Hi All,

I'm replacing the steel hardware on my Ritchey stem with stainless steel. I can find the bolts no problem but am having the devil's own time finding M6 & M5 washers with a small enough outside diameter to fit in the wells.

Does anyone have any good references for these? I've tried pro-bolt-usa, and a couple of others with no luck.

Thanks!

Try Bolt Depot - stainless metric washers.

I have replaced rusted hardware on a few stems with stainless hardware and run into the same problem with new SS washers having an O.D. too large to fit in the recesses. While the OEM 5mm and 6mm bolts have standard threads, the washers under the heads are non-standard and essentially the same size as the bolt head.

I don't think you will find a retail source for these odd washers, and the easiest solution is to make your own.

Take an old bolt, slip a washer on it, and lock it in place under the head with a nut. This will give you a little jig to hold the washer while you modify it, and a guide to the size of it.

Take a file or grinder to the washer and reduce the diameter until it fits the stem recess.

It's interesting that stainless steel split lock washers have a smaller OD. Would these work as well as a flat washer. They'd certainly be easier to get. I might go that route.

Split washers with a little modification would probably be fine.

First, I'd bend the split ends to take the "spring" out of the washer so it lies flat, and then I'd give each side of the washer a couple of light strokes with a file or a few light taps with a hammer.

Typically, the split ends have an edge on them that is a bit thicker than the washer, and the edges tends to bite into the adjoining parts that the washer bears on, which is a good thing for a lock washer. For a flat washer, you don't want that, so flatten the edges of the split.

Offhand, I don't know of a close inch alternative for 6mm washers, but 5mm screws are extremely close to a #8 machine screw. So you can save dough and get better availability by shopping for #8 stainless washers which are readily available.

head to the marine supply hardware shop.

exposure to sea conditions demands stainless hardware.

Yacht service , for the non commercial sailor.

metric is world standard, though US fails to go along.

The thing is that there is a very good chance of finding the washer you need at a bigger Ace hardware or Automtive store that stocks a large selection of individial nuts bolts and washers, you just might need to take the bolt and part in and try a couple dozen washers till you find one that works. Just today I spent 45 minutes finding and buying a single 25 cent washer for a RD I'm rebuilding.

Right idea but wrong size number. An M5x.8 bolt is very close in size to a #10x32 machine screw.

Fastnal or Grainger local locations

I few of the posters here seem to be missing the point. 6mm SS washers are very common and blacksquid is not talking about acquiring a standard 6mm ss washer. The problem is finding a ss 6mm thin walled washer; one that will fit into the recesses in stems. I have bought numerous fasteners from Bolt Depot and while they are a great place to do business with, they do not carry thin walled washers and I've yet found anyplace that does. I have actually stooped to drilling out washers when I had no other choice; if your lucky you will get a good one every 2 or 3rd try

Went over to West Marine & picked up some SS split lock washers & modified according to Just Riding. Seems to work fine. The problem, as onespeedbiker nailed it, is the OD of a metric #5/#6 doesn't fit in the well of my stem.

Out of curiosity, I pulled some bolts on 4 stems. On two of the stems, a Ritchey and a Profile Design, I was surprised to find out that the bolts used were 7mm x 1.0mm. This is an unusual size; try googling it to find a source. Most likely, made to order for the OEM like most of these stem bolts seem to be.

The other two stems used 6mm bolts. One of them had a reduced diameter head (and a correspondingly small recess), and the flat washers under both of them were a reduced diameter. Measurements below.

For comparison, a standard 6mm bolt has a head diameter of approx. 9.9mm and a 6mm flat washer has an outside diameter (OD) of about 11.7mm. A 5mm flat washer is about 9.7mm OD, and 5 and 6mm split washers are about 8.8 and 11.2mm respectively.

Bolt 1:
head dia.: 9.0mm
washer OD: 9.3mm
stem recess: 9.4mm

Bolt 2:
head dia.: 9.9mm
washer OD: 10.1mm
stem recess: 10.3mm

I think the conclusion is don't expect to find drop in replacement hardware for most stems. At least be prepared to get your calipers out and check.

If you're lucky, the stem uses 6mm bolts and has room for the head. Then maybe you only need to deal with the washer. Other than that, I guess its firing up the file and grinder or searching the LBSs and spare parts bins.

I'd start by contacting Ritchey. They might have what you need.

www.mcmaster.com -- McMaster Carr Industrial Supply. Amazing selection, no minimum order.

Washers the same diameter as the bolt head are a standard industrial item.

Thanks for the link to McMaster Carr, but if they carry, say, 6mm SS flat washers with the same OD as the head of a socket head cap screw, I can't find them. If you know where they are, can you post a link?

In the small sample of 4 bolts I checked, 2 of them were 7mm, and one of the 6mm had a reduced head diameter. The flat washers used were all non-standard.

For me, the lesson from what seemed like a simple question from the OP is that much, if not most, of stem hardware is non-standard in some respect. Judging by what I found, trying to replace OEM hardware with off the shelf SS hardware is probably not going to be straight forward.

I think these might do the trick:
On this page:
https://www.mcmaster.com/#round-shims/=fpt9sq
go to "Shims for Lengthening Screw Shoulders—Metric"

https://www.mcmaster.com/#round-shims/=fpw7pt - Shims for Shortening Screw Shoulders, Metric

I suspect for 7mm you can find a near-equivalent in SAE, but I haven't actually looked. If you know the dimensions, use the left tab to sort by OD and ID.

Few bike parts are made in such large volumes that they'd actually use custom washers for a simple cap screw, but they may easily be using a less common standard. That's the wonderful thing about standards, there are so many to choose from!

If you own a bench grinder it's very easy to reduce the OD of stainless washers. Slip them over a screw, or Philips screwdriver shank and hold it gently against the spinning grinding wheel. Angle the axis slightly so the wheel spins the washer, while grinding the OD. Don't let the washer stall, or you'll grind a flat spot. It takes a bit of touch to get a nice spin grinding action, so your first washer may only be practice, but the next and all that follow will be spot on.

Chuck up the bolt and nut holding a stack of washers,
in the drill and run the drill counter rotating,
against the bench grinder.

Or, if you have a variable speed drill-motor you can secure, some how,
then while the piece rotates you can use a file, to reduce the OD.

Not quite. If you look at the metric shims for a 6mm ID the OD is still 12mm. Too big for most stem wells I think. I'm beginning to believe that just riding is correct. I used split lock washers and I'm happy with it so I just won't waste my time looking for those pesky flat washers.

It turns out that a 5mm flat washer is a pretty good match for the dia. of a stock 6mm bolt head. The ID is about 5.3mm, so it needs to be opened up a bit. I used a small grinding bit in a dremel tool to try one.

Of course if your stem uses a bolt with a reduced head diameter, then you'd probably need to reduce the washer OD also. FB and fietsbob had some good suggestions on how to do that.

I don't have any 4mm flat washers, but looking at the specs, it looks like it is pretty close to the dia. of a 5mm bolt head.

Looking around, I noticed that Bike Tools Etc carries some 7mm bolts, not stainless, specifically for stems. That's the only source I've seen for any kind of 7mm bolts.
https://www.biketoolsetc.com/index.cg...em_id=US-CS725

It turns out that a 5mm flat washer is a pretty good match for the dia. of a stock 6mm bolt head. The ID is about 5.3mm, so it needs to be opened up a bit. I used a small grinding bit in a dremel tool to try one.

Of course if your stem uses a bolt with a reduced head diameter, then you'd probably need to reduce the washer OD also. FB and fietsbob had some good suggestions on how to do that.

I don't have any 4mm flat washers, but looking at the specs, it looks like it is pretty close to the dia. of a 5mm bolt head.

Looking around, I noticed that Bike Tools Etc carries some 7mm bolts, not stainless, specifically for stems. That's the only source I've seen for any kind of 7mm bolts.
https://www.biketoolsetc.com/index.cg...em_id=US-CS725

Actually, they state 9.78 as the OD for in the "Shims for Shortening Screw Shoulders—Metric" list.

Mr. Squid-

McMaster has some washers for socket head cap screws, these are generally made to fit into a counterbore for a cap screw, (these are sometimes referred to as "hi collar" lock washers). Their stk #91111A124 is a stainless steel split lock washer for a M5 screw, the washer ID = 5.4mm, the washer OD = 8.8mm, and the thickness = 1.5mm. A standard M5 socket head screw should have a head diameter of 8.5mm so this washer is .3mm larger than the head, hopefully the counter bore for screw has that much clearance. by the way a package of 100 pcs of the aforementioned washers will set you back $2.90.

take care
bernie