Are 28 spokes enough for 29+ rim

[asrama]

Hi all
 
I bought a Surly Krampus frame and want to lace new wheels. I would like to buy Raceface Arc Offset i40 29" rims and DT 350 hubs, but I'm not sure if i should go for 28 or 32 holes. I weigh around 165 lbs (75 kg) and will not carry more than 22 lbs (15 kg) food and equipment.

I want to use the wheels for long distance bikepacking like the GDMBR, OTT, AZ, CT, but also for mountainbike riding on rugged trails and rock gardens. Until now I have maybe broken 3 spokes in 20 years, but I've only ridden 26" wheels with 28 and 32 spokes.

I think that 28 spoke should be fine for my weight, but since I have no experience with 29" wheels I wonder if they will be strong enough and reliable.

What do you think?

[MikeC]

28 will likely be fine for a few years.  32 will distribute the load better, for longer.

The weight of 4 extra spokes per wheel is inconsequential.  But a broken spoke -- or several -- is real.

[bakerjw]

28 should be fine. 32 would be better though.

We run 36 on our mountain tandem and fully loaded it comes out to about 90#. 40 would be better, but Onyx only goes up to 36.

As wheels turn, weight transfers from spoke to spoke. The more spokes, the more even the transfer from one pair of spokes to the next. The added weight of 4 more spokes is very insignificant when it comes to overall wheel set durability. Surly bikes are by no means light so I'd go with more. Being the in the middle of BFE with a wheel issue is not a good place to be.