[Finx]

I have a friend with a relatively new GR300 that has a loose rivnut on the bottle cage mount under the downtube.

Before we drill and replace it, I'm going to see if we can just tighten it.

Just curious what type of RivNut's are used here. I know they are M5 and .80, but they come in may types of metal. I suspect "Stainless Steel" is the correct answer, but there are other variations of steel and aluminum, so I thought I'd check here to see if anyone knows for sure.

Thanks in advance.

 

[GKSki]

McMaster-Carr has many varieties. I used their version for plastics and composites on an old Trek OCLV frame Worked perfectly.

Sans special tools, TLG offered this video,

 

[Finx]

I've seen the videos. I'm just wondering if Stainless is preferred to Aluminum for a Ti frame. I'm concerned about corrosion due to dissimilar metals.

 

[nova_rider]

I bought a used Litespeed Vortex with a stripped rivnut. When I drilled it out, it was aluminum. I sent that frame back to the factory to have it refurbished, and they repaired it with another aluminum one.

A bit surprised to hear about the GR300 as I'm currently building one.

 

[Finx]

Bit surprised to hear about the GR300 as I'm currently building one.

Pretty sure the issue was user error. He told me he cross threaded a bolt and the rivnut started spinning when he tried to get it out.

I'm hoping we can re-tap the threads and re-compress the nut, but I'm anticipating it will need to be replaced.

I built the bike for him and was pleasantly surprised at the workmanship.

 

[tlg]

I've seen the videos. I'm just wondering if Stainless is preferred to Aluminum for a Ti frame. I'm concerned about corrosion due to dissimilar metals.

I would use stainless. Nothing else.

 

[Finx]

I just got confirmation from Lynskey that they use Alloy M5 .80 RivNuts.

I picked up a couple of each (Stainless and Aluminum). Once I get my hands on the bike, I'll ponder this, and the rest of my life choices, and go from there...

 

[GKSki]

I can see where stainless would make more sense for your application. For CF I would opt for the aluminum as I would want it to compress and secure with the least effort and threat to the carbon fiber tube. I'm assuming stainless is more rigid than the aluminum and would better handle your dissimilar materials issue.

 

[nova_rider]

Stainless is harder than Ti, so one risks damaging the frame using stainless. Both Litespeed and Lynskey say alloy, so do you really want to chance it with stainless?

 

[tlg]

Stainless is harder than Ti, so one risks damaging the frame using stainless. Both Litespeed and Lynskey say alloy, so do you really want to chance it with stainless?

A SS rivnut isn't going to damage Ti.
Especially not because of hardness.

SS rivnuts are used in aluminum all the time to provide stronger threads.

Bollhoff Rivnut | Rivet Nut | Rivet Nut Original

The RIVNUT creates load-bearing nut and bolt threads on thin walls where cut threads are just won’t do the job. We offer a wide range of models, sizes, and materials (stee

www.rivetnut-original.com

The RIVNUT® installs blind in sheet metal, plastics, and tubular materials without deforming the parent material. It can also be installed into galvanized or pre-painted materials without damaging the surface finish.

If you can install them in plastic.... your Ti frame will be fine.

 

[Finx]

Stainless is harder than Ti, so one risks damaging the frame using stainless. Both Litespeed and Lynskey say alloy, so do you really want to chance it with stainless?

By this logic you couldn't put any kind of metal rivnut in a carbon bike.

I think the Ti frame will hold up fine to a SS rivnut.

Ill probably let the bike owner ultimately decide (once I make him aware of all of the pros/cons).