Bicycle Mechanics - Spoke length: does 1 or 2mm make a difference?

Typing that question makes me feel dumb, but I've been wondering now for some time, so please put me out of my misery! I've searched the forums and can't find this topic, but apologies if it's been written about a million times already.

I've built a few wheels now, and am pretty comfortable with it, but have just bought some new Record hubs that I wanna build up with Ambrosia Excellight rims – so basically I don't wanna muck things up because they're expensive.

A mechanic friend of mine told me that you didn't really need two different spoke lengths for the rear wheel, as I had been told. In fact, he claims to often build the front and rear wheels with the same length spokes (he showed me a set of some retro Campy record hubs he'd just built up that he said had the same length front, rear [drive and non-drive]).

The reason this came up was because the LBS didn't have the lengths I need for the rear, or rather, that had the longer length but not the shorter. They seemed to think it would be no problem either, which got me thinking: does 1 or 2mm really make a difference?

I'd really appreciate some first-hand knowledge from an experienced wheel-builder.

It can...keyword = can.

With a 10mm nipple - 1-2mm can mean the difference between thread showing on the barrel end or not...

With a 12mm nipple - it can mean the difference between running out of threads or not...

With a 16mm nipple it can mean the difference between obtaining tension at the last thread - or not engaging the head of the nipple enough.

http://www.youtube.com/watch?v=gCXFKN9JvCQ&context=C31932c8ADOEgsToPDskLaenuUwwH7Boe2oBRcEd-L

Here's a video of nipple and thread behavior...just to get started...

Sure it can be done - but plan it out so that the spoke length used represents the average of the low and high aiming point for the nipple used.

I.e., if the spoke lengths are 299 and 297 - and the aim is for a thread or so past the flat of the nipple - then 298 would probably be the spoke length to use.

=8-)

Also, you really should encourage that LBS to get a spoke machine. If they give you the, "It's too expensive and we can't justify the cost..." line, there are quite a few here on BF who will tell you that spoke machines pay for themselves 10X over...

=8-)

+1

If you're 1mm away from the ideal spoke length, no it will not matter. 2mm away from the lower or upper limit can mean a wheel that cannot be built properly. Basically, you're building wheels from scratch so you might as well get the correct spoke lengths.



he claims to often build the front and rear wheels with the same length spokes (he showed me a set of some retro Campy record hubs he'd just built up that he said had the same length front, rear [drive and non-drive]).

This only makes sense if both hubs have the same dimensions, especially in the old days of high flange hubs front and rear. Yes it is possible but this is REALLY bad advice because in many cases it's not true. Again, just get the correct spoke length. There's no reason not to.

+1

If you're 1mm away from the ideal spoke length, no it will not matter. 2mm away from the lower or upper limit can mean a wheel that cannot be built properly. Basically, you're building wheels from scratch so you might as well get the correct spoke lengths.



This only makes sense if both hubs have the same dimensions, especially in the old days of high flange hubs front and rear. Yes it is possible but this is REALLY bad advice because in many cases it's not true. Again, just get the correct spoke length. There's no reason not to.

That was kinda the point: I can't get the exact length! The service here in Italy might not be up to what many might expect, and it's not uncommon to be given what they think you should have, rather than what you've asked for.

Thanks for the advice though guys. To say the builder here advised me to use the same length would be harsh on him, he merely said that it can be done without any adverse results. Watching that video and hearing what you have to say, I understand the limits a little better. I might try order online, but the last time I ordered spokes online it ended in disaster (they were something like 270mm long, instead of the 290 I needed ...).

So, the calculator at lenni.info says:

Hub: Campagnolo Record 2007+ Rear, rear
Rim: Ambrosio Excellight S.S.C.
Number of spokes: 32
Crosses: 3
Spoke length left: 293.2
Spoke length right: 291.2

If, the LBS doesn't have 293 and 291, is it safe enough to go with 292 all round, or better to risk ordering online again?

(thanks again)

Also, you really should encourage that LBS to get a spoke machine. If they give you the, "It's too expensive and we can't justify the cost..." line, there are quite a few here on BF who will tell you that spoke machines pay for themselves 10X over...

=8-)

IF.. one builds lots of wheels. I'd suggest in most bikes shops.. just the labor to cut and re-thread is a looser $$. IF.. they have a employee half competent in building wheels.. that is.

IF.. you ERD figures put the spoke end at the very top of the nipple.. IMO two short works. Again.. IF.. the threads cover... and depending on that thread length on the spokes. No it isn't perfect... but with firm spoke tension and the spoke end up past the rim thickness.. for me this condition has been functional with no problems.

Well, in some cases it's OK, but for a quality build, I'd just get the right size, rounded down, for a new build. I round down because I hate to run out of threads. It's also best to actually measure your ERD on the rim since the published specs may not match the rim you actually buy.

That being said, I have built wheels with Shimano front and rear hubs using the same length spoke for front and rear- in my case the front hub laced 2-cross took a 295 mm spoke, the drive side rear 3X was 294 and the non-drive side rear was 296. I bought 295 for all, and mashed the threading on the drive side rear (not generally recommended). The wheel is fine, but it was for a beater wheel I don't expect much from.

I've used spokes off by a couple/few mm a bunch of times and it worked out. But I was usually just reusing spokes to be cheap. If I had nice parts like you do and a clean slate, I'd put a little more effort into getting the properly sized spokes.

Typing that question makes me feel dumb, but I've been wondering now for some time, so please put me out of my misery! I've searched the forums and can't find this topic, but apologies if it's been written about a million times already.


Yes.

On a DT 12mm nipple with 8mm of thread measured to nipple end and DT spoke with 9mm of thread there's exactly 2mm between the bottom of the slot and the spoke reaching the end of it's threads.

If you use alloy nipples and the spokes end below the rim they can break (although brass spokes give you more latitude).

Finally rims vary in ERD, sometimes significantly. If your spokes end at the top of the nipples and the next rim is a bit past 2mm smaller the spokes will bottom.



The reason this came up was because the LBS didn't have the lengths I need for the rear, or rather, that had the longer length but not the shorter. They seemed to think it would be no problem either, which got me thinking: does 1 or 2mm really make a difference?
Sometimes.

If you're using brass nipples, the drive side end up at the end of the nipples, and the non-drive side spokes end 1mm below the slot you'll be fine.

That was kinda the point: I can't get the exact length! The service here in Italy might not be up to what many might expect, and it's not uncommon to be given what they think you should have, rather than what you've asked for.

Thanks for the advice though guys. To say the builder here advised me to use the same length would be harsh on him, he merely said that it can be done without any adverse results. Watching that video and hearing what you have to say, I understand the limits a little better. I might try order online, but the last time I ordered spokes online it ended in disaster (they were something like 270mm long, instead of the 290 I needed ...).

So, the calculator at lenni.info says:

Hub: Campagnolo Record 2007+ Rear, rear
Rim: Ambrosio Excellight S.S.C.
Number of spokes: 32
Crosses: 3
Spoke length left: 293.2
Spoke length right: 291.2

If, the LBS doesn't have 293 and 291, is it safe enough to go with 292 all round, or better to risk ordering online again?

(thanks again)

I wouldn't use a calculator with a database since there can be a 4mm difference between published numbers (there isn't a standard for aiming for the slot or nipple end) and actual which is the difference between a perfect wheel and one that doesn't build because you run out of thread or break nipples.

It depends on how the actual rims you have measure (at at least two points) when you thread a pair of spokes into the nipples you plan on using to the slots (or ends if that's your goal) and add twice that spoke length to the measurement across the elbows with your dial calipers.

It also depends on what spokes you're using - 2.0/1.5 spokes stretch nearly 1mm on the drive side and half that on the non-drive side.

I've gotten cocky before and eyeballed smoke lengths- I had a stock of spokes with maybe 20mm of threads for a while. Usually it worked out, but when it didn't it was a pain in the backside to file/dremel down the nub of spoke coming through the nipple.

It's not a deal breaker if you have enough thread, but if you have single wall rims or grossly miscalculated, be ready to file/cut.

It's not a deal breaker if you have enough thread, but if you have single wall rims or grossly miscalculated, be ready to file/cut.

Take your dremel with a stone bit head and run them off.. takes seconds. Been there on a few beater builds.

Take your dremel with a stone bit head and run them off.. takes seconds. Been there on a few beater builds.

Huh, thought I put that in there. Exactly what I've done.

A mechanic friend of mine told me that you didn't really need two different spoke lengths for the rear wheel, as I had been told. In fact, he claims to often build the front and rear wheels with the same length spokes (he showed me a set of some retro Campy record hubs he'd just built up that he said had the same length front, rear [drive and non-drive]).

With "retro" wheels the difference between the DS and NDS rear spokes is not as great as it is with modern 8, 9, 10, and 11-speed rear hubs because the DS flange offset is not as great. This also means that the spoke tension differential is not a great. If using long spokes the greatest risk is running out of threads "bottoming out" before reaching sufficient tension. When this happens your options are to replace the DS spokes or cut more threads, or lower the NDS spoke tension to a dangerous level in order to center the rim. I've had custom built wheels as well as machine built wheels bottom out the DS nipples because the spokes were too long. When ordering spokes I always round down from the calculated lengths and reduce an extra 1mm on the DS rear.

Cutting the ends off of spokes is not a problem, running out of threads is.

Go with the 292's. you will be ok. The perfect build has the tension high, the wheels true and the spoke ends even with the end of the nipples. I rarely build the perfect wheel and they last just fine.
I've built wheels for 225 and up rides with no problems. One with the power tap required a heavier rim. He kept cracking the Open Pro rims and the power tap doesn't come in a 36 hole hub.

I wouldn't use a calculator with a database since there can be a 4mm difference between published numbers (there isn't a standard for aiming for the slot or nipple end) which is the difference between a perfect wheel and one that doesn't build because you run out of thread or break nipples.

It depends on how the actual rims you have measure (at at least two points) when you thread a pair of spokes into the nipples you plan on using to the slots and add twice that spoke length to the measurement across the nipples with your dial calipers.

It also depends on what spokes you're using - 2.0/1.5 spokes stretch nearly 1mm on the drive side and half that on the non-drive side.

I didn't know that about the butted spokes, and I hadn't thought about the standard, so they're certainly two interesting points to consider.

I measure the same way you do (I even glue in the spokes so they don't move) and the ERD on the lenni calculator has always been the same as my measurement in the past. I haven't measured the Excellights myself, but a few online sources have the ERD as the same (600). The guy in the shop has a book with rim ERDs and the correct spoke/nipple combos and he still insisted I'd be ok ... but now I'm more unsure than ever!

I guess I could try to roll the online dice again ...

I didn't know that about the butted spokes, and I hadn't thought about the standard, so they're certainly two interesting points to consider.

I measure the same way you do (I even glue in the spokes so they don't move) and the ERD on the lenni calculator has always been the same as my measurement in the past. I haven't measured the Excellights myself, but a few online sources have the ERD as the same (600). The guy in the shop has a book with rim ERDs and the correct spoke/nipple combos and he still insisted I'd be ok ... but now I'm more unsure than ever!

I guess I could try to roll the online dice again ...

Unless the ERD includes a note as to the nipple type and size used - and the aiming point in the nipple - you can't trust the ERD.

You need a reference so you can determine what lies in the middle...for this particular task at hand...

=8-)

That was kinda the point: I can't get the exact length! The service here in Italy might not be up to what many might expect, and it's not uncommon to be given what they think you should have, rather than what you've asked for.

I've ordered from this guy a few times with no issues:

http://www.ebay.com/sch/childhood_dreams/m.html?_dmd=1&_ipg=50&_sop=15&_rdc=1

He says he ships internationally, but it might take a while. He will cut & thread spokes to whatever length you want.

DANS Comp sells Sapin Stainless 2.0's for one great price... shipping is very reasonable too. Every order I have made with them goes out that same day. Any length you want too. Sapin Strongs also.. not listed in their catalog.. just tell the order clerk you want them. Half a buck for them...:thumb:
http://www.danscomp.com/products/435905/Sapim_Stainless_14G_Spoke.html

DANS Comp sells Sapin Stainless 2.0's for one great price... shipping is very reasonable too. Every order I have made with them goes out that same day. Any length you want too. Sapin Strongs also.. not listed in their catalog.. just tell the order clerk you want them. Half a buck for them...:thumb:
http://www.danscomp.com/products/435905/Sapim_Stainless_14G_Spoke.html

Thanks for the link, but if only it were that easy ... shipping to Italy from the US involves a lot of cost and plenty of tax ... And there aren't as many places selling spokes online in the EU. I guess I should also mention that the ACI Alpina spokes available in the shops here are very cheap, and of comparable quality to, the DT Swiss options I can order online. So cost is something that's on my mind.

All the opinions and advice are appreciated, btw.

Wheelsmith nipples are effectively 1mm longer than DT nipples. Use the wheelsmiths if there is some thread showing with the DT's. You can file down a spoke that is too long I use the sidewalk. http://zerodish.wordpress.com/

Wheelsmith nipples are effectively 1mm longer than DT nipples. Use the wheelsmiths if there is some thread showing with the DT's. You can file down a spoke that is too long I use the sidewalk. http://zerodish.wordpress.com/

Thanks for the tip. We don't get wheelsmith stuff here, but I have a bunch of Alpina nipples that if I remember correctly are 12mm and 14mm, so I could try them in a pinch.

After all this, I think I've found the one shop in the city that will suffer the extreme inconvenience of having to sell its customer what he wants. Let's see if this friendliness transfers from the phone to a face-to-face encounter. Fingers (3) crossed.

If you are building with alloy nipples, get longer spokes. If they don't thread all the way through the nipple, the nipple can and will break in short order.

BL

does 1 or 2mm really make a difference?



you might have asked "can one straw break a camel's back?" because the situation is similar.

From the ideal size - which I define as the spoke ending between the bottom of the slot and the top of the nipple - there's a tolerance of -1 or +2mm (the +2 depends on the thread depth of the spoke and nipple). So in theory 1-2mm should be OK, or at least 1mm is OK.

But, let's say that your calculation, or existing spokes are already at the short end of the range, ending about 1mm short of the slot. Now you're 1mm tolerance to the short end is already gone, so another 1mm would be a deal breaker. The same can happen at the long end of the range.

That's why, whenever anybody asks about rounding up or down, or going to the nearest available length spoke, I say that you need to know where you're starting from. If the existing spokes or calculation are at one end of the range, you must adjust back toward the center.

Thanks everyone. in the end, I managed to get speaking to a human being in Chain Reaction Cycles (a big online store here in Europe), who measured the rim and calculated spoke length for me based on the hubs I have and the nipple length etc. He was nice enough to get the stuff out of the warehouse and do it himself, so I'm confident that they'll be ok.

So: Pair of new Campy Record hubs, 32-hole open pro rims with DT competition spokes, 3 cross. And thanks to some thrifty shopping, all had for under €300 (is that about $400 US?). Not sure what that's like in the States, but for here it's a pretty good bargain. One place wanted €270 for the rear hub alone. With some love and attention, I should have some pretty nice wheels.

Just out of interest, I made the above choices based on a desire to combine as best I could reliability, reasonable weight and cost-effectiveness. I'd love to hear of anyone else's preferred wheel component combos, and what they weigh, how they perform etc. Ever since I built my first one last year, I never cease to be amazed just how great hand-built wheels can be.

Also, you really should encourage that LBS to get a spoke machine. If they give you the, "It's too expensive and we can't justify the cost..." line, there are quite a few here on BF who will tell you that spoke machines pay for themselves 10X over...

=8-)

Many shops don't build wheels anymore. I would certainly expect shops with a Peter White/Hiawatha/Rivendell type clientele to have a cutter, but there just aren't that many of that type of shop left. Even my LBS, where they appreciate "old" steel framed, wire wheeled steeds, sells nothing but pre-built wheels.

Many shops don't build wheels anymore. I would certainly expect shops with a Peter White/Hiawatha/Rivendell type clientele to have a cutter, but there just aren't that many of that type of shop left. Even my LBS, where they appreciate "old" steel framed, wire wheeled steeds, sells nothing but pre-built wheels.

That's certainly the case here in Rome. If I want a carbon race wheel and I have a sack of cash, there are places, but I've not found anyone who is capable or willing (not sure which, I think a little of both, perhaps) to build a wheel. They just point you to the Campagnolo or Fulcrum wheels on the wall. Which are fine and lovely, but not what I asked for!

So after my last post about the campy-DT comp-open pro combo for under $400, no one wants to offer up their opinion on the "best" custom combo?

The "best" custom combo is going to be the one that works for you and suits your riding style. What's your weight? What's your riding style (masher, spinner, sprinter)? What types of roads do you usually ride on? What size tires do you plan on running? Is weight more important than durability, do you want a compromise, or do you want wheels that will last you forever?

Personally, I've moved away from Mavic rims because of QA issues and now use DT and have had no problems. If I were to go with sewups, the Ambrosio Nemesis seem to be the go-to rim (good enough for Boonen, good enough for me). The wheels that I build for myself tend to be 32 hole, 3 cross, 14/15 front and NDS rear, and 14 DS rear. Brass nipples, as alloys aren't worth the risk...if the weight is important to you, and you're light enough, drop your spoke count to 28 to make up for that. FWIW, I use boiled linseed oil as a spoke prep.

For your original post, I would go with 293's and 291's, and not compromise. It can certainly work if you have to make it work, but I'm funny that way.

Pete

The "best" custom combo is going to be the one that works for you and suits your riding style. What's your weight? What's your riding style (masher, spinner, sprinter)? What types of roads do you usually ride on? What size tires do you plan on running? Is weight more important than durability, do you want a compromise, or do you want wheels that will last you forever?

Personally, I've moved away from Mavic rims because of QA issues and now use DT and have had no problems. If I were to go with sewups, the Ambrosio Nemesis seem to be the go-to rim (good enough for Boonen, good enough for me). The wheels that I build for myself tend to be 32 hole, 3 cross, 14/15 front and NDS rear, and 14 DS rear. Brass nipples, as alloys aren't worth the risk...if the weight is important to you, and you're light enough, drop your spoke count to 28 to make up for that. FWIW, I use boiled linseed oil as a spoke prep.

For your original post, I would go with 293's and 291's, and not compromise. It can certainly work if you have to make it work, but I'm funny that way.

Pete

Thanks Pete. I know that a real "best" is impossible to establish, and I'm pretty happy with my Record-Open Pro-DT Comp combo, as it was cost-effective, and it provides a good balance of weight and strength (as I mentioned, it's 32 hole, 3 cross). Just interested to know what everyone on here likes.

I went with the campy, as being in Italy and riding with Athena, it was a convenient choice. I like the look of Chris King, but they're expensive here – about double what I paid for the Record set. I chose the Open Pros based on reputation and the fact that they were €20 cheaper per rim compared to the DT Swiss RR415 I was looking at. What are the QA issues with Mavic stuff?

Pete, you also hit on something I meant to ask about: Spoke prep. You simply cannot buy it in Rome (where I live) or Dublin (where I'm from). I can't even buy it online from an EU shop. No one seems to use it, and I've always got away with using chain lube without any hassle. Is it worth sourcing?

Not being able to buy lower-range Campy hubs on their own is one of the reasons why I don't ride Campy. Even still, I'm considering building a "go-fast" (which is a relative term for me) frame with Athena alloy on it, just to have a "classic" road bike again (my current rides are a rando and a 650b rough stuff , both built by me).

As far as spoke prep, again, I use simple boiled Linseed Oil. If you can't find it at a hardware store, you might try an art supply store, as I believe linseed oil is used for thinning oil-based art paints. The boiled linseed oil sets up over a day or so. Dip the threaded ends of your spokes in the oil, let them sit for 15 minutes, and then build away.

Pete

Not being able to buy lower-range Campy hubs on their own is one of the reasons why I don't ride Campy. Even still, I'm considering building a "go-fast" (which is a relative term for me) frame with Athena alloy on it, just to have a "classic" road bike again (my current rides are a rando and a 650b rough stuff , both built by me).

As far as spoke prep, again, I use simple boiled Linseed Oil. If you can't find it at a hardware store, you might try an art supply store, as I believe linseed oil is used for thinning oil-based art paints. The boiled linseed oil sets up over a day or so. Dip the threaded ends of your spokes in the oil, let them sit for 15 minutes, and then build away.

Pete

Ok, thanks. I'll try the linseed oil. Do Campagnolo sell lower end hubs anymore? They only stock the record ones here. I remember chorus ones a few years back.

Do Campagnolo sell lower end hubs anymore? They only stock the record ones here. I remember chorus ones a few years back.

For the last few years, Campy only sold Record hubs for the after market. I suspect that it's because when all is said and done, there's very little difference in their cost to manufacture the various models, and also because hub after market demand is limited to begin with.

If anyonw wants I still have a dent number of Daytona, Centaur (same as Daytona) and Chorus hubs available mostly in 32h. The only condition is that while I'll gladly sell fronts alone, I won't do so with rears. Rears are only available as pairs with fronts. feel free to email me c/o the site below my signature. (fb@.....com)