V20 rusty nuts and bolts

[Black Hawk Down]

Anyone else out there have trouble with the V20 bolts rusting up, in some cases, enough to make it almost impossible to remove? Funny thing is, some of the bolts show no sign of corrosion, which tells me that poor quality steel bolts are being used in some places. I keep my bike indoors and wipe it down after getting wet (rare) from rain. My V20 is of 2016 vintage. Let me state for the record that I'm a big fan of Cruzbike and specifically the V20 and S40 bikes, which I own. In general, they seem to be of high quality and well designed, which makes me wonder why they would skimp on the nuts and bolts.

Bottom line is, I need to replace many of the bolts and I was wondering if this is a common issue, and if so, what are the recommended replacement materials/method? Here's a few shots of bolts that rusted while others have not:

This one has a rusty bolt and two with no corrosion, even though they both came with the bike 4-5 years ago.

 

[Pollock]

Your images are not coming through for me.

I have an S40 and have seen some bolts with the same issue. The ones holding my bottle cage on the headrest are getting there and I have one or two holding the seat in place. I do have a mix of bolts that came with the bike, with extra parts (bottle cage) and picked up from Lowes Home Store. I’m not positive which are which now

All of them seem to be caused by sweat staying around them. I’ll replace them on an upcoming weekend and try to find ones similar to those that are holding up.

 

[Black Hawk Down]

Your images are not coming through for me.

I have an S40 and have seen some bolts with the same issue. The ones holding my bottle cage on the headrest are getting there and I have one or two holding the seat in place. I do have a mix of bolts that came with the bike, with extra parts (bottle cage) and picked up from Lowes Home Store. I’m not positive which are which now

All of them seem to be caused by sweat staying around them. I’ll replace them on an upcoming weekend and try to find ones similar to those that are holding up.

I'll try to get the images up again. I put them in a shared photos folder, and they show on my browser.

One of the images shows bolts holding the slider in place. One is corroded and the other two are completely clean. No sweat reached these bolts.

 

[Robert Volk]

Yes! I got caught in a rainstorm once this year, the next day I had rust running down all the tubes from the bolts the v20 isn’t even a year old yet

 

[cpml123]

I thought bike bolts are all stainless steel. Guess I thought wrong. Darn.

 

[Lief]

That is a lot of rust. I’ve had several Cruzbike over the years, some ridden in all conditions and let drip dry - in the Pacific Northwest - none have ever looked anything close to that bad.

something is definitely wrong there.

 

[Mathew Fy]

Mine are mostly clean. Some bolts/screws have more surface corrosion than others, though. Stored in a basement, but occasionally overnighted outside & ridden in the rain. I've had no trouble removing anything, but I put either blue Loctite or grease on all the threads.

 

[Black Hawk Down]

That is a lot of rust. I’ve had several Cruzbike over the years, some ridden in all conditions and let drip dry - in the Pacific Northwest - none have ever looked anything close to that bad.

something is definitely wrong there.

I'm in Austin now but most of the time on the V20 was in Encinitas, near the ocean. Maybe salt? Still, some of the bolts have no corrosion at all. Gotta blame the materials.

 

[Black Hawk Down]

Mine are mostly clean. Some bolts/screws have more surface corrosion than others, though. Stored in a basement, but occasionally overnighted outside & ridden in the rain. I've had no trouble removing anything, but I put either blue Loctite or grease on all the threads.
View attachment 10229

I built my V20 from the frame set and used a light application of ParkTool grease on all the threads. Here's a shot of the headrest option. The screw was so frozen, I had to dremel two flats on the screw head so I could turn it with a crescent wrench.

Of course, sweat could be involved in this one.

 

[Frito Bandito]

Mine also has rusted as badly. When assembling my bike I noticed it and figured I have to fix the problem quickly because it doesn't look like a part that you can just run down to the Home Depot and replace with a stainless steel verson, which is exactly what I do for any part on any of my bike as soon as I notice that it starts rusting.
My advice is to take it off right now before it siezes, put it in rust remover, prime and paint the non-threaded parts, then use grease, Loc-tite or something else on the threaded parts before installing it again.

 

[Black Hawk Down]

Mine also has rusted as badly. When assembling my bike I noticed it and figured I have to fix the problem quickly because it doesn't look like a part that you can just run down to the Home Depot and replace with a stainless steel verson, which is exactly what I do for any part on any of my bike as soon as I notice that it starts rusting.
My advice is to take it off right now before it siezes, put it in rust remover, prime and paint the non-threaded parts, then use grease, Loc-tite or something else on the threaded parts before installing it again.

Thanks. I plan to replace all the corroded screws with new ones ordered on Amazon. rust remover, priming and painting is the best course of action. Unfortunately, I'm a severe procrastinator and very anti-maintenance. I love riding, hate maintaining. I do it purely out of necessity. My rant all started by the need to adjust my headrest. Then I took a look at the other screws and saw all the corrosion. Hopefully the new screws (304 stainless) will last longer. Someday, I'll have to throw away and replace my bike since it will be too ugly to sell. ce la vie.

 

[Frito Bandito]

It's a deep hole for sure. Some of them are easy enough to replace with stainless at your local DIY and it is far less hassle to do just that. However, that piece you mentioned, maybe I just haven't seen it at the DIY shops near me, but it doesn't seem so easily found off the shelf in Tokyo. I'll have a better look when time permits. Now, I take care of my stuff probably a bit too much. It is soothing, helps keep the resale value, keeps everything working well, is safer and keeps me out of trouble. Just be sure to give all of them a twist from time to time to ensure that they aren't coming loose.

 

[benphyr]

Salty, damp air (ocean) + steel + aluminum = best case for a redox reaction (rust = oxidizing in chemistry terms) and worst case for you.

Only the best quality stainless can stand those kinds of conditions for long. Different applications call for different material qualities such as hardness, corrosion resistance, etc. Some of the parts might need properties not easily or cheaply available in stainless and might be plated or galvanized instead providing good qualities for most situations but not best qualities that your situation would require for longevity.

The headrest clamp is an accessory isn’t it? And so is not part of the same manufacturing process. It definitely appears as though this part is Aluminum with a steel bolt going through it. Not ideal from a corrosion resistance perspective but likely a good compromise between cost, functionality, weight, ease of manufacturing, simple design, etc.

 

[3bs]

Resale value? That would imply n-1 . Wtf?

 

[Black Hawk Down]

Salty, damp air (ocean) + steel + aluminum = best case for a redox reaction (rust = oxidizing in chemistry terms) and worst case for you.

Only the best quality stainless can stand those kinds of conditions for long. Different applications call for different material qualities such as hardness, corrosion resistance, etc. Some of the parts might need properties not easily or cheaply available in stainless and might be plated or galvanized instead providing good qualities for most situations but not best qualities that your situation would require for longevity.

The headrest clamp is an accessory isn’t it? And so is not part of the same manufacturing process. It definitely appears as though this part is Aluminum with a steel bolt going through it. Not ideal from a corrosion resistance perspective but likely a good compromise between cost, functionality, weight, ease of manufacturing, simple design, etc.

I agree with everything you said, which confirms that not all the screws on the V20 are made with the high quality, rust resistant materials. In one of the pics that I provided there were 3 screws. One was totally corroded and the other two were clean. All exposed to the same environment and connected to the same materials for the same amount of time. The head rest bolt is an accessory, provided by CruzBike. I assume they stand by the quality of their accessories. These bikes are priced at the premium end of the spectrum. And for the most part, are high quality, high technology equipment. Just seems that they are overlooking some of the nuts and bolts. Quality stainless bolts are not that much more expensive. I know as I'm purchasing some as replacements.

 

[benphyr]

The two stainless are standard stem clamp bolts readily available. The slider clamp bolt and sleeve are more specific - if you found a good source for that one please let me know.

 

[velocio]

I agree with everything you said, which confirms that not all the screws on the V20 are made with the high quality, rust resistant materials. In one of the pics that I provided there were 3 screws. One was totally corroded and the other two were clean. All exposed to the same environment and connected to the same materials for the same amount of time. The head rest bolt is an accessory, provided by CruzBike. I assume they stand by the quality of their accessories. These bikes are priced at the premium end of the spectrum. And for the most part, are high quality, high technology equipment. Just seems that they are overlooking some of the nuts and bolts. Quality stainless bolts are not that much more expensive. I know as I'm purchasing some as replacements.

Black Hawk Down, you seem to be conflating "high quality" with "stainless", but as Benphyr very correctly pointed out:

Different applications call for different material qualities such as hardness, corrosion resistance, etc. Some of the parts might need properties not easily or cheaply available in stainless and might be plated or galvanized instead providing good qualities for most situations but not best qualities that your situation would require for longevity.

Perhaps Cruzbike just cheaped out on that "boom bolt" that rusted for you (but doesn't appear to be a common rust issue), but perhaps a stainless bolt formulated for extreme corrosion resistance lacked other material qualities important in that application. For example, many stainless steels are very hard, but not all that strong and more prone to cracking, especially when subjected to sheer forces, such as I suspect that boom bolt experiences. Maybe Cruzbike doesn't know what they're doing or are just cheap, but it's also possible that the boom bolt was spec'ed in a material other than stainless for a reason.

In the photos it looks as if the boom bolt, and area around the bolt, has physical damage, other than corrosion. The area around the boom bolt and the headset spacers appear to have damaged finishes, like the area was scratched or banged up somehow. If so, the plating on the head of the boom bolt may have also been compromised, leading to the corrosion shown in the photo. How did the headset spacers and such get so chewed up? That seems like an area relatively well protected from impact damage.

My S40 is 3.5 years old and has zero signs of corrosion on any bolts, including the bolt on the optional headrest. I guess I've been lucky ... I do agree that some of the nuts'n bolts supplied by Cruzbike seem like odd choices. The bolts that hold by seat back to the frame "ears" are at least 3x longer than needed. Or, they were 3x longer than needed until I replaced them. Also, the nuts were just plain nuts and there were no washers of any sort between the bolt head and the carbon fiber seat. I assume that was all some kind of mix-up, Cruzbike couldn't have spec'ed it to be shipped that way.

If anyone wants to talk about the deraileur hanger I have a few thoughts on that finely crafted bit of precision CNC'ed aluminum as well!

-Jack K.

 

[MrSteve]

Each one of our bikes lives in its own unique microclimate and so does mine.
In East TN, my bike (the one pictured in my avatar) lives for its next sortie in the garage.
The garage is always damp.
When it carries me outside for adventure-time, it must deal with corrosive sweat.
Here's what kind of works, for me:
All the bolts that hold the seat pan to the frame and the bolts that hold the bottle cage
(I bought the bottle-cage bolts/nuts/washers to replace the terminally rusted stock steel)
to the seat pan are stainless.
So far, those stainless fasteners remain stainless.
The bolts that keep the front-end together are plated steel.
All of those bolts show surface rust, rust limited by weekly polishing with the oily rag after checking torque.
The skewers that secure the wheels are steel, are checked yearly, and are coated with a high-quality oil.
The steel spokes on the stock wheels exploded last Winter. I never thought to check/maintain them. Ooops.
And that's that.
There are better-quality plated steel fasteners out there for sure, but as long as the stock parts still work, I'm good.

 

[benphyr]

...
In the photos it looks as if the boom bolt, and area around the bolt, has physical damage, other than corrosion. The area around the boom bolt and the headset spacers appear to have damaged finishes, like the area was scratched or banged up somehow. If so, the plating on the head of the boom bolt may have also been compromised, leading to the corrosion shown in the photo. How did the headset spacers and such get so chewed up? That seems like an area relatively well protected from impact damage.
-Jack K.

I think most of what we are seeing is just dirt and/ or salt thrown up by the front wheel. My cleaning routines are closer to annual than weekly or per ride and there is often dirt that can masquerade as damage. Also possible in high salt environments is aluminum breaking down and bubbling the paint. It kind of looks like white powder underneath. My winter mountain bike gets salt, water, and snow mix together with temperature extremes of -20C and outside storage at work to +5 or more and heated garage storage at home. Combined with infrequent cleaning and no extra protective treatments it lasted ten years without issues except for replacement of brake system and regular maintenance items of drivetrain and cables and housing. Now I have replaced the frame and expect another many winters.

 

[Black Hawk Down]

Black Hawk Down, you seem to be conflating "high quality" with "stainless",
-Jack K.

Well.. I guess I could have been more clear on this. While there are many material properties to be considered when choosing the right ones for the bike, I'm pretty sure all the requirements of a CruzBike can use nuts and bolts that are both hard, strong and have a high level of rust resistance. I've owned 3 other high end bicycles of the same cost level (~5k) as my V20 and S40. None of these bikes experienced a rust problem. In one case the bike was 18 years old and I rode it all over California. No rust. My point is, I think that appropriate nuts and bolts can be chosen with the necessary structural specs and don't rust. This isn't a rocket ship.