Bike Tech A says this - Tech B says this - who's right?

[Clancy]

Customer comes in with a broken spoke, MTB, set up tubless with Stan's

Tech A examines the wheel, tells customer the ammonia in the Stan's ate away at the nipples, weakening them and causing the broken spoke. Shows customer other nipples that show corrosion. Recommends wheel rebuild.

Tech B says the Stan's tape covers the nipples and they are not exposed to the sealant and that is not the problem.

Who is right?

[JAGI410]

Tech B.

[simplemind]

Tech B

[CNY rider]

Maybe they're both right.
Maybe the customer does need a wheel rebuild due to corrosion, but the Stan's wasn't the guilty party?

[-dustin]

carbon rim, alloy nipples?

any sealant leaking from the around the nipples?

[oldpotatoe]

Originally Posted by Clancy

Customer comes in with a broken spoke, MTB, set up tubless with Stan's

Tech A examines the wheel, tells customer the ammonia in the Stan's ate away at the nipples, weakening them and causing the broken spoke. Shows customer other nipples that show corrosion. Recommends wheel rebuild.

Tech B says the Stan's tape covers the nipples and they are not exposed to the sealant and that is not the problem.

Who is right?

Number B, Stan’s got rid of the ammonia a while ago plus don’t touch sealant. Aluminum nips DO corrode and break tho.m
But killing aluminum nips? Yup, rebuild with brass nips, just not the goop.

[Clancy]

Originally Posted by -dustin

carbon rim, alloy nipples?

any sealant leaking from the around the nipples?

Alloy rim, alloy nipples, no sign of leaking around nipples

[Gummee]

Originally Posted by oldpotatoe

Number B, Stan’s got rid of the ammonia a while ago plus don’t touch sealant. Aluminum nips DO corrode and break tho.m
But killing aluminum nips? Yup, rebuild with brass nips, just not the goop.

The trick is... how long ago were these wheels built and did they run old Stan's in em?

Could be both.

Regardless, if there's corrosion on the AL nipples, time to replace them. Better safe than upset (and walking out of the woods!)

...and I've been trying out the new Slime tubeless stuff. So far so good.

M

[oldpotatoe]

Originally Posted by Gummee

The trick is... how long ago were these wheels built and did they run old Stan's in em?

Could be both.

Regardless, if there's corrosion on the AL nipples, time to replace them. Better safe than upset (and walking out of the woods!)

...and I've been trying out the new Slime tubeless stuff. So far so good.

M

If the Stan’s was that old it would be a fuzzy rubber animal in the rim, not liquid.
N

[mcteague]

Non-anodized alloy nipples are very prone to corrosion from what I understand. Most quality brands, DT & Sapim, anodize theirs. I think a few of the early internal aluminum ones were not, thus the corrosion.

Tim

[Jaybee]

I'm inclined to go with Tech B as well, but...

... I have seen (perhaps in my own garage) a poor job of rim taping that allowed some sealant to get underneath and collect in the spoke holes where it dried out. this was brass nipples and no-ammonia home brew sealant, so no corrosion observed.

[Clancy]

Thanks everyone! I won a beer out of this!

(I'm tech b)

[-dustin]

Originally Posted by Clancy

Alloy rim, alloy nipples, no sign of leaking around nipples

i'm curious, now that we know you're tech B...

what does the rim look like at the eyelets? what about the valve hole? what is the actual rim model and what kind of valve stem? how was the tape pierced to allow the valve stem?

[benb]

Interesting... I've got a set of Mavic CrossMax XLs that are on their last legs.. lots of corroded nipples.

The wheels are just so tough for my usage + weight that I've been getting away with not replacing them as they are true/round enough to be fine and they're discs so no issues there.

I would have definitely run the old Stan's formulation in them, I've been putting Stan's in since 2009 or so I think. They are UST wheels though.. no tape or anything like that to worry about, but I would still expect some sealant to have gotten onto the nipples externally over the years.