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[skaredshtles]

<snip> Failing that, is there any way to troubleshoot a valve core short of just sticking a new one in?

Soapy water

[D(C)]

Eating crow about my Kryptotal and on a roll with dumb questions: I cannot keep air in my front tire. It's losing at least 10lbs/24hrs. Not a fast enough leak to lose air while riding but still kind of annoying. I've tried adding sealant twice to no avail. Going to try breaking and reseating the bead, are there any special tricks to get it to seat properly? I typically use an air compressor to do the job. It's like I got 99% of the way there... But just short. Failing that, is there any way to troubleshoot a valve core short of just sticking a new one in?

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I bet it’s damaged tape. If air is coming out the spoke holes or around the valve stem, that’s probably the culprit.

[Andeh]

I bet it’s damaged tape. If air is coming out the spoke holes or around the valve stem, that’s probably the culprit.

Seconding this.

[Andeh]

When going over my bike in advance of this coming weekend's road trip, I discovered the lower brake mount on the fork is more than halfway stripped out. For now, I've put in the longest bolt that will fit ~30mm, had a 25mm in there before, with a shitload of loctite. I'd conservatively guess there's only about 5mm of working threads. So, a couple questions:

1) Zeb 29 lowers are out of stock everywhere. Is SRAM/RS likely to have a secret stash of them that my local shop might able to access through service rather than b2b?

2) is there any way to repair this that will preserve the ability to remove the brake caliper? I.E. not fill the hole full of JB Weld

3) how crazy would I be to ride it in the current state? Part of me thinks that's fucking stupid, the other part thinks if I hadn't gone over the bike yesterday, I would have kept riding it as it was unawares.

For the record, I don't think that I did the damage, but I can't prove my theory, and bringing it up to the shop in question will result in either hurt feelings or blanket denials. I had them build up a bike with this fork, and when I got it back, I found multiple glaringly bad things wrong, including loose bolts and the front brake was mounted with with a +20mm adapter, for a 200mm rotor and a 200mm native post mount fork. The brakes were takeoff Code Rs, and I know the rear of those calipers makes it hard to screw the bolt in straight. When I later swapped the fork out, I remember noticing that it was really difficult to get the lower bolt out (must have been cross threaded).

[Robik]

When going over my bike in advance of this coming weekend's road trip, I discovered the lower brake mount on the fork is more than halfway stripped out. For now, I've put in the longest bolt that will fit ~30mm, had a 25mm in there before, with a shitload of loctite. I'd conservatively guess there's only about 5mm of working threads. So, a couple questions:

1) Zeb 29 lowers are out of stock everywhere. Is SRAM/RS likely to have a secret stash of them that my local shop might able to access through service rather than b2b?

2) is there any way to repair this that will preserve the ability to remove the brake caliper? I.E. not fill the hole full of JB Weld

3) how crazy would I be to ride it in the current state? Part of me thinks that's fucking stupid, the other part thinks if I hadn't gone over the bike yesterday, I would have kept riding it as it was unawares.

For the record, I don't think that I did the damage, but I can't prove my theory, and bringing it up to the shop in question will result in either hurt feelings or blanket denials. I had them build up a bike with this fork, and when I got it back, I found multiple glaringly bad things wrong, including loose bolts and the front brake was mounted with with a +20mm adapter, for a 200mm rotor and a 200mm native post mount fork. The brakes were takeoff Code Rs, and I know the rear of those calipers makes it hard to screw the bolt in straight. When I later swapped the fork out, I remember noticing that it was really difficult to get the lower bolt out (must have been cross threaded).

I would try to clear the threads with the tap. Then helicoil if it's damaged beyond re-tapping. BTW, I had same issue with one of the earlier ZEB brake mount that I bought used.

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[Roxtar]

I bet it’s damaged tape. If air is coming out the spoke holes or around the valve stem, that’s probably the culprit.

Seconding this.

X3
Pretty much every TL failure I've had has been tape related.

[Roxtar]

I would try to clear the threads with the tap. Then helicoil if it's damaged beyond re-tapping. BTW, I had same issue with one of the earlier ZEB brake mount that I bought used.

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Helicoil is a great permanent fix. Threads will now be steel instead of alum.
Just be careful on the drilling out process. Drilling aluminum slightly oversize tends to grab the bit, causing it to drill deeper or off angle.

[Andeh]

Helicoil is a great permanent fix. Threads will now be steel instead of alum.
Just be careful on the drilling out process. Drilling aluminum slightly oversize tends to grab the bit, causing it to drill deeper or off angle.

Thanks guys, I'll look into it.

[rideit]

Just had a ‘hail Mary’ repair thought.
If the threads are beyond pooched, theoretically, one could epoxy/JB weld a longer threaded rod into the fork mount, and secure it in reverse, with a nut at the end of it instead of a bolt head.
Just a wild thought.
Something I would try for myself as a last-ditch effort.

[J. Barron DeJong]

Just had a ‘hail Mary’ repair thought.
If the threads are beyond pooched, theoretically, one could epoxy/JB weld a longer threaded rod into the fork mount, and secure it in reverse, with a nut at the end of it instead of a bolt head.
Just a wild thought.
Something I would try for myself as a last-ditch effort.

JB Weld can be drilled and tapped, so you could fill the current hole completely and start fresh if you were inclined to go the JB Weld route.

[Roxtar]

JB Weld can be drilled and tapped, so you could fill the current hole completely and start fresh if you were inclined to go the JB Weld route.

Way, way harder to get holes drilled and tapped correctly than helicoil.

[toast2266]

X2 on helicoil. It's really the only viable repair option for that situation.

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[J. Barron DeJong]

Way, way harder to get holes drilled and tapped correctly than helicoil.

For sure. I’d be going heicoil.

Just saying that if you ended up going the JB Weld route for whatever reason, it can be drilled and tapped, which gets you back to where you started.

[XXX-er]

it IS a brake part and brakes are kind of important

[toast2266]

JB weld repairs are for areas that won't kill you if they fail. Maaaaybe a rear brake mount. Definitely not a front brake mount.

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[Andeh]

Helicoil installed, piece of cake. Hardest part is keeping the 1/4" drill bit from advancing too fast. Thanks for the help guys.

[scrublover]

When going over my bike in advance of this coming weekend's road trip, I discovered the lower brake mount on the fork is more than halfway stripped out. For now, I've put in the longest bolt that will fit ~30mm, had a 25mm in there before, with a shitload of loctite. I'd conservatively guess there's only about 5mm of working threads. So, a couple questions:

1) Zeb 29 lowers are out of stock everywhere. Is SRAM/RS likely to have a secret stash of them that my local shop might able to access through service rather than b2b?

2) is there any way to repair this that will preserve the ability to remove the brake caliper? I.E. not fill the hole full of JB Weld

3) how crazy would I be to ride it in the current state? Part of me thinks that's fucking stupid, the other part thinks if I hadn't gone over the bike yesterday, I would have kept riding it as it was unawares.

For the record, I don't think that I did the damage, but I can't prove my theory, and bringing it up to the shop in question will result in either hurt feelings or blanket denials. I had them build up a bike with this fork, and when I got it back, I found multiple glaringly bad things wrong, including loose bolts and the front brake was mounted with with a +20mm adapter, for a 200mm rotor and a 200mm native post mount fork. The brakes were takeoff Code Rs, and I know the rear of those calipers makes it hard to screw the bolt in straight. When I later swapped the fork out, I remember noticing that it was really difficult to get the lower bolt out (must have been cross threaded).

As others have said, Helicoil it. Super easy, durable, and waaaaaaay less money than new lowers!

Did that to a Lyrik lower years ago. Rode it several more years before selling it on, and the buyer is still using it without issues.

[Roxtar]

it IS a brake part and brakes are kind of important

Meh, brakes just slow you down.

[ZomblibulaX]

So I had to put my bike inside the subie as I made a few stops in SLCizzle recently, and the excessive heat appears to have pushed mineral oil past the piston on my front brake (shimano M8000). Leaked all over the back of the vehicle. Pads are still at ~80%, lever feels solid but it needed a bleed before this happened. There doesn't appear to be any additional leakage while pulling the levers.

These things are old (2016) and have a ton of miles, is it time to retire them? Is a bleed likely to fix this issue? I know shimanos don't have the tightest seals. Any great deals on brakes out there?

[rideit]

Glad you got it figured out, and didn’t try something like this:

[rideit]

Posting here because this thread seems to get the most consistent traffic. Last year, I came up with a safety idea. It turns out that a Mylar emergency ‘blanket’ fits perfectly in the underside of tapered steer tubes. Pretty much jams in there tightly enough that it won’t come out.

I made a little round gorilla tape dust cover, buts not really necessary.

Could save a life!
(Also can be used as a reflective device for S&R visibility)

[Duffman]

Any insight into whether these NOS OEM Manitou forks are legit or not? Want to get a lightweight 26" Markhour or something similar for the groms 24" bike.

https://www.pinkbike.com/buysell/2852883/

[Thaleia]

Front wheel on my Giant Contend AR4 has some side to side play, almost 2mm's worth either way. I have somehow never had to do any type of hub maintenance - would a preload adjustment typically address this or should I do a full tear down to inspect bearings?

Hub has about 2,500 miles on it.

Given it's a lowly S-R2 I'm guessing the latter and probably replacing the bearings but have zero knowledge and am curious while I wait for the spanner to arrive.

[sfotex]

So I had to put my bike inside the subie as I made a few stops in SLCizzle recently, and the excessive heat appears to have pushed mineral oil past the piston on my front brake (shimano M8000). Leaked all over the back of the vehicle. Pads are still at ~80%, lever feels solid but it needed a bleed before this happened. There doesn't appear to be any additional leakage while pulling the levers.

These things are old (2016) and have a ton of miles, is it time to retire them? Is a bleed likely to fix this issue? I know shimanos don't have the tightest seals. Any great deals on brakes out there?

There's a bladder in the lever that can get a pinhole in it and lets the brakes sort of works. If you bleed them you will find out really quick. You can get a (overpriced) spare off Amazon for $15 if this is the case. Had a small leak appear in mine a few weeks ago.
Otherwise, if you like Shimano you can upgrade to the 4 piston SLX or XTs that are floating around for not too much.

These Codes are the best deal I've seen, I got a pair for my Revel Rail:
https://bikecloset.com/product/sram-...t-mount-black/

[singlesline]

Glad you got it figured out, and didn’t try something like this:

I mean, that's dumb AF and I would never do it...

...but the force vectors on a brake caliper mount are mostly a pushing force between the faces with a bit of shear. There's not really much pullout force acting on the threads.

So I could see that working OK in an emergency...and that's probably exactly the hole I would choose if it were a case of broken/lost bolt where you could swap bolts around until you are only missing the back bolt on the rear.