light bicycle carbon rims

I’ve just pulled the trigger on some 27mm hookless 29er rims so we’ll see how they go. I went quite light as my 29er is weenie.

mine are going strong 2 years on, tubeless is a PITA though, any schwalbe tyre is like a wizard sleeve, built up with yellow tape but still difficult, but sounds like this isnt an issue anymore, considering some nextie hookless, among the million and one things i “need”

I’ve been running 35mm 29er rims since April last year and I’m still chuffed to bits with them. They just get on with their job of being a relatively light, stiff, wide and strong rim. I’m planning on building a pair for the Bigwig next and I’m pretty sure I’ll be sticking with 35mm.

38mm rims only give an extra 1.6 mm internal width for an additional 40g over the 35mm.It does mean the rim beads are thicker though by what, and extra 0.7 mm each. I’ve no doubt they’re stronger, but for me, the point of diminishing returns has been reached. I’m planning on ordering some at the end of January, but I’ll be ordering 35s.

Annoyingly they only seem to sell the 38mm via ebay, which would avoid their paypal fee. I see tenacious doug has been emailing them regarding the other befeits of a 38mm rim, so be interesting to see what they come back with.

scienceofficer i was talking to them on web chat today and she warned there will be a delay because of chinese new year apparently, so order sooner rather than later. not sure how true this is but way back on this thread i think some folks were delayed because of it. I’m going to order soon i think.

Yeah, it was the same last year. I’m not in any rush.

For anyone interested I’ve been working on a Rim tape solution for our new carbon wheels and have found a really good gorilla tape replacement were now buying in – 25mm wide but really good for 30mm+ rims, leaves much less mess than gorilla if you need to remove it and bonds well with the carbon surface for a good seal first time. Will be available from our store (shop.birdmtb.com) next week.

Do you get stung for import duty on the rims?

Yes. Vat and import duty is around 25% plus a customs handling fee of around £15 normally.

Cheers Ben

I plan to use hope pro II hubs any recommendations on spokes?

The benefit of carbon rims is they don’t bend like aluminium ones, so you can go really light if you want. Sapim leader or cxray, dt supercomp or revolution, or if you don’t mind waiting the excellent pillar range is available from top venturer in Taiwan in small quantities at a price that makes it worth shipping them in.

Cheers again Ben all being well these are going onto one of your frames!

Do you get stung for import duty on the rims?

You take your chance, I bought rims and spokes and got no charges.

did you hear anything back from LB Doug?

what weight do the 29er xc rims come in at as a complete build?

Some info but not everything I asked them. They suggested the 38mm was 10-20% stronger than the 35mm. I have asked specific information on the stiffness between the two, apparently they have lab tests that will give me this info but I’ve not had them sent through yet.

what weight do the 29er xc rims come in at as a complete build?

Depends how you build them…

Mine with American Classic hubs and Revolution spokes are 1370g.

Annoyingly they only seem to sell the 38mm via ebay

The 38mm are on their website, I ordered them a couple of weeks back and they are still there.

crikey that is light! What kind of cost are we talking about for that, and did lb build them or did you just order the rim

Whats the durability like for everyday xc riding..im around 80k, have been using crest 26ers for past few years with no issues whatsoever

I’ve got the 29er 35mm rims which came in about 415g and have been fine. 28 hole and built up on DT 240 hubs with revolution spokes. Came in about 1450g.

Looking at building up a set of 25mm road rims on DT 240s again and will likely come in about the same weight of my 29er MTB wheels scarily enough. Anyone tried the road rims at all?

The 38mm are on their website, I ordered them a couple of weeks back and they are still there.

Sorry MSP i meant they only sell the 38mm on ebay and not the 35mm too. i know you can order 35mm direct from the site but i think that incurs a paypal fee. torn between the 38’s & the 35’s now.

have you got your 38’s yet?

What kind of cost are we talking about for that, and did lb build them or did you just order the rim

Whats the durability like for everyday xc riding..im around 80k, have been using crest 26ers for past few years with no issues whatsoever

About £600 or so I guess – I bought hubs from the US (AEBike.com), and spokes from Germany, and built them myself. Rims were 355 and 356g – if you’re bothered you can ask for light ones (I did).

If you’ve been fine on Crests you won’t need anything tougher – they’ve been faultless, I’d have another set without hesitation.

I bought a 27mm and 30mm for rear and front, built with Extralite front hub and AC rear, DT Rev spokes, 2 cross. 1320gram without tape.

Most bike shops / experts advised against DT Revs, alloy nipples, 2 cross etc. Big test tomo on its maiden run.

have you got your 38’s yet?

No, they have just gone through customes today, should have them sometime next week.

I have gone for the full downhill version, so not really saving much weight on a set of stans flows, but should be much stronger and wider.

cool, i’d be interested to hear what you think of them!

Has anyone had any build issues. I got some over 6month ago but only just got round to getting hubs and spokes. On building up found 1 spoke nipple on each rim would not seat properly. Inside the rim seems to have a load of excess carbon which makes it thicker and not smooth at that point. Also one of those holes is drilled slightly skew.

Need to contact LB I think

Here’s some Info LB sent me on comparative test figures between the 35 & 38. They are pretty self explanatory. Impact strength and positive stiffness (which I assume is vertical stiffness) is much better than the 35, while lateral stiffness is similar.

I’m not an expert in wheels but my thought is the greater lateral stiffness will be offset by the lower spoke tension so my slight concern about these perhaps being too stiff is not an issue. Plus I don’t expect to notice the lateral stiffness difference.

So overall, 38s should feel similar, with greater strength, marginally more weight but look much more badass because of the depth!

thanks for following this up Doug, much appreciated. look like i will be snaffling some 38’s off ebay tonight then!

Interesting stuff. If I’m reading it right, It should be that the 35 shares more of its impact force with the rest of the wheel structure as it deforms twice as far as the 38, which should compensate a bit for its overall weaker structure.

Can anyone recommend an experienced wheel builder for these?

I had mine built onto existing Hope hubs by 18 Bikes in Hope. They did an excellent job with them.

Where you based fudge? My bother in law built both of mine, he’s north east based

Cheers I’m in Northern Ireland so will need to courier them, will make a few phone calls next week, mine will go onto hope Pro2 EVO hubs aswell. Any recommendations on spokes.

I used DT revolution

Fudge you need Norms Bikes in Belfast. Top job and easy to pay.

crispyrice cheers for that, just 25 miles away from me, I’ll give them a call on Monday.

I built my own. Been building for a few years but by no means a pro. Just take me time. Really enjoy building these as they go together really nicely. Only done 28 hole with revolutions so there’s easier options to build too.

Come on surely someone’s tried the road rims, any thoughts on the 25mm x 35 mm anyone?

I bought the 650B 35mm version and have had them on the bike for about 3 months. Unfortunately while washing the bike (after two full days of riding this weekend) it appears that my rear rim has a small split/crack.

I wouldn’t be able to say how it happened as it’s been pretty uneventful, I’ve been doing small to medium jumps and drops (nothing big) but didn’t crash it.

I’ve emailed LBC with photos so I’ll see what they say / find out what their support is like. I also only have the one bike so now I can’t ride for however long its going to be…

Slightly worrying! I think I will wait to see what the customer support is like before purchasing, keep us informed.