soyabean

I can make these M8 seatpost binder bolts by welding a piece of spoke to it.

I'm looking for a bulk source for these where I can buy 50-100 per order.

I need only the bolt. I do not need the washer. I do not need the acorn nut.

There appears loads of them on auction sites, but I am not interested in buying retail as my target price for this bolt is under $1.

Ali appears to have only the upgraded binder bolt, which requires a tool on both sides, the same as using a regular M8 bolt and nut.

This binder bolt is commonly found on all big box store bikes from all eras, past to present.

The reason why I must include this binder bolt with the bikes that need it is because it eliminates calls I get from clients that only own one monkey wrench and they keep asking me how to stop the bolt from turning. Many resort to using pliers and screwdrivers and seriously scratch up their frame.

BTinNYC 

Framebuilders Supply?

Don wanna be welding on that galvanized too much or a-tall.

MudPie

You just need M8 hex head bolt? Try: https://www.mcmaster.com/products/sc...hread-size~m8/
Or grainger.com. There are Grainger outlets throughout and if you're lucky there's one near you.
All grades and lengths, packs of 25s, 50s...different materials, grades, fully or partially threaded, depending on length.

soyabean

I don't think I was clear.

I want to purchase the seatpost binder bolt only that has the lump in it.

There is a photo of it above.

I'm already taking plain M8 bolts and welding the lump to them.

I'm not looking for any sources for plain metric bolts.

I'm looking for any sources for M8 binder bolt only as pictured above.

MudPie

Sorry, I misunderstood and I missed the key feature under the bolt head.

JoeTBM 

So, you are looking for these, I know you said you wanted a quantity and this is for individual. Maybe a call to this LBS (BTW this is the LBS I used to go to when I lived on LI) is worth a shot. I believe the same bolt is also used for some quill stems to tighten the handlebars.

https://www.brandscycle.com/product/sunlite-hex-head-seat-binder-bolt-and-nut-324707-1.htm?variations=1396791,1396635&gad_source=1&gclid=Cj0KCQiAxOauBhCaARIsAEbUSQT_9sz_9deXTWcw0L6w7Fja aXggRtd681Bu5925U3HRUnXrE5XG0w8aApNPEALw_wcB

Here is another for $1.30 each

https://carsoncitybikeshop.com/seat-...UaAvA7EALw_wcB

Sunlite 51190

dedhed

Sunlite is a brand of J&B Importers,

​​​​​​https://www.jbi.bike/site/contact.php

FBinNY 

This used to be extremely common. It was used on virtually all Raleigh bikes for half a century, along with many other European bikes using similar seat lugs.

Find any shop that's more than 30 years old. Ask them where they buy them.

oldbobcat

That means you can buy it at just about any bicycle store. They might have to order it.

Andrew R Stewart 

JBI #51190 is what is being talked about. This is the common 8mm bolt with anti turn tab, but packaged with nut and washer as has been the case for decades if sourced from a bike industry supplier. For this specific bolt and in the quantity asked for I would charge about $1.50 each. These sell for around $2-$3 if out of the shop's on hand stock. I just checked the JBI quantity on hand among all their 11 warehouse locations and there's only about 80 total currently. The warehouse location, the shop I work with, has in stock and ready to ship to the shop has 8 available as example.

I won't do the math but I wonder if using a common cap screw and giving away the hex wrench too might be cheaper? Or if you're good with welding 100 bolts just add a short length of bar stock as a wing nut on the bolt head, again on a cheaply sourced common (and non zinc coated) bolt available in quantity packages for $0.25 each (or so). Andy

oldbobcat

Sometimes it just seems too difficult to walk into a bike shop and ask for something. I don't understand why.

Troul 

Usually if I run into a similar situation I go into my local hardware distributor/retailer & put an order together. It's rare to expect they'll have what I want on hand, but they have yet to let me down getting the order fulfilled.

Iride01 

Has to be exactly like the bolt you showed or will the fancier binder bolts that Framebuilder Supply has be good enough? https://framebuildersupply.com/colle...t-binder-bolts


Just asking, Seems like you addressed the person that got it wrong, but didn't address BTinNYC that seems to have suggested a reasonable substitute. They have the lug and come in different lengths.

icemilkcoffee 

If they are that mechanically clueless- the bigger risk is that they would try to turn the keyed bolt and end up chewing up the bolt hole. Or they'd take the bolt out, and then reinstall it backwards, and then chew up the side that doesn't have the keyed notch.

bboy314

+1 on J&B having these, I’ve sold many. If I were you I’d get an account, or find an LBS with one and order a bunch through them.

oldbobcat

J&B is strictly B2B. They want to support your local bike shop, not compete with it.

grumpus

Aren't they normally notched on both sides?

FBinNY 

No.

They're made for what was for decades the most common style of seat tube lug. The same basic design was used globally for decades.

The ears had a single notch used to key the bolt made for the job. BITD we bought these by the thousands from Eldi.

Duragrouch

I commend your weld fabrication of similar.

I recognize the bolt from my childhood cheap and vintage bikes, some of my bikes had that projection all the way across to the other side I think. But come to think of it, I don't have a single bike now with that feature, either the frame is female threaded or insert-nut on the left side into a hex hole for bolt entering on the right, or no bolt and they use a "turtleneck" top, either quick-release or with bolt.

Iride01 

I wonder if the OP found what they wanted.

rosefarts

My 5 steel bikes all have a threaded collar but so do I. Mostly I’m impressed that he fabbed up the bolt rather than just grabbed 2 wrenches.

wheelreason

You could "Cobalto" them with a rhinestone and some epoxie, and upcharge....

oldbobcat

If it was notched on both sides you wouldn't be able to turn the nut to tighten it.

FBinNY 

I think he meant both sides, not both ends.

79pmooney

No help to anybody here but fun - My Peugeot UO-8 that started my journey on road bikes in 1967 died on a car door 25 years later. The plain steel seatpin got tossed in a box. Then I realized I was getting tired of fussing with my Campy bolt which 1) was lousy with the brake cable hanger I used for my Mooney's cantis and 2) over time broke because of the poor fit with that hanger. "Duh! I've the right pin! Pulled it out, cut it to size and used it for the next 30 years. Now honorably retired.