This thread has discussed a few different carbon rims and wheel builds. Just to be clear and for future reference can you list the make, brand, size and model of rim you used and any other wheel build details that may be useful?
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Edited above - and done so:
I did create a thread for this new LightBicycle rim but all content started to drift to this thread and now it is too fiddly to request it is moved over.
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Iāve not been able to ride this as Iām under hospital advice to avoid over exerting myself (possible retinal tear!)ā¦ but happily it has held 50PSI without issue and I would happily add more if I needed it.
Braus needed around 49PSI to feel stable for my 81kg - but I think this rim will feel just as stiff at 45PSI - tested to 50 as a max for me.
Very happy indeed 
(Just hope I could get back to riding soon)
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IIs it still those values after inflation and the adjustments you made afterwards?
Regarding the acronyms DS and NDS, Iāve just seen that they stand for Drive-Side and Non-Drive Side. Iām sure Iāve missed something, Iām basing this on the side of the disc.
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Yeah these terms really drive me mad -
But Iāve learned to stick to looking at drive and non-dive sides - remembering that non-drive is where the disc goes.
Yes 25 was for the short spokes on NDS - and 20 for DS.
25 seems to equal 120 kgf with 26 being more like 135 - which is the rimās upper limit. But that was before I inflated it.
I need to recheck numbers and tighten again - I suspect 1 perhaps 1.5 turns all the way around.
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So, I had to remove my NightRider tire today. A spoke snapped yesterday and the nipple went into the rim 
I have not found how to use the tool to remove the tire. I had to do it all by hand. No big deal, but I doubt the tool has ever been designed to remove a tire. Sorry about that!
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Iāve now put it back to 45ish PSI and then noted the spoke tensions had dropped around 2 full points on the scale.
A half turn on each spoke got them back to 20-22 DS, and 25-26 NDS -
This does mean should I take the tyre off tensions would be over spec. For this Iād either not worry as the wheel wonāt be ridden like that or drop the tensions all round before deflating.
I just gave it a test ride at 45PSI and it glides along but perhaps it isnāt as nimble a feeling as I got from the Braus. This could be due to the wider hub being heavier and errā¦ wider, and also due to my needing more PSI in the tyre for it to feel as firm as the Vee tyre I run on the Braus rim.
Just tested it at 50ish and the system is much firmer for me - so this will likely translate into a more directional feel.
No more time to test right now but the main takeaway here is that Iām happy running it at 50PSI - I could even test 55 without worrying - and I will one day try the King George Ultimate again to see how it behaves in this rim (didnāt like it in the Braus at 50PSI).
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Iād say either donāt care at all or drop it all round so that the tensions are within specs limits when the tire is deflated. Because fiddling with spokes just to change a tire or a tube doesnāt seem a welcome thing to do in my view. But most importantly, you can end up having a flat anytime (donāt even needs to happen when you ride the thing), which means the spoke tensions can end up being too high at any moment.
Just out of curiosity (since I tend to ride with not so high tire pressures): Is the effect of tire pressure on spoke tension equally pronounced with aluminium rims or is this a peculiarity of carbon rims?
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Itās something Iāve only heard of / seen with carbon rims. Perhaps it happens to a lesser extent on aluminium rims.
Iāve been told categorically that Iām imagining this issue - and that rimās spoke tension cannot be lessened due to tyre pressure - but the fact remains that they do. (So it seems some people out there donāt think this can physically happen!)
I know my pro wheel builder accounts for this when tensioning rims - so yeah it probably happens on all rims but carbon more so.
I think youāre right about just leaving it high. I very much doubt it will actually break the rim. I think the spec is for ridden rims - as the stresses on the spokes and nipples will be extreme then and this is when over tensioned spokes could be bad. But stationary, unweighted and with a tyre off - I highly doubt it is as issue.
Far greater issue would be to ride with loose spokes at 50PSI.
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Have you tried measuring the tensions right before inflating the tire ? And have you tried inflating, measuring and then deflating before re-measuring it ?
I cannot see how inflating the tire could cause the spokes to lose tension, but I can see the spokes losing tensions overtime.
Itās normal!
I found the same thing with the Braus carbon rim. When you inflate the tire, thereās a force that pulls inwards. This has a significant influence on the overall tension and centering of the rim.
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Carbon fiber is very strong in tension but much weaker in compression. When a tire is pressurized that puts the rim in compression and results in a smaller rim diameter. A smaller rim diameter reduces the spoke tension.
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Oh ok, I didnāt know about that, makes sense.
This is also true of the Nimbus Stealth2 aluminum rim. Without a tire/tube mounted, my Park TM-1 measures about 1-1.5 (unit-less) digits higher than with a tire mounted at 40psi. thatās about a 10-15 kgf difference.
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So that would have been a contributing factor in the tire blowout incidents over time (older Coker rims and more recently Nextie dont-inflate-too-much carbon rim) 
Thatās a very interesting point, a drop in spoke tension plus stretch over time in the tyre.
I wonder if this is just because of the size of the wheel, as my carbon rims on my uniycles 27.5 and 29," didnāt drop spoke tension after the tyre was inflated. Never experienced it either on aluminium rims either
Just wondering if anyone has a update on the performance on the light bicycle carbon 36 rim please
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Was the tire inflated to 40psi?
Hi @Tripthebalance,
A bit late, but I have finally given a try to this new carbon 36 rim. Mine has been laced into a freewheel 36er. I have ridden it for ~30 km of mixed XC, downhill, uphill and flat road. It has been really great. I canāt compare with the Braus rim right now as I have never ridden any freewheel with such a rim, but Iāll post a new message when my second rim will have replaced the Braus rim into my G36er. Probably during the next week 
As of now, the only pain point I have felt was to install the tire on the rim. As expected, it was quite hard. However, the tool I have linked before in this thread helped us a lot.
The tire was new, so I guess an already-used tire will be easier to install.
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