First time wheel build and spoke length

anewman

I naively decided I should build myself some wheels, and duly bought a pair of 36h Mavic TN719 rims that were reduced at CRC. I'm planning to pair these with a Shimano XT DH-T785 dynamo front hub, and mostly so the rear is cosmetically similar an FH-M785. Being a relatively heavy rider, using disc brakes, and carrying a little luggage on commutes, my plan is to use DT Swiss Alpine III spokes, and to lace these up 3 cross, with 12mm brass nipples.

I have used a couple of spoke calculators and come up with the following....

Front: L 285.8 / 286.5 R
Rear: L 289.3 / 290.4 R

Having spent a while reading, it seems the agreed consensus is to round down, because running out of threads is more problematic (though the Sheldon Brown site suggests always rounding up). I am therefore planning to buy:
285 / 286 / 288 / 290

Are these likely to be ok? My main concern is rounding 289.3 down by 1.3mm to 288, as 289 are not available.

Many thanks in advance.

redvee

Rosebikes have odd length spokes, wether they have the ones you want is another matter.

anewman

redvee wrote:

Rosebikes have odd length spokes, wether they have the ones you want is another matter.

This is where I was looking at buying from. 289 is the one they don't have

redvee

If you buy them from Rose, count the spokes before you start building the wheels. I ordered 36 spokes from them, opened the box and got the spokes in the bag out and put them with the hub. Sat down to lace the wheel and did 16 spokes then looked at what I had left then realised they had only sent 20 spokes. I emailed them and the balance was sent out the same day.

desweller

1/2mm here or there is not going to matter. TBH, 1mm here or there is probably not going to be super critical.

The Rookie

Are you using the quoted ERD for the rims or have you measured it? many rims come out a long way off the quoted ERD (ref Roger Mussons excellent wheelpro book) and thus your spokes will be the wrong length....measure first, order later. My Friend only uses Mavic rims and they often come out upto 5mm out on ERD, making worrying about 1mm spoke length somewhat irrelevant!

For info Tarty Bikes do Sapim comp DB spokes very cheaply...where I got mine from, £17.50 for a set (no nipples, £20.50 with).

If you use the DT Swiss calculator it suggests which odd or even length spoke to use for you!

patrickf

Roger Musson says you can go 1mm either side but no more. Round up or down by that amount to give you the spokes you can get. His book is worth a read.

In your case ideal would be:

Front: L 286 / 287 R
Rear: L 289 / 290 R

But you could also go with:

Front: L 285 / 286 R
Rear: L 290 / 291 R

Why do you get different spoke lengths for a front wheel?

desweller

patrickf wrote:

Roger Musson says you can go 1mm either side but no more. Round up or down by that amount to give you the spokes you can get. His book is worth a read.

In your case ideal would be:

Front: L 286 / 287 R
Rear: L 289 / 290 R

But you could also go with:

Front: L 285 / 286 R
Rear: L 290 / 291 R

Why do you get different spoke lengths for a front wheel?

Different hub dimensions.

The Rookie

Are those spoke lengths assuming the ERD is quoted correctly? If so they are probably 2mm too long.

rrsodl

The Rookie wrote:

Are you using the quoted ERD for the rims or have you measured it? many rims come out a long way off the quoted ERD (ref Roger Mussons excellent wheelpro book) and thus your spokes will be the wrong length....measure first, order later. My Friend only uses Mavic rims and they often come out upto 5mm out on ERD, making worrying about 1mm spoke length somewhat irrelevant!

For info Tarty Bikes do Sapim comp DB spokes very cheaply...where I got mine from, £17.50 for a set (no nipples, £20.50 with).

If you use the DT Swiss calculator it suggests which odd or even length spoke to use for you!

I read with interest your comment on Tarty Bikes so I visited the website only to find out you cannot buy by length but by the size of wheel you are building ie 26" that is not what I was expecting, spokes don't come one length for all. Disappointed.

supersonic

286 front, 290 rear.

The Rookie

RRSODL wrote:

I read with interest your comment on Tarty Bikes so I visited the website only to find out you cannot buy by length but by the size of wheel you are building ie 26" that is not what I was expecting, spokes don't come one length for all. Disappointed.

Yes you can if you are smart enough to actually look at and read the pages, hey are bundled by wheel size on the display pages but give the lengths when you look and then you order by length. just read the page!
http://www.tartybikes.co.uk/26_inch_spo ... 6p239.html

Glad to have educated you and removed your disappointment all in one!

I was also smart enough to work out what length spoke I needed and then despite my bike being 32H ordering 36 spokes to get some spares for the same price!

MOD EDIT: I suggest you review the way you speak to fellow members asking for help in future.

rrsodl

The Rookie wrote:

RRSODL wrote:

I read with interest your comment on Tarty Bikes so I visited the website only to find out you cannot buy by length but by the size of wheel you are building ie 26" that is not what I was expecting, spokes don't come one length for all. Disappointed.

Yes you can if you are smart enough to actually look at and read the pages, hey are bundled by wheel size on the display pages but give the lengths when you look and then you order by length. just read the page!
http://www.tartybikes.co.uk/26_inch_spo ... 6p239.html

Glad to have educated you and removed your disappointment all in one!

I was also smart enough to work out what length spoke I needed and then despite my bike being 32H ordering 36 spokes to get some spares for the same price!

You know what they say about people blowing their own trumpet about how smart they think they are

Under the product information "Additional information" says

"If you know which lengths you need, please add this to the notes field when you check out.

If you are unsure what length spokes you need, then please write in the notes field which exact rim and hub you are using (brand, model, year if possible), whether the wheel is front or rear (or a pair if you have ordered 2 quantity of spokes), and number of spoke holes (28h/32h/36h). We will then work out the lengths for you - simple!"

Unless I'm going blind or you are smarter than my phone then I cannot see them listed by size like other websites. The problem with this method, besides being old fashion is that you don't know if they have in stock the sizes you want. What if they have for one side but not for the other? You wouldn't know until they tell you. I'd rather go to a site where I can order and be sure they have what I need.

I'm glad I'm not shopping for a pair of trousers or I'd have to tell them a bunch of my measurements

The Rookie

Going blind perhaps, possibly smarter than your phone, I don't know!
Second bullet point down on the page I linked to.
"Available in most common sizes for 26" wheels: we stock 252mm through to 268mm in 2mm increments"

(Bold is my emphasis)

Never said I was smart, just I read the pages first before blowing off at how 'disappointed' I am when the info was actually there all along.

That however is the end of my help, I've lead you to the water - twice.

rrsodl

Yeah I saw that before but if that is a link to a page where one can select the size to order, the browser on my phone doesn't see it as a link. I'll try that on my laptop later on. Having said that I'm looking for 700c spokes but it's good to know where to find spokes for 26" wheels for a future build.

The Rookie

No, you order and then state the lengths in the notes box on the page when checking out, it's not uncommon for ordering spokes to be like that for all but the largest shops.

Find the length you need using a calculator, the DT Swiss calculator is very nice, you may find 268mm is long enough, if you have larger flanged hubs or if (front) you radial spoke.