ppg677

I've been trying to build/rebuild/ride a New-Old-Stock NOS Fiamme tubular rim. Fiamme Hard Silver.

I've built over a dozen wheels, so I'm not super experienced, but all of my other wheels have worked problem free with thousands of miles riding.

I can't go 100 miles before the Fiamme goes significantly out-of-true.

My first attempt re-used 30-year old spokes and was just a rim replacement using the trick of moving spokes over. It actually worked fine until I had a mishap where I put the derailleur into spokes. I then replaced the 9 damaged spokes and started having issues with losing true after 1-2 rides.

Then I bought all new double-butted spokes and completely re-laced/rebuilt the wheel. I was very careful. quarter turns while bringing up the tension. Several rounds of stress relieving. Linseed oil for thread treatment. I own a Park spoke tension meter and did my best for uniform spoke tension. Since its an older tubular, I kept drive-side tension around 90 Kgf, making non-drive-side around 55 Kgf IIRC. First 80-mile ride went fine. Next 20-mile ride and wheel went way out-of-true.

I'm about to give up on this rim. Just wondering if there is something obvious to look for.

And it seems that the NDS spokes are the ones that loose tension.

Perhaps I should try again and go to a higher tension, like 100 Kgf on drive side instead of ~90. With all my modern wheel builds, I shoot for around 120 Kgf.

79pmooney

Sounds like the NDS spokes need higher tension so they do not relax completely when unloaded while riding. Issue will be too high a drive side tension. Are you using a modern, high dish hub/cassette? If so, this may be more than that old rim was designed for. It would proably be far happier as a front rim or on a fix gear/single speed rear.

Ben

ppg677

Nope, vintage Record freewheel hub dished for 6-speed. I failed to mention I weigh 215 pounds :-)

I did rebuild the entire wheel using 16-gauge double butted spokes, with the idea that a lighter spoke is needed on the NDS to stay tight at lower spoke tension.

Drew Eckhardt 

You have too little tension for the spokes and rim you're using. 2.0/1.5mm spokes require less tension than 2.0/1.8, and 2.0/1.8 less than straight gauge. Your NOS rim is lighter, shallower, and therefore more flexible than what's currently popular which makes this a more likely problem.

1. Make sure you're using the right nipples. 15 gauge threads are smaller than 14 but the same pitch.

2. Make sure the wheel is dished correctly - if it's too far right the non-drive-side tension will be low.

3. Use Jobst Brandt's method of alternately adding tension and stress relieving (squeeze near parallel spokes on a side hard towards each other, or twist them about each other at the outer crossing using something softer like an old left crank, plastic screwdriver handle, or brass drift) until the wheel goes out of true in waves at which point you back off half a turn, true, and be-happy with the maximum viable tension for that rim.

My last Reflex clincher (~400g, about 30 less than an Open Pro) tensioned that way averaged 110kgf when I removed it for replacement. Your Fiamme might be good for less, but still more than 90kgf indicated.

Bill Kapaun

Do you mean 15/16, 14/16, 16/17 or**********

Typically, we want a minimum NDS tension of about 65kgf.
IF your DS spokes are too thin, you may start stretching them before you can achieve 65kgf on the NDS.

My typical rear wheel is 14/15 DS & 15/16 NDS.

Drew Eckhardt 

Nope.

Even 130kgf is far from the elastic limit on quality 17 gauge spokes like the ubiquitous (flattened not round) CX Rays.

ppg677

Thick part measures 2.0mm. Thin part measures 1.5mm. I believe that is 14/16. Used same spoke for NDS and DS.

jyl

I have had some recent experience with truing and building Fiamme Ergal tubular rims on vintage Record hubs. I pulled a spoke eyelet through one rim with excessive tension (apps 110 kgf). Those rims cannot tolerate high (modern) tension. After that I limited the DS to max 95 kgf kgf. With those hubs, which don't have much offset, the NDS tension will be acceptable, using thin double butted spokes. Be careful to avoid spoke windup, that may be the cause of your loosening spokes, more so than inadequate tension. I greased the nipple threads and the spoke eyelets, and followed the process of turning the nipple a little past the desired point, then backing it off, while holding the spoke in my fingers to feel for windup. The wheels have stayed true for many months including a couple of 100 mile rides. They don't stay as perfectly true as a modern rim (normally I use Mavic Open Pros) but stay true enough. I weigh 180-190 lb but, with these wheels especially, I "ride light".

https://www.bikeforums.net/bicycle-me...own-ergal.html

Bill Kapaun

14/17
14/16 would be 2.0/1.6mm

ppg677

Right, so if I'm understanding the Jobst Brandt's method described above, I don't want to do that to find the "max tension" a rim can support because I might end up pulling an eyelet through the rim, right?

jyl

I don't know, I've never used that method. When I was having trouble with the Ergal, FBinNY and others who are familiar with these old rims told me what max tension to use, and I just followed those instructions with good results.

Since nice Ergals aren't that easy to find, I'd err on the side of caution. I'd build the wheel, staying <95 kgf and avoiding windup, and see if it stays adequately true - and I wouldn't necessarily demand them to stay true to within +/- 1 mm . . .

In my sad experience, as you go to excessive tensions, you may see the rim inner surface (facing the hub) start to bulge, then bulge some more, then start to crack, then an eyelet pulls out. Or maybe it happens all at once, I'm not positive, my screw-up was a sample of one. Followed by a 2 month eBay search for a new/used set.

In general, even with modern rims, I am not convinced it adds anything to build wheels to the absolute maximum possible tension. If the tension is sufficient for the wheel to stay true and stiff with no spoke breakage, isn't that good enough? I used to build my Mavic Open Pros to >140 kgf because I thought more was better, but I don't do that any more.

Brian25

I rode on all sorts of sew ups going back to 1976. The most important fact that you are all missing is that that fiamme rim is under 300 grams, from my experience, that this rim was rated as an only front rim, the lightest rim I ever raced on was in the 330 gram or even heavier and I was only 135 lbs this guy is over 200 lbs. I do not care how will it is laced, or what spokes are used, it is simpily toooo light a rim. On a side note; One tr5ick i learned with wheel building is durring the tightening, to over tighten by an 1/8 th turn, and then back it off, to un twist the spoke. by doing this, you really reduce the amount of re truing after the first ride.

ppg677

The Fiamme Hard Silver are not as light as an Ergal. I believe we're talking about 350 grams. It might still be too light for my weight.

Drew Eckhardt 

It's probably too light. I bent my last ~400g Reflex clincher on a front wheel within months of riding it past 200 pounds although it stayed true for over a decade at 140-170.

If you really want you can use spokeprep on the NDS spokes (Wheelsmith invented it to limit warranty returns from heavier riders without running their truing robots slower or investing in expensive hand-labor getting proper tension) although forcing the issue is bad.

Wheels taco when you slacken the bottom spokes with a bump, the rim moves off-center, bump passes, and the wheel springs back from that position. Nipples unscrewing are an indication you're getting close to that point.

I started building my own wheels after a shop built me a set which never stayed true in back and folded on a small bump in front.

ppg677

I think I'm just going to switch to Mavic GP4s. I found a set for $30 (including Record hubs and skewers). I also have a set of Matrix ISO rims too that are probably tougher.