Rim construction question
I've been talking to my local shop about having some touring wheels built and they suggested using the Mavic A319 over the Mavic A719. The 319 rims are about $30 less each.
Both rims are double-eyeletted. The main differences seem to be 1) A319 is a little heavier (and the cross-section drawing in the catalog looks slightly different), 2) the joint is formed differently--on the A719 it's welded and milled, and on the A319 it's something else (not described on the website).
So my question is if the A719 specifically says it's welded, how is the A319 constructed? What are practical differences?
Or should I just go with the Velocity Dyad (closer in price to the A319)? (And as a complete tangeant, how do you pronounce Velocity--like the synonym for rate of travel or like a bicycling burg?)
i think their economy riims (2,3xx series) are pinned only. the fancy ones add a weld followed by grind. it doesnt affect strength much or longetivity of the wheel.
it can leave a little bump at the seam which you'll notice if using rim brakes. this may eventually disappear with use/wear. maybe not if esp. poor joint alignment. it'll definitely drive you nuts if you are a meticulous wheel builder.
afaik, all velocity rims are pinned only. probably other brands too.
According to Brandt, solid rims are welded, and box section rims, particularly large crossection ones are likely plugged. He does not express a preference in my edition.
I thought this was one of those luddite issues were the pinned joint is better? My sainted MA2s are pinned.
The 719 seemed on the site pictures to have more of their weight in the braking areas. while the 319 seems to have a tunnel feature for strength but less braking area. It would be of interest if the 719 was better designed for braking and heat absorbtion, as to some extent the milled and welded rims seem to point in that direction whether really neaded or not. The 719 seems to have a 40 spoke option that while it isn't probably what you want, again, is a touring specific rim feature. I got al three of the 719, 319, an Alex DH22 up on the screen and the DH22s that I am running are very similar to a cross between the 310 and the 719. Internal tubes, but deep rim with thick braking surfaces. And the DH are cheap. http://www.alexrims.com/ then search on DH22.
One feature you want is an easy to change tires on rim. Deep usually helps but there are lots of factors. DH22 is very easy to change. You can go like 2000 miles and no flats and then have to change the tire four times in one rainy day.
There are a lot of factors I can't really gage from the slight info rim makers put up, but I would go 1) 719, 2) DH22 3) 319.