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Discussion Starter · #1 ·
Finally decided on rims for my Pista hubs, just sticking with Open Pros, which have served me well in the past.

Spoke calculator tells me 286.1 on the front, and then 287.3 left rear, 285.8 right rear.

Would you use 286.0 all around, or go 288.0 on the left rear? Thanks.
 

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I'd use 288mm for the left side, however are you sure about the lengths? Most fixed gear hubs are nearly symmetrical and use the same length left and right.

Judging by the spoke length I assume they're high-flange hubs?
 

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Discussion Starter · #3 ·
yup

Lab Worker said:
I'd use 288mm for the left side, however are you sure about the lengths? Most fixed gear hubs are nearly symmetrical and use the same length left and right.

Judging by the spoke length I assume they're high-flange hubs?
Yup, 1970's high flange pista. Not symmetrical. Center to left flange distance is 42 mm and 30 mm right. 602 mm ERD, 67.1 mm hole circle diameter.
 

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Fixed said:
Yup, 1970's high flange pista. Not symmetrical. Center to left flange distance is 42 mm and 30 mm right. 602 mm ERD, 67.1 mm hole circle diameter.
Thanks, I know the model you're referring to now.

A couple of things...have you measured the ERD? Most of the Open Pro's I've had lately have been 604mm ERD.

Using the measurements you gave (and assuming 12mm nipples and nothing funky) I calculate different lengths. I double checked with the DT calculator which gave these:
32x3 291.8 | 290.3
28x2 283.4 | 281.9
 

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Discussion Starter · #5 ·
36x3

Lab Worker said:
Thanks, I know the model you're referring to now.

A couple of things...have you measured the ERD? Most of the Open Pro's I've had lately have been 604mm ERD.

Using the measurements you gave (and assuming 12mm nipples and nothing funky) I calculate different lengths. I double checked with the DT calculator which gave these:
32x3 291.8 | 290.3
28x2 283.4 | 281.9
These are both 36 x 3. I used this calculator: http://www.wheelpro.co.uk/spokecalc/ ; I'll run it with 604 ERD; the 602 I found published in several places.

The DT calculator kept glitching on me.
 

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Discussion Starter · #6 ·
Lab Worker said:
Thanks, I know the model you're referring to now.

A couple of things...have you measured the ERD? Most of the Open Pro's I've had lately have been 604mm ERD.

Using the measurements you gave (and assuming 12mm nipples and nothing funky) I calculate different lengths. I double checked with the DT calculator which gave these:
32x3 291.8 | 290.3
28x2 283.4 | 281.9
Using 604 ERD, I get (3x) 287.1 front, 288.3 left rear and 286.8 right rear. Round up to next larger even sizes? Thanks.
 

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ohdee said:
I goofed originally and calc'd assuming 32 holes.

Your numbers look good. I'd go 288 front and rear NDS, 286 rear DS. That's just me though.
If you haven't (cant?) measure the ERD then I'd use 288 | 286 as this would let you get away with either 602 or 604mm. If you measured the ERD at 604 I'd probably use 288mm both sides.
 

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Discussion Starter · #9 ·
I screwed up big time

Lab Worker said:
If you haven't (cant?) measure the ERD then I'd use 288 | 286 as this would let you get away with either 602 or 604mm. If you measured the ERD at 604 I'd probably use 288mm both sides.
I can't figure out what's wrong. Finally got the spokes, the 288/286, and beginning with the drive side rear hub, the spokes were so short I could not even lace up one side. Something went very wrong. Of course, just had to have dipped all 72 spokes in spoke prep, so I'm sitting here with $75 worth of useless Revolution spokes.

Any ideas? Thanks.
 

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Fixed said:
I can't figure out what's wrong. Finally got the spokes, the 288/286, and beginning with the drive side rear hub, the spokes were so short I could not even lace up one side. Something went very wrong. Of course, just had to have dipped all 72 spokes in spoke prep, so I'm sitting here with $75 worth of useless Revolution spokes.
Any ideas? Thanks.
I have some spare spokes for my OpenPro/Campagnolo 1970 era large flange Pista hub/x3/36h track wheels and they are 296 and 293mm. So somehow your calcs are way off.

Dunno what you guys are doing wrong.
 

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Discussion Starter · #11 ·
Erd?

Mike T. said:
I have some spare spokes for my OpenPro/Campagnolo 1970 era large flange Pista hub/x3/36h track wheels and they are 296 and 293mm. So somehow your calcs are way off.

Dunno what you guys are doing wrong.
Maybe the ERD is off. I did not actually measure, but used published specs, as I order spokes along with the rims. Suppose I should measure now.

Do you know what you use for ERD? Thanks.
 

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Fixed said:
Maybe the ERD is off. I did not actually measure, but used published specs, as I order spokes along with the rims. Suppose I should measure now.
I've helped people with wheelbuilding for decades and always promote self measuring of the parts. Those who provide incorrect specs are never held accountable for their misinformation. Even the makers and marketers of wheel parts sometimes get it wrong, never mind well-meaning people on forums.

I feel your pain.

And by the way - please don't use the measurements I gave for my wheels' spokes in my previous post. It could be that I mislabeled the spare spokes.
 

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Did you get the number of crosses right when lacing? The spoke lengths you calc'd were for 3x, if you are trying to lace 4x then the spoke will be too short.

I went back through the calcs with my own spreadsheet and with the numbers you posted and everyones best guess at an Open Pro's ERD - those lengths make sense. :confused:
 

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Discussion Starter · #15 ·
not that far

Lab Worker said:
Did you get the number of crosses right when lacing? The spoke lengths you calc'd were for 3x, if you are trying to lace 4x then the spoke will be too short.

I went back through the calcs with my own spreadsheet and with the numbers you posted and everyones best guess at an Open Pro's ERD - those lengths make sense. :confused:
Didn't even get that far. I could not even lace the trailing spokes on one side, so this was zero cross, er radial. Could not even get all 9 spokes on. Bizarre. Maybe I should check the lengths of the spokes they sent me, too. I've build several wheel sets before, I'm not completely new to this, and it just doesn't add up.
 
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