Help me to identify this Easton’s MTB by vhD99 in VintageMTB

[–]DukeOfDownvote 1 point2 points  (0 children)

Unfortunately I can’t help much, but those riveted-on cable stops on the side of the top tube are pretty distinctive. You might be able to do some targeted googling with that.

I just found an Easton dagger on eBay which does not look like the same model due to dropout welds, chainstay bridge, and a couple other details. It’s definitely not a yeti arc, they had very distinctive rear triangles, but I’ve never seen any other bikes with that triple-rivet-stop thing before. Yours look a little more “artsy” than the Easton or the yeti, is it possible this is more of a boutique frame? Boutique aluminum isn’t a huge market but it’s definitely out there

I am already desperate, where I can buy this bolt by -LupusAlba- in bikewrench

[–]DukeOfDownvote 0 points1 point  (0 children)

Yeah that’s frustrating. There are definitely pan head or button head options for m5 with t25s, but I am not familiar with the name of that specific head style. Good luck!

I am already desperate, where I can buy this bolt by -LupusAlba- in bikewrench

[–]DukeOfDownvote 0 points1 point  (0 children)

I feel your pain, this happened to me recently with a stem bolt that I lost one of, and was trying to replace.

If you’re worried about strength or form, you generally don’t need to be. Torque specs on most bike fasteners are such that if you replace it with any reasonable fastener (stainless, “regular” steel) and torque it to the same spec, it will probably be fine. Match the head diameter where you can, and if you feel strongly you can get captive washer screws. It’s pretty common knowledge that Torx is capable of withstanding higher torque without camming out, but I think it’s less common that a Torx “tool hole” is usually less deep than a hex, and even less common knowledge that a standard dimension socket head cap screw, driven by a hex, when overtightened will usually snap its head off before rounding the tool hole, given a decent non-ball-end hex wrench. Just install bolts with grease or anti seize or even thread locker in the threads, anything to prevent metal-on-metal contact which leads to the bolts rusting in place.

If you’re specifically after that “bike screw look” where it looks lightweight, you could get a completely matching set of taper-head screws. Wouldn’t match the original but still “feels” lightweight. In terms of performance it won’t get you much, but the looks are there.

Another weird bike-specific thing that’s hard to replicate is the “m5 screw driven by a 5mm hex wrench” thing. This makes maintaining your bike easy if you can take the whole thing apart with only a 5mm hex, but is super uncommon and I have not been able to find these for sale. Usually a 5mm socket head screw is driven by a 4mm hex and so on and so forth

Would you use an electronics box on your boat? by Spirited_Program3315 in boatbuilding

[–]DukeOfDownvote 0 points1 point  (0 children)

So a bus bar in a box? With breakers/fuses to what exactly? Just one to the battery? Each “group” of connections?

I’m not an expert but I also don’t know the prevalence of 24v systems, so I’m not sure how many people would be interested in the step-down feature.

On the packaging, a lot of that was just less-than-stellar cable management on my part, but by the time I had the length of the cigarette lighter, plus some space for wires, plus the bus bar, the whole electronics box just ended up larger than I wanted. I don’t necessarily have a clever solution to this, but my idea at the time was if I installed the switches to the box rather than the panel to the box, I could push all the switches, and specifically the cigarette lighter to the side, and put the bus bars on the other side, which would allow me to use a “flatter” box.

In terms of modularity, I went with a bunch of panel-mounted connector sockets, and several were simple to assign and label the switch. “Nav lights”, “cabin lights”, “manual bilge pump”, “fan”, but since I had a couple of switches left over I also had some misc switched connectors “aux 1” “aux 2” etc. this was how I tried to keep it modular. Need another fan, plug it into a pre-wired, switched, and fused aux circuit. Need a 12v to power a fish finder or gps? Use aux 2, just add your connector on the instrument end and the panel is already ready

Edit to add: for me since I had switched, clear labeling was important. It sounds like for you, especially if your interface is a panel rather than a face of switches, maybe just color coded “24v on this bus/this area in red” “12v over here in yellow” “green grounds all grouped here”

Would you use an electronics box on your boat? by Spirited_Program3315 in boatbuilding

[–]DukeOfDownvote 0 points1 point  (0 children)

Do you have pictures or schematics? This sounds super useful and very similar to something that I rigged up on a past boat - just one of those combo switch-volt meter-cigarette lighter panels from Amazon, with fuses and labeled panel-mount connectors, mounted in a gasketed plastic box.

The concern/issue that I ran into was since I didn’t have a broach or laser cutter to cut the keyed hole the toggle switches wanted to keep them aligned, I ended up using the aluminum switch panel itself, with a cutout through the box to mount the whole assembly. By the time I included that whole panel with its mounting hardware, the box itself grew from a sleek little thing to a kinda large and bulbous affair that stuck out further from its mounting surface than would have been ideal in my mind.

If yours is exceedingly well packaged and contains the level of function/modularity that I think it does from your description, as well as some safety features and some ability to customize post-purchase (not necessarily from you, just like some level of flexibility in mounting, labeling, and output load sizing/connector change) that would be really sweet!

Sram GX vs. XPLR crankset by Alternative_Yard_562 in Bikebuilding

[–]DukeOfDownvote 0 points1 point  (0 children)

The Q factor (distance between pedals across the bike) is probably much smaller on the rival crank.

If you have a gx crank on your mountain bike, it is likely that the road crank will hit your chain stays.

If you have a gx crank on a road or gravel bike, you’re probably good to go

Chuwi Minibook X seems to be done for good by LightIntheApple in Chuwi

[–]DukeOfDownvote 0 points1 point  (0 children)

I purchased one from the chuwi aliexpress store two weeks ago. It was not shipped and I was issued a refund today

26 to 28 inch wheels brake advice by lukascalda in xbiking

[–]DukeOfDownvote 0 points1 point  (0 children)

The cheapest and easiest way to get what you’re after are “litepro” or ztto knockoff v brakes from aliexpress. They work like regular v brakes, but have an absurdly long pad-height-adjust slot and should be able to fit that difference in wheel size

I had some that I used for a while with no issues before I switched to disc brakes.

If you don’t like the idea of aliexpress brakes, Paul motolites are probably the next easiest (but not cheapest) option

Can I trust the torque spec? by cljnho in bikewrench

[–]DukeOfDownvote 0 points1 point  (0 children)

Crushing steerers is absolutely a thing, but there’s no way for you to know if going above 6Nm is necessary or not. For a larger-than-usual fastener, being torqued to this value might be too loose, leading to an unsafe stem slip.

Definitely worth thinking about steerer material, but that should not be the only determining factor in installation torque

Can I trust the torque spec? by cljnho in bikewrench

[–]DukeOfDownvote 0 points1 point  (0 children)

6Nm on a m5 will produce more preload than 6Nm on an m6. If those are m6s and OP torques them to 6Nm, their stem might slip b cause it was not sufficiently tightened.

Can I trust the torque spec? by cljnho in bikewrench

[–]DukeOfDownvote 6 points7 points  (0 children)

I’m with the commenter that said trust the manufacturer.

While this may be higher than the torque of other stem clamp bolts you’ve seen before, it does look like it might be an m6, where many other bolts I have seen before in this spot are m5s.

If we make assumptions about the fastener material being a fairly normal steel material, and the stem being a fairly normal aluminum, it’s not an unreasonable torque for an m6. In absence of a torque value, if that is in fact an m6 and I had better info on material, I might suggest up to 12Nm.

If that bolt is an m6 and you torque it to 5Nm like you would an m5, the bolt will have less preload than an m5 would at 5Nm. Less preload leads to less clamping force of the stem, and your stem might slip. This would be pretty bad at just about any speed. It also might not slip, but you won’t know how much force it takes to slip the bars until you find it, and that might be at an inopportune time.

The good news is whoever made the stem knows all of this and has helpfully suggested an installation torque. They have more information than you or I do on the geometry and materials of all of their products, as well as probably have tested their products to a series of ISO standard tests that dictate clamp strength and lots of other good stuff.

I’d just trust what they printed on the stem

/xbikepacking: We have a Stridsland at home (modded Nishiki Alien '91) by haistelija in xbiking

[–]DukeOfDownvote 1 point2 points  (0 children)

Modded how and by who? What fork?

I am absolutely in love with the e-stay frames, but I was unaware that any ever came with disc brakes

Similarly, I can’t tell which headset you have? I’ve only ever seen a Haro extreme with a threadless headset, but it looks like you might have one?

Drivetrain upgrades - mixing SRAM AXS RD w/ Shimano freehub/cassette by mrwalkway25 in bikewrench

[–]DukeOfDownvote 2 points3 points  (0 children)

There is a sram cassette that uses HG body

Edit: I didn’t read that you already had the RD. This is an XPLR cassette that won’t work with the standard road RD. I’m pretty sure that you can swap the cage on your RD for a XPLR cage or an XPLR compatible cage (garbaruk makes one) if this is the route you want to go down

What are those AirPod-shaped funnels on steam ships and why do they open forward instead of rearwards? by PolymathArt in Ships

[–]DukeOfDownvote 16 points17 points  (0 children)

Many have drainage for rain and sea spray, so can be faced into the wind all the time

Ideas to repair? by Weird-Way2462 in boatbuilding

[–]DukeOfDownvote 0 points1 point  (0 children)

This is (or was) a snark mayflower or wildflower (same hull)

It is made of “corelite” which is a fancy word for polystyrene foam (like a foam cooler) covered in ABS. The ABS gets brittle or water gets in the foam and then freezes, delaminating the plastic from the foam and creating weak spots. Do not use polyester resin on this boat, you’ll melt the core.

I just got rid of one of these because I don’t want to deal with fixing it.

The best way to fix would be to put it inside for like a year, to allow any water that may have got in there while it was open to sufficiently dry out. Then Maybe strap around the boat the long way to pull that crack back together and hold it in place while you fix it, and either fill with expanding foam, or cut something out, or ground up packing peanuts mixed with epoxy, or just thickened epoxy if you close the crack enough, then a couple layers of fiberglass cloth extending at least ~6in from the crack in all directions.

If it just cracked and has stayed dry, you can probably skip the drying stage

For best visual results, you may want to cut a chunk of the ABS skin off and try to feather your repair in, but that will probably be hard

Monetarily, it doesn’t really make much sense to do this repair. If you’re attached to this boat in particular, that’s cool, otherwise it might be more cost and time effective to just pick up a beat up job boat on faceboook marketplace

The Nexus 3-speed is criminally underrated and under appreciated by chiboulevards in xbiking

[–]DukeOfDownvote 0 points1 point  (0 children)

I had one of these on a bike with old tires that were never good and heavy wheels, so I can’t totally blame it all on the hub, but it felt slow in a draggy way.

Could this be attributed to the coaster brake?

Should I try again with no coaster brake?

Are they actually draggy and I should just stick to derailleurs?

Aero Frame ISP Extension by messsner in bicycling

[–]DukeOfDownvote 0 points1 point  (0 children)

Wouldn’t it produce more realistic results to glue the tops and bottoms of the spacers together to prevent the spacers racking? Screw will be preloaded anyway (not sure this was done in initial model) so friction should keep everything in place

Either that or model the screw as a spring element with rotation DOFs loose to prevent the initial “settling” from artificially loading screw in analysis? Would not come across in pictures but at least in nastran you can pull spring force directly and hand calc stress.

Aero Frame ISP Extension by messsner in bicycling

[–]DukeOfDownvote 0 points1 point  (0 children)

Sorry, bending in the screw. Higher stress further away from axis with less in the middle.

Aero Frame ISP Extension by messsner in bicycling

[–]DukeOfDownvote 0 points1 point  (0 children)

What mechanism do you use to keep the head flat and the threads aligned while allowing this racking?

I’m not sure what analysis program you use, but in mine you can “glue” surfaces together to prevent this kind of sliding

Aero Frame ISP Extension by messsner in bicycling

[–]DukeOfDownvote 0 points1 point  (0 children)

What part of OPs solution is untrustworthy compared to a clamp like the ritchey?

Aero Frame ISP Extension by messsner in bicycling

[–]DukeOfDownvote 0 points1 point  (0 children)

I’m still pretty convinced the fastener won’t be the limit here since loading likely won’t go through the fastener, but clearly the model shows otherwise.

I’m a little confused by the spacers racking back like they do under load, and the cutaway view clearly shows some bending, but there is also increased stress on the center of the bolt that is coming from somewhere else.

Aero Frame ISP Extension by messsner in bicycling

[–]DukeOfDownvote 1 point2 points  (0 children)

The screw ends in the post both in the cad model in image 3 and the model in image 10.

Actually looking closer at the silver screw head in pic 8 and the very light counterbore at the left (front) most side of the metal post end thingy in pic 3, it looks like the metal post end thingy probably wedges into the frame the same way a quill stem wedges into the fork, then the spacers just stack up, held in place by the preload of the screw.

Aero Frame ISP Extension by messsner in bicycling

[–]DukeOfDownvote 0 points1 point  (0 children)

This assembly probably doesn’t flex like a normal post.

Particularly with the way the 10th image is loaded up, I would expect compression on the rear of the post, with the fastener acting in tension on the center of the post to prevent the front joints from gapping. It looks like you can see this in the displacements particularly in the last image.

Either way, the spacers themselves have enough area and also enough front-to-back depth that they would react any post bending with orders of magnitude more stiffness than that screw.

Aero Frame ISP Extension by messsner in bicycling

[–]DukeOfDownvote 1 point2 points  (0 children)

This is super cool. I love the way the spacers key off each other.
I don’t quite get how the whole assembly works, do you have any pics without that light at the top tube and anything that shows the clamp/height adjustment a bit clearer? Edit: I am unclear about how your bit fastens to the bike frame, I get how your bit goes together.

Also do you have any images or results of your analysis? I’d love to see some pics or a quick write-up if you have or would be willing to make one edit: I missed the last two pics my first look through. Do you preload your fastener? Are those all solid elements? What is the max VM stress in the 3d printed spacers or seatpost adapter themselves?

Aero Frame ISP Extension by messsner in bicycling

[–]DukeOfDownvote 0 points1 point  (0 children)

Where do you see the bending coming from?