HillRider

As you sometime manage, there is some wisdom in your otherwise incoherent babble.

If the OP is willing to use brifters or barend shifters and just needs to fit a pair of cable housing stops over the bosses, he can do just what your recommend. Drill through both bosses and the both sides of downtube with a 3/16" bit. Run a long 10-32 or M5 bolt through both the cable stops and the frame. Thread a locknut over the end and file the excess smooth and flush.

I did just that to salvage an older Klein Al frame that had the downtube bosses held in place with a very thin double threaded rod was prone to strip and was a common problem with these bikes. The repair is now about 10 years old and working perfectly.

Grand Bois

As I explained before, a low end '74 Peugeot only has a shifter boss on the right side. The left side boss clamps on. The higher end models did not have bosses at all. The bolts for the original Simplex have the correct threads, of course. The bosses are a non-standard size and you may not be able to find anything that fits without some modification.

I use the single boss as a bell mount on my '74 PA10 fixie. I cut off the stud on the bell, drilled a proper sizes hole, cut the head off of a Simplex shifter bolt and silver soldered it in the hole.



This is the clamp on shifter for the left side. I don't agree that drilling straight through the tube is the solution to the problem. You need to find something that works with both the brazed on and clamp on boss. The shifters with the clamp are on eBay all the time. They'll work.

JRT

This thread -- M5x1.0 -- does, in fact, exist. I have these too. The question is exactly what size it is. I also used a M6x1 bolt as a thread gage and think that it *is* 1mm pitch.

I found this in Google:

https://www.icyclesusa.com/catalog/ti...rotor-bolt.htm

Ti is probably overkill and these are probably not long enough, but this is a size of thread that is used on cycles. And, I found a tap and die company that lists that size.

So, more searching might produce them.

dedhed

Maybe something like this might work.

https://littlemachineshop.com/product...ProductID=2616

tatfiend 

Per my Pocket Ref. book's metric tap and die information pre ISO French metric threads for 5mm were .90mm pitch. There were a number of different pitches used on metric fasteners of a given size, which varied by country, prior to ISO standardization. My Craftsman metric tap and die set is old enough so it has some French metric taps and dies.

Another example that might be run into is Japanese JIS Metric threads. Early Honda motorcycles from the 1960s used them and in most cases the threads were different pitch than ISO standard metric fasteners. They would most likely be found on pre bike boom Japanese bikes brought back by returning GIs. I remember that about the only places that had the JIS Metric fasteners were Honda motorcycle dealerships.

Per a conversation years ago with a German they had their own metric thread pitches too prior to adopting the ISO standard.

Grand Bois

You guessed right. Some Peugeot shifter bossed are 10-32.

JRT

Well, I have been to the hardware store with the bolts from my MB and I can report that they had an M5x0.9 Die ad it wouldn't fit. So they checked it with a thread gauge and yes it is 1.0 thread.

My suggestion is that rather than mutilate a vintage bicycle that you get an M6x1.0 bolt and an M5x1.0 hex die and chase the threads down to fit. Still have not obtained a die, but they do exist. I have seen them on the web for mail order.

tatfiend 

JRT;

Interesting. It would not surprise me if Peugeot used some proprietary thread pitches or even possibly German pre ISO pitches. After all Raleigh and Schwinn used proprietary sizes and threadings. The British even at one time had a series of bicycle industry threads used by almost no one else I have read. Matbe the French did too.

JohnDThompson 

Nobody's mentioned a helicoil yet. Drill out the old threads and pop in an M5 x 0.8 helicoil.

JRT

Well I ordered a die from Amazon and it isn't going to work to rethread M6 bolts. However, it is possible to get M5x0.8 bolts that are true bolts (that is: only partially threaded). I bought 2 50mm long ones and they have +/- 33mm with no thread. So, just cut off the threaded end and thread them with the die.

These appear to be available in hex head -- which would work with the Simplex shifter's slip on wing bolt conversions -- or standard Allen cap head. Unfortunately, they do not appear to be available with Allen button head. Actually, McMaster-Carr indicates that they might exist:

https://www.mcmaster.com search for item 92095A228

Look at the note in the drawing.

And I found them listed in stainless steel -- wouldn't want to by a box of stainless steel bolts though.

theacox

I ran into this same problem a couple of months ago on an childs bike from China. It was missing a nut from the wheel assembly that caused the wheel to shift when tightened.

No nut at Lowes, Home Depot, etc would thread.

Finally, while trying random loose nuts in the bottom of the specialty fastener hardware bin, I found a nut that worked!

Nothing in the bins matched it in look or size anywhere. I figure someone was looking for a matching screw and gave up and threw the nut in the bin.

Beats me, I out a loose tag on it and bought it!

Crazy
Tim

sliderule2

My 1974 Peugeot Simplex rear derailleur fastens to the frame with an M5x1.0x10mm bolt into a threaded spacer that positions it in the dropout. I snapped the bolt! You can't find/afford M5x1.0 fasteners! My fix was to chase the spacer with an M5x0.8 tap, use an M5x0.8X12mm bolt and back it up with a nut. In retrospect a better fix may have been to chase it with a 10-24 tap! My reasoning:

Major Diameter: M5x1.0=0.197"; M5x0.8=0.197"; 10-24=0.190".
Pitch Diameter: M5x1.0=?; M5x0.8=0.174"; 10-24=0.163".
Threads Per Inch: M5x1.0=25.4; M5x0.8=31.8; 10-24=24.

Next time!

FBinNY 

I didn't read all the posts, so sorry if this is a dup of n earlier suggestion.

First of all, back in the day, Simplex did use a M5x1 thread on the lever screws, and odds are that in some junk bin at an old "dirty fingernails" bike shop you'll find a set of clamp-on Simplex levers and can snag the screws.

Or you might try tapping for a US 10-24 screw which is close enough to have a decent chance of working. In fact you might not have to tap at all. Buy a heat treated 10-24 cap screw and oil it well and force it in by degrees, going just slightly past where it meets resistance, backing out, then forward a bit deeper until you've reached bottom. Then buy a pair of 10-24 screws of the right length.

M6x1 isn't a good option because then the screws will be too fat for the lever hardware. But a 5x1 helicoil might be if the boss has enough material. However, that's not going to be a cheap option whether you buy a kit or have someone else do the job.

One cheap and easy option is to drill through the boss and frame on both sides with a 5mm drill, then use a long screw that passes clea through with a nut on one end. Or a 5mm threaded rod with nuts at both bends.

If it were mine, I'd scrounge for old levers, try the 10-24 screws, then drill it through and use 5x.8 threaded rod and nuts, in that order.

Dan Burkhart 

I think you're on the right track, but I think 10x24 would be closer to m5x1
EDIT: Doh! Zombie thread, and I see others also suggested 10 24.

ksisler

SpinUp;
1) I checked my "go to" site for fasteners; KL Jack | Industrial Fasteners and Supplies - 1-866-471-3626 | SALES@KLJACK.COM (wide selections of Grade 5 and 8 as well as stainless and bronze) and indeed they don't have any M5x1.0 fasteners. They do have metric tape and die sets but there is not enough is info provided to show whether M5x1.0 is included. Could email them on their tools or to see if they might have a few 1.0's bolts lying around somewhere (not usual for them to have a few of many really odd things that are not listed on their public site).

2) Also checked Home Improvement Made Easy with New Lower Prices | Improve & Repair site for metric tap and die sets (they sell many sets) and was surprised to find that none of them included a M5x1.0. However several of them included both a M5-0.8 and a M5-0.9 tap/die pairs. I might draw the conclusion that you actually have a 0.9 instead of a 1.0. Might be worth taking one of your existing bolts into whatever type of store sells tools in Canada and see if by chance your item spins into a 0.9 die -- it could happen.

Hope that helps
/K

ksisler

https://www.icyclesusa.com/catalog/ti...rotor-bolt.htm

Link goes no where

Dan Burkhart 

Not surprising as the post you took the link from is over 5 years old.

fietsbob

Tried taking the bolt to an auto parts or industrial fastener shop..? may involve turning off the computer..

dstaudacher

icyclesusa link on archive.org's "Wayback Machine":
https://web.archive.org/web/20090620...rotor-bolt.htm

Racing Dan

How do you know? How did you figure that out?

Im betting its a standard metric thread. A M6 internal thread measures close to 5 mm with a vernier caliper.

JanMM

spinup started and posted in this thread in 2008. And was last active on BF in 2014. I wouldn’t expect a response from spinup.