX
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AscentBikes
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by AscentBikes on Fri Oct 14, 2022 12:59 am
Aesch wrote: ↑Thu Oct 13, 2022 7:13 pm
@ QX, will you sell rims only and in 28h version? Thanks!
Aesch, yes we sell rims only. If you're interested, just drop us a message at
contact@ascent-bikes.com please. Unfortunately, only in 24H. Our carbon fiber placement is optimized at the holes, so we can't just drill 28H - we'd need to redo the entire carbon layup for that.
Regards
QX
Polaris 69
Standard: S$800 each
Raw: S$950 each
ERD: 507mm
Holes: 24H
Polaris 42:
Standard: S$700 each
Raw: S$850 each
ERD: 555mm
Holes: 24H
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BigBoyND
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by BigBoyND on Fri Oct 14, 2022 8:41 am
This might be a great option for those of us in the EU due to import duties.
Have you looked into offering the super light Tactic hub as an option? How would pricing compare to the DT180 version?
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AscentBikes
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by AscentBikes on Fri Oct 14, 2022 9:52 am
BigBoyND wrote: ↑Fri Oct 14, 2022 8:41 am
This might be a great option for those of us in the EU due to import duties.
Have you looked into offering the super light Tactic hub as an option? How would pricing compare to the DT180 version?
Very interesting - even with hub, spoke, and building costs, you're saying this is more cost-effective?
I'd be happy to offer the rims for purchase on the site as well.
I haven't explored Tactic Racing yet - they're really pricey at 1300 USD per hub. If you're chasing pure lightness, even the Extralites are half the price, and 3g lighter.
I'm open to the option though, if you guys are interested, I can try to start a conversation with them.
QX
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mrlobber
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by mrlobber on Fri Oct 14, 2022 9:55 am
BigBoyND wrote: ↑Fri Oct 14, 2022 8:41 am
This might be a great option for those of us in the EU due to import duties.
This is why I also purchased the rims only, so great to see that option offered.
Minimum bike categories required in the stable:
Aero bike | GC bike | GC rim bike | Climbing bike | Climbing rim bike | Classics bike | Gravel bike | TT bike | Indoors bike
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BigBoyND
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by BigBoyND on Fri Oct 14, 2022 10:15 am
AscentBikes wrote: ↑Fri Oct 14, 2022 9:52 am
BigBoyND wrote: ↑Fri Oct 14, 2022 8:41 am
This might be a great option for those of us in the EU due to import duties.
Have you looked into offering the super light Tactic hub as an option? How would pricing compare to the DT180 version?
Very interesting - even with hub, spoke, and building costs, you're saying this is more cost-effective?
I'd be happy to offer the rims for purchase on the site as well.
I haven't explored Tactic Racing yet - they're really pricey at 1300 USD per hub. If you're chasing pure lightness, even the Extralites are half the price, and 3g lighter.
I'm open to the option though, if you guys are interested, I can try to start a conversation with them.
QX
I'm not sure which comes out cheaper, but it's a good option to have for people living in high tax areas.
Yeah I see Tactic is $1300 vs $1100 for DT180. But since those are retail prices, maybe commercial pricing is better?
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AscentBikes
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by AscentBikes on Fri Oct 14, 2022 11:39 am
BigBoyND wrote: ↑Fri Oct 14, 2022 10:15 am
AscentBikes wrote: ↑Fri Oct 14, 2022 9:52 am
BigBoyND wrote: ↑Fri Oct 14, 2022 8:41 am
This might be a great option for those of us in the EU due to import duties.
Have you looked into offering the super light Tactic hub as an option? How would pricing compare to the DT180 version?
Very interesting - even with hub, spoke, and building costs, you're saying this is more cost-effective?
I'd be happy to offer the rims for purchase on the site as well.
I haven't explored Tactic Racing yet - they're really pricey at 1300 USD per hub. If you're chasing pure lightness, even the Extralites are half the price, and 3g lighter.
I'm open to the option though, if you guys are interested, I can try to start a conversation with them.
QX
I'm not sure which comes out cheaper, but it's a good option to have for people living in high tax areas.
Yeah I see Tactic is $1300 vs $1100 for DT180. But since those are retail prices, maybe commercial pricing is better?
I wish we had that kind of OEM relationship with DT!
As it is, pricing is pretty much retail - maybe a slight discount here and there, but in terms of deep discounts, nah man.
As it is, all our 42mm rims are currently built into wheelsets - when more come, I will make the option to purchase rims only available.
Cheers
QX