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Spoke threads exposed on new wheel - Safe?
Last night, I built a new rear wheel for cross riding using a Record
36 hole hubs, a Ritchey OCR Comp rim (called Trekking on web site) and DT 14/15 spokes. In doing the research, I noticed that Ritchey's web site gave the ERD as 596 mm whereas Damon Rinard's Spocalc gave it as 605 mm. Perhaps Ritchey has redesigned the rims? At any rate, I called Ritchey and the rep talked to a wheel builder who gave the ERD 599. Hmm... Right between the two values... I plugged the 599 value in Spocalc and built the wheel using 290's on the left and 288's on the right. At this point, I've tensioned them to 70 kg on the left and 115 on the right. On inspection, I noticed that the left side as 2-3 threads exposed all around whereas the right side has 5-6 threads exposed. I'm comcerned that the spokes are too short and I don't have enough threads embedded in the brass nipples. Is this wheel safe or should I rebuild it with longer spokes? Thx, Dave |
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Spoke threads exposed on new wheel - Safe?
"Dave S" wrote in message
om... Last night, I built a new rear wheel for cross riding using a Record 36 hole hubs, a Ritchey OCR Comp rim (called Trekking on web site) and DT 14/15 spokes. On inspection, I noticed that the left side as 2-3 threads exposed all around whereas the right side has 5-6 threads exposed. I'm comcerned that the spokes are too short and I don't have enough threads embedded in the brass nipples. Is this wheel safe or should I rebuild it with longer spokes? Rebuild it. 1 or 2 is ok in a pinch. 5 or 6 is NFG. Especially on the drive side. Cheers, Scott.. |
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Spoke threads exposed on new wheel - Safe?
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Spoke threads exposed on new wheel - Safe?
Dave S wrote:
: Last night, I built a new rear wheel for cross riding using a Record : 36 hole hubs, a Ritchey OCR Comp rim (called Trekking on web site) and : DT 14/15 spokes. : In doing the research, I noticed that Ritchey's web site gave the ERD : as 596 mm whereas Damon Rinard's Spocalc gave it as 605 mm. Perhaps : Ritchey has redesigned the rims? : At any rate, I called Ritchey and the rep talked to a wheel builder : who gave the ERD 599. Hmm... Right between the two values... : I plugged the 599 value in Spocalc and built the wheel using 290's on : the left and 288's on the right. At this point, I've tensioned them : to 70 kg on the left and 115 on the right. : On inspection, I noticed that the left side as 2-3 threads exposed all : around whereas the right side has 5-6 threads exposed. I'm comcerned : that the spokes are too short and I don't have enough threads embedded : in the brass nipples. I also had less than ideal results with an OCR rim. I just built a wheel with a Ritchey Aero Road OCR rim that spocalc lists as 606mm, and I ended up with about 1mm protruding out the back end of the nipples. Looking at spocalc again, it has in parentheses "ERD is nipple contact dia + 3mm for nipples". Does that comment mean I needed to make some adjustment to the numbers before plugging them into the calculator? I know I had the right hub dimensions, because I verified them calipers. Anyone have a good technique for measuring ERD? - mark |
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Spoke threads exposed on new wheel - Safe?
Dave S wrote:
Last night, I built a new rear wheel for cross riding using a Record 36 hole hubs, a Ritchey OCR Comp rim (called Trekking on web site) and DT 14/15 spokes. In doing the research, I noticed that Ritchey's web site gave the ERD as 596 mm whereas Damon Rinard's Spocalc gave it as 605 mm. Perhaps Ritchey has redesigned the rims? At any rate, I called Ritchey and the rep talked to a wheel builder who gave the ERD 599. Hmm... Right between the two values... I plugged the 599 value in Spocalc and built the wheel using 290's on the left and 288's on the right. At this point, I've tensioned them to 70 kg on the left and 115 on the right. On inspection, I noticed that the left side as 2-3 threads exposed all around whereas the right side has 5-6 threads exposed. I'm comcerned that the spokes are too short and I don't have enough threads embedded in the brass nipples. Is this wheel safe or should I rebuild it with longer spokes? The 2mm showing on the left is trivial but the right needs to be redone. Just curious but what lengths did you use? Normally rights are 2mm shorter than lefts. -- Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971 |
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Spoke threads exposed on new wheel - Safe?
It is a pain to get the wheel built and find out the spokes aren't the
correct length. The Ritchey PRO Trekker Girders I have measure ERD 605 mm. I used 294 mm right and 296 mm left. The spoke length came in fine on my Shimano XTR and DURA ACE hubs. Mine are 32 spoke 3X. Where did you find the 36 hole version? -- David Ornee, Western Springs, IL USA -------------------------- Posted via cyclingforums.com http://www.cyclingforums.com |
#7
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Spoke threads exposed on new wheel - Safe?
Alex Rodriguez wrote:
In article , says... Last night, I built a new rear wheel for cross riding using a Record 36 hole hubs, a Ritchey OCR Comp rim (called Trekking on web site) and DT 14/15 spokes. In doing the research, I noticed that Ritchey's web site gave the ERD as 596 mm whereas Damon Rinard's Spocalc gave it as 605 mm. Perhaps Ritchey has redesigned the rims? At any rate, I called Ritchey and the rep talked to a wheel builder who gave the ERD 599. Hmm... Right between the two values... I plugged the 599 value in Spocalc and built the wheel using 290's on the left and 288's on the right. At this point, I've tensioned them to 70 kg on the left and 115 on the right. On inspection, I noticed that the left side as 2-3 threads exposed all around whereas the right side has 5-6 threads exposed. I'm comcerned that the spokes are too short and I don't have enough threads embedded in the brass nipples. Is this wheel safe or should I rebuild it with longer spokes? I would rebuild with the proper length spoke. I sounds like your spokes are too short by a few mm. If you look at your spoke nipples you can see that they are not threaded all the way. About half the nipple is unthreaded. So if you can see exposed threads, there are more unexposed threads that are not engaging the nipple. --------------- Alex I agree with Alex. On the Spoke Calc site there is a way to measure ERD: Effective Rim Diameter (ERD) is the diameter on which you want the ends of the spokes to lie. Most people prefer it near the end of the spoke nipple. If you want to measure your own rim (recommended, just to be sure), then follow these instructions: Insert two old spokes into holes exactly opposite each other on the rim. Count holes to be sure. Screw some nipples onto the spokes. Pull them tight and measure dimension A in the figure (the diameter to the edge of the nipples, where the spokes dissapears into them). Do this at several spots around the rim and average the measurements. Measure the length of a nipple (dimension B in the figure) and add it twice (once for each nipple). The result is Effective Rim Diameter (ERD). Thus, ERD = A + 2B. Effective Rim Diameter (ERD) is the dimension you type into the spreadsheet for "ERD, effective rim diameter". Of all the dimensions you actually might measure, ERD is the most critical dimension affecting spoke length, so it makes sense to measure it a few times at different places around the rim. Always count to make sure you use spoke holes that are actually opposite each other! It is a pain to get the wheel built and find out the spokes aren't the correct length. The Ritchey PRO Trekker Girders I have measure ERD 605 mm. I used 294 mm right and 296 mm left. The spoke length came in fine on my Shimano XTR and DURA ACE hubs. -- David Ornee, Western Springs, IL USA David Ornee, Western Springs, IL USA -------------------------- Posted via cyclingforums.com http://www.cyclingforums.com |
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Spoke threads exposed on new wheel - Safe?
daveornee wrote:
I agree with Alex. On the Spoke Calc site there is a way to measure ERD: Effective Rim Diameter (ERD) is the diameter on which you want the ends of the spokes to lie. Most people prefer it near the end of the spoke nipple. If you want to measure your own rim (recommended, just to be sure), then follow these instructions: The OP has the advantage of an easy of way of calculating what size spokes to use for his rebuild: whatever size he used + the length of exposed thread! --Josh |
#9
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Spoke threads exposed on new wheel - Safe?
Josh Gatts wrote in message om...
daveornee wrote: I agree with Alex. On the Spoke Calc site there is a way to measure ERD: Effective Rim Diameter (ERD) is the diameter on which you want the ends of the spokes to lie. Most people prefer it near the end of the spoke nipple. If you want to measure your own rim (recommended, just to be sure), then follow these instructions: The OP has the advantage of an easy of way of calculating what size spokes to use for his rebuild: whatever size he used + the length of exposed thread! --Josh Dear Josh, You practical devil! Even if there are objections that I can't imagine, I admire your approach. You probably know the apocryphal story of Edison asking a college graduate who wanted to work in his lab to determine the volume of an empty glass light bulb. After the slide-rule expert finished laboriously measuring curves and calculating an approximate answer, Edison taught him a practical lesson by filling the bulb with water, pouring the water into a graduated cylinder, and announcing the exact volume. Thanks, Carl Fogel |
#10
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Spoke threads exposed on new wheel - Safe?
On inspection, I noticed that the left side as 2-3 threads exposed all around whereas the right side has 5-6 threads exposed. I'm comcerned that the spokes are too short and I don't have enough threads embedded in the brass nipples. BRBR They are too short. You could use 16mm nipps tho, which may fix the problem. Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302 (303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene" |
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