Light Bicycle Wheels
#1201
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#1202
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LOL.. I think we actually agree.. it is low, for any maker of a rim (of any construction), supposedly OK for road use pressures, for a 28mm tire.
#1203
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This is incorrect - even some of the hookless Enve rims have max pressure at 80psi. My wide, hookless Zipps have a max of 72.5 psi but they're careful to say that that's a max recommended, not a max for the stability of the rim.
Last edited by WhyFi; 08-25-20 at 06:01 PM.
#1204
I wouldn't worry about it much, unless the OP is planning on using tires under 30mm wide. I'm about the same weight as the OP, and with 30mm tires(on 23mm internal width hoops) 60/55psi works well.
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#1205
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If a manufacturer specs 60psi max for their hooked rims or 50psi for their hookless, I'm not going to touch them - I think that it says something about their confidence in their manufacturing and/or research. There are more options out there.
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#1206
Their 21mm and 23mm hoops are rated to 115psi. I doubt that their 25mm hoops are significantly different in construction.
#1207
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I’m on the cusp of purchasing a set of these wheels... after speaking with a customer service rep, they thought the AR56-30mm would not fit my 2019 Trek Emonda SL5 due to the rim width.
Does anyone have experience with this? My plan is to put the 28c Conti GP 5000s I have on the stock rims onto the LB rims.
If the 30mm wide rims won’t fit, what about 28mm? LB said they have RR56C03s which are 56mm deep and 28mm wide (21.6mm internal width).
Also hoping to get second opinions on Novatec/Bitex hubs... there was a positive comment on here about the Bitex, but are the DT Swiss 350 a significant upgrade from these two cheaper options?
Also hoping for feedback on the Sapim CX Rat spokes vs the Pillars... for heavy use training wheels, are the Sapims sturdier?
Does anyone have experience with this? My plan is to put the 28c Conti GP 5000s I have on the stock rims onto the LB rims.
If the 30mm wide rims won’t fit, what about 28mm? LB said they have RR56C03s which are 56mm deep and 28mm wide (21.6mm internal width).
Also hoping to get second opinions on Novatec/Bitex hubs... there was a positive comment on here about the Bitex, but are the DT Swiss 350 a significant upgrade from these two cheaper options?
Also hoping for feedback on the Sapim CX Rat spokes vs the Pillars... for heavy use training wheels, are the Sapims sturdier?
#1208
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"The WR65 can hold 75psi without a problem, I just confirmed with our engineer. But we might lower the tire pressure recommend numbers when it released online to avoid some extreme riders who run with the highest pressure without even consider their actual riding conditions."
I have asked him if the same holds true for the WR45 as well. Still, it would make me feel happier if they felt confident about the ratings. As WhyFi i said, why take the chance?
And to clarify - I dont plan to be riding 28mm WAM on these tires - looking at 32-33WAM. I brought up the 28mm WAM (which i have on my Rovals) to show that the Silca tire pressure calculator matched what seems to work well for me. So that gives me faith in the Silca recommendation to run 32mm WAM tires in the 65-70psi range.
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#1211
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Have you guys noticed that other than the AR56, most other rims on the LB page are now rated to a max of 60psi for hooked/50psi for tubeless?
That seems absurdly low to me. For a tire with a 28mm WAM, my optimal pressure is in the 80f/85r range for good tarmac - and that kinda dovetails with what Silca's tire pressure calculator says (which, in turn, is based on their extensive reach on total rolling efficiency, ie combining RR and vibration losses). Similarly, for a 32mm WAM tire, my optimal pressure is in the 65-70psi range. All tubeless, FWIW.
They said this was due to a tire blowing off the rim. What wasnt very clear was the circumstances which led to this -was it too narrow a tire (eg, 23 or 25mm mounted on a 25mm ID rim) or something else.
Leaving aside the argument of whether I SHOULD be riding at 65-70psi with 32mms, what do you guys think? LB is being absurdly conservative or would you not take the chance?
That seems absurdly low to me. For a tire with a 28mm WAM, my optimal pressure is in the 80f/85r range for good tarmac - and that kinda dovetails with what Silca's tire pressure calculator says (which, in turn, is based on their extensive reach on total rolling efficiency, ie combining RR and vibration losses). Similarly, for a 32mm WAM tire, my optimal pressure is in the 65-70psi range. All tubeless, FWIW.
They said this was due to a tire blowing off the rim. What wasnt very clear was the circumstances which led to this -was it too narrow a tire (eg, 23 or 25mm mounted on a 25mm ID rim) or something else.
Leaving aside the argument of whether I SHOULD be riding at 65-70psi with 32mms, what do you guys think? LB is being absurdly conservative or would you not take the chance?
I think so too. The same AR rims are rated to 115psi in the rim brake version - and except for 2 variations, all the disc brake options are now 60psi. Speaking to Charlie @ LB, he said:
"The WR65 can hold 75psi without a problem, I just confirmed with our engineer. But we might lower the tire pressure recommend numbers when it released online to avoid some extreme riders who run with the highest pressure without even consider their actual riding conditions."
"The WR65 can hold 75psi without a problem, I just confirmed with our engineer. But we might lower the tire pressure recommend numbers when it released online to avoid some extreme riders who run with the highest pressure without even consider their actual riding conditions."
Eg. For their WR45 rim, 50psi would be more than enough (actually way too high) if running a 50mm tire (max width that rim specs indicate is OK)
#1212
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Was the 75psi guidance in reference to your specific WAM of 32mm? Or for the smallest tire this rim is rated for, which is a 28mm (which might coincidentally end up being 32mm WAM?). Again, in general, it's odd that they provide a max PSI on their rims' spec pages, but not labeling these against a specific width tire. Did they reduce their PSI ratings because they DON'T distinguish recommended PSI by tire width?
Eg. For their WR45 rim, 50psi would be more than enough (actually way too high) if running a 50mm tire (max width that rim specs indicate is OK)
Eg. For their WR45 rim, 50psi would be more than enough (actually way too high) if running a 50mm tire (max width that rim specs indicate is OK)
And yes, you are right- their max PSI ratings dont take into account tire width. I assume it would be based on the least-wide tire that they recommend fitting on the rims (eg, 25c for AR rims, 28c for the WR rims).
#1213
The Silca pressure recommendations are based on tire size alone- so presumably WAM. For a 32mm WAM, it recommends a range from 60-68.5, depending on the quality of tarmac - so i am pretty much planning a hair under 65 for the front and a hair over 65 for the rear. A 75psi max rating would give me some additional headroom, that's all.
And yes, you are right- their max PSI ratings dont take into account tire width. I assume it would be based on the least-wide tire that they recommend fitting on the rims (eg, 25c for AR rims, 28c for the WR rims).
And yes, you are right- their max PSI ratings dont take into account tire width. I assume it would be based on the least-wide tire that they recommend fitting on the rims (eg, 25c for AR rims, 28c for the WR rims).
https://axs.sram.com/tirepressureguide
#1214
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Try this inflation calculator, and see if you get the same results.
https://axs.sram.com/tirepressureguide
https://axs.sram.com/tirepressureguide
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#1215
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Yeah, but why? It's not for no reason. Until that's answered, you're assuming unknown risk if you need/want to run at (still quite reasonable) pressures higher than their stated max.
You quite often tell people to toss relatively new tires if a cut brings up any question of safety - it's just a tire, it's not worth the potential hospitalization, just buy a new one. While a current LB owner will probably see this revision to very low max pressures differently, based upon their own experience, for a prospective buyer, this is a perfectly legitimate reason to cull one of these wheelsets from consideration - it's just a wheelset, there are more out there, it's not worth the potential hospitalization, just buy a different one.
Quite frankly, I was very hot on an LB wheelset for some time and I was very interested in hookless, but the lack of documentation, compatibility, etc etc gave me pause (along with the lead times - I'm impatient like that). Seeing this now makes me feel like I made the right move in spending a little bit more for something with better support (documentation and service) and availability. Yeah, I know - YMMV.
You quite often tell people to toss relatively new tires if a cut brings up any question of safety - it's just a tire, it's not worth the potential hospitalization, just buy a new one. While a current LB owner will probably see this revision to very low max pressures differently, based upon their own experience, for a prospective buyer, this is a perfectly legitimate reason to cull one of these wheelsets from consideration - it's just a wheelset, there are more out there, it's not worth the potential hospitalization, just buy a different one.
Quite frankly, I was very hot on an LB wheelset for some time and I was very interested in hookless, but the lack of documentation, compatibility, etc etc gave me pause (along with the lead times - I'm impatient like that). Seeing this now makes me feel like I made the right move in spending a little bit more for something with better support (documentation and service) and availability. Yeah, I know - YMMV.
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#1216
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The R45 disc rims which I have are rated for 130 psi max with 25c tires on the site, tubeless compatible (but I run them with latex inner tubes). The wider AR46 list 115 hooked and 70 hookless, with 25c tires.
It seems their new generation "pro" rims list 60 psi max without tire size, which is all sorts of weird.
It seems their new generation "pro" rims list 60 psi max without tire size, which is all sorts of weird.
Last edited by Branko D; 08-26-20 at 10:39 AM.
#1217
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Try this inflation calculator, and see if you get the same results.
https://axs.sram.com/tirepressureguide
https://axs.sram.com/tirepressureguide
Funnily enough, I set my initial tire pressure using a format posted by Psimet way back when, which left me with 100f/110r for 23c tires. I dropped 10psi for every next size - so 90/100 for 25 and 80/90 for 28s and that worked reasonably well (and also is kinda in the same ballpark as what SRAM, Enve, Silca say).
So for a 32WAM tire, 65-70 seems like a reasonable range.
#1218
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The R45 disc rims which I have are rated for 130 psi max with 25c tires on the site, tubeless compatible (but I run them with latex inner tubes). The wider AR46 list 115 hooked and 70 hookless, with 25c tires.
It seems their new generation "pro" rims list 60 psi max without tire size, which is all sorts of weird.
It seems their new generation "pro" rims list 60 psi max without tire size, which is all sorts of weird.
You quite often tell people to toss relatively new tires if a cut brings up any question of safety - it's just a tire, it's not worth the, potential hospitalization, just buy a new one. While a current LB owner will probably see this revision to very low max pressures differently, based upon their own experience, for a prospective buyer, this is a perfectly legitimate reason to cull one of these wheelsets from consideration - it's just a wheelset, there are more out there, it's not worth the potential hospitalization, just buy a different one.
For me, I'd be ok if they said: "the rim has the strength to withstand the pressure. It is just that we had an issue with someone running XX brand tire of width YY, and for that reason, we recommend a lower pressure just to be conservative". If I had the info, I could do my own risk assessment of whether I wanted to try it or not. But they are being very cagey with their answers, just saying "we are being conservative because we cannot know your riding conditions". Maybe it is a language/cultural thing.... either way, the lack of specific info is putting me off. Especially when different rims in the same dimensions have different ratings.
Last edited by guadzilla; 08-26-20 at 10:55 AM.
#1219
I think guadzilla is looking at the wrong hoops for his needs, and I can't understand why he wants to run such a high pressure. I thought he was about 185#
Last edited by noodle soup; 08-26-20 at 10:54 AM.
#1220
#1221
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For me, I'd be ok if they said: "the rim has the strength to withstand the pressure. It is just that we had an issue with someone running XX brand tire of width YY, and for that reason, we recommend a lower pressure just to be conservative". If I had the info, I could do my own risk assessment of whether I wanted to try it or not. But they are being very cagey with their answers, just saying "we are being conservative because we cannot know your riding conditions". Maybe it is a language/cultural thing.... either way, the lack of specific info is putting me off. Especially when different rims in the same dimensions have different ratings.
#1222
https://www.lightbicycle.com/U-shape...ompatible.html
#1223
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looking at their narrow 29er hoops I found this "Tyre Pressure 20-40psi recommended". It looks like they are recommending ideal tire pressure, not the maximum tire pressure the hoops can withstand.
https://www.lightbicycle.com/U-shape...ompatible.html
https://www.lightbicycle.com/U-shape...ompatible.html
#1224
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The Silca pressure recommendations are based on tire size alone- so presumably WAM. For a 32mm WAM, it recommends a range from 60-68.5, depending on the quality of tarmac - so i am pretty much planning a hair under 65 for the front and a hair over 65 for the rear. A 75psi max rating would give me some additional headroom, that's all.
And yes, you are right- their max PSI ratings dont take into account tire width. I assume it would be based on the least-wide tire that they recommend fitting on the rims (eg, 25c for AR rims, 28c for the WR rims).
And yes, you are right- their max PSI ratings dont take into account tire width. I assume it would be based on the least-wide tire that they recommend fitting on the rims (eg, 25c for AR rims, 28c for the WR rims).
BTW.. not sure you've said.. which rim(s) are you specifically interested in, for what type of riding (road/surface)?
#1225
After reading some emails from them, you might feel differently. It's clear that English isn't their first language.