Help needed on a wheel build.
04-02-24, 01:53 PM
#26
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Thank you for clearly, though possibly unintentionally, showing the issue with ERD data.
In your linked post are images showing ERD for a single wall and 2 double wall rims. They're inconsistent because the first has ERD to the nipple seat, and the other two to the nipple top.
Both are "correct" depending on how you define ERD, but I suggest you settle on one and synchronize the graphics accordingly.
In your linked post are images showing ERD for a single wall and 2 double wall rims. They're inconsistent because the first has ERD to the nipple seat, and the other two to the nipple top.
Both are "correct" depending on how you define ERD, but I suggest you settle on one and synchronize the graphics accordingly.
The consistent procedure is explained in the text, while those images are intended to be as clear (and simple) as possible to folks who have no idea what ERD is.
Iteration.
Relja
04-02-24, 03:49 PM
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And neither (referring to the picture 1 and picture 3) is 100% correct if you pay attention to where the ERD is marked on either.
The consistent procedure is explained in the text, while those images are intended to be as clear (and simple) as possible to folks who have no idea what ERD is.
Relja
The consistent procedure is explained in the text, while those images are intended to be as clear (and simple) as possible to folks who have no idea what ERD is.
Relja
My point was simply that there are two versions of ERD, a rim dimensional spec. and an input for spoke calculators.
Knowing that, and double checking helps prevent the all too common 4mm error the OP made.
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04-03-24, 07:31 AM
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Twist them together until they're the right length. Yes I have done this, no I wasn't proud of the result but it did work: how long they would have lasted I don't know, because the skinny 26" tyres I built the wheels for rode badly so I slung them in the corner and forgot about them.
04-03-24, 07:52 AM
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When wheels are such an important part of bikes, why would you not want to acquire the skill to make and fix them? So when for example you get a wheel with a bad hub, you can swap it out for the cost of nothing but your time, rather than buying a new wheel. Or when you want a certain rim with a particular hub you can just buy the bits and build a new pair of wheels to your exact requirements.
04-03-24, 12:19 PM
#30
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It's worth calculating the lengths of the spokes for the rear wheel (using a measured ERD) to see if the 'too short' front spokes are long enough for the drive side.
May not be, as the difference is only about 1 or 2 mm on the wheels I've built, it depends on the dish and what hubs you're using.
Otherwise keep them for another day.
Building wheels is time well spent, lots of exciting vintage hubs and rims out there on Ebay.
May not be, as the difference is only about 1 or 2 mm on the wheels I've built, it depends on the dish and what hubs you're using.
Otherwise keep them for another day.
Building wheels is time well spent, lots of exciting vintage hubs and rims out there on Ebay.
04-03-24, 03:12 PM
#31
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It's worth calculating the lengths of the spokes for the rear wheel (using a measured ERD) to see if the 'too short' front spokes are long enough for the drive side.
May not be, as the difference is only about 1 or 2 mm on the wheels I've built, it depends on the dish and what hubs you're using.
Otherwise keep them for another day.
Building wheels is time well spent, lots of exciting vintage hubs and rims out there on Ebay.
May not be, as the difference is only about 1 or 2 mm on the wheels I've built, it depends on the dish and what hubs you're using.
Otherwise keep them for another day.
Building wheels is time well spent, lots of exciting vintage hubs and rims out there on Ebay.
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04-03-24, 03:51 PM
#32
Senior Member
You want the rear DS set of spokes to be very close to the perfect length. The calculated end should be between the 'slot' and top of the head, or a little beyond after it 'stretches'. With modern hubs, the dishing is quite severe and the DS spokes will be very high tension. This is needed to still have the NDS tension at a reasonable level.
