Alpha 340 or Pacenti SL23

[PhilWalterNZ]

I have a set of Campy Record 10sp 32 hole hubs, currently laced with heavy spokes to Open Pros.

Looking to rebuild with Sapim CX-Ray onto either the Alpha 340 or Pacenti SL23 rim. I weigh 75kgs ( 165lbs), and do a fair few miles each week often on roughish roads.

Just wanting something lighter then the current build and durable, and either of those two rims seem to be up to the task and would give me a lighter wheel. Whatever I do is probably going to be overbuilt anyway with 32 spokes !

Would welcome any opinions either way

[Zen Cyclery]

If the Pacentis came in a 32h I'd say go that route but I believe the highest hole count that you can get those in is 28h.

These rims really are drastically different from each other though. I've always viewed the 340 as more of a climbers hoop whereas the SL23 is more of a daily driver.

[PhilWalterNZ]

I do like my climbing And opinion seems to be the softer 340 is better when overbuilt.

Actually looking at the manufacturer claimed weights - the Open Pro is slightly lighter then the Pacenti.

Another option would just be to replace the heavy spokes to drop some weight.

[btompkins0112]

What about Kinlin XR19w in 32? Should be plenty durable with CxRays.

[Zen Cyclery]

I think the XR19w is way too soft of a rim for this build.

Even though the SL23 isnt lighter than the OP, it is a bit wider which will make it slightly more predictable in the corners. The extra depth should only add to that stability as well.

[bikerjulio]

Pacenti does come in 32H at BHS anyway.

I happen to have built for myself both an Alpha 340 and a Pacenti wheelset.

In terms of rim quality, ease of build, and the stability of the builds, it's no contest - get the Pacenti. You will not regret it. I used Lasers with no problems at all. Just did the usual stress relieving during the build.

[bm0p700f]

Velocity aeroheads will work or the DT Swiss RR415 if you can find them now. OP rims are light. Try the Kinlin XR-200's.

If a stiffer rim is required and you want it to be in the 450g region then why not the DT Swiss RR440, a fantastic rim. Built with them a few times now and every time I get that want feeling.

[kulivontot]

340's are super light, and have a pretty wide bead width.
But, there are reports of non-tubeless clincher tires randomly exploding off the rims.
And they're definitely not a stiff or durable rim.
People seem to love the SL23's... I guess they're the lightest wide rim you can buy. And don't seem to be as noodle-like as stan's or kinlins.

[ergott]

I've built many 32 SL23s. I think it's a better option. There's more material at the brake track and they are stiffer.

[PhilWalterNZ]

So my next question is..... Do I have much to gain moving from the open pro to the pacenti other than weight !

[bikerjulio]

So my next question is..... Do I have much to gain moving from the open pro to the pacenti other than weight !

Funnily a lot of my previous wheel builds and riding was on OP's, and I still have a few sets.

Major difference would be a better (perhaps faster too), ride because of the increased tire volume. 23's will look and act like 25's. 25's are like 28's.

Pacenti is probably more aero too.

[bm0p700f]

The SL23 is as wide internally as the archetype and I have yet to find a 25mm tyre on these that comes up like a 28mm. Then again I find most 28mm tyres come up narrower too.

[bikerjulio]

The SL23 is as wide internally as the archetype and I have yet to find a 25mm tyre on these that comes up like a 28mm. Then again I find most 28mm tyres come up narrower too.

Not really sure what that means. Most tires measure differently than their nominal width. My 25mm tire is a lot closer to 28mm wide than my 28mm tire.

FWIW a "25mm" PR4 on my Pacenti measures 27.7mm.



a "28mm" Conti on an Open Pro measures 26.8mm

[weenie]

I'm having similar troubles choosing rim/spokes/etc for a CX, generally need more spokes (24/28 for my 165lbs) and i of course prefer a stronger and stiffer rim.
Choices are IronCron, Alpha340, A23s, or hoop-build SL23.. at least from what I found so far.
(Mainly I like the 23mm+ width and the slightly deep rim for the mud).
Those are meant to be my everyday training-commute-all-the-things wheels.

It seems to me going with the SL23 would also be the best choice, although i've not read many reports of the IronCross either.

[madsry]

bikerjulio: Thanks for the photos. I have been thinking a lot about my next, well I should say my first real wheel build. After reading about the new HED wheels (which seem a bit too expensive for what they are) and one of their employees talking about running 23mm tires on them, I can't stop thinking about doing something similar via the SL23's. Seems like running a wide enough rim with 23mm tires more or less equals a 25mm tire on a moderate width rim without the weight penalty. Like having your cake and eating it too, no?

I'm still hoping that he Aredennes rim becomes available separately, although the SL23 may be just as good and will very likely be much cheaper...

These thoughts are all with road tubeless/disc wheels in mind.

I'm assuming that the IronCross wheels may not be safe at 80-85 psi. If they could handle the psi, it seems like they might be ideal for a road disc build.