Wheel Build Advice Thread

[blacksp20]

Unless you are having a crack at a WC Downhill Event or EWS you probably don’t really need triples.

I most definitely am not.



Brains trust, can I run some numbers by you please.

I've punched my numbers through prowheelbuilder and DT and got similar numbers for required spoke lengths.
Front 290.4 L and 291.9 R - DT recommended 290/292
Rear 291.1 L and 289.9 R - DT recommended 291/290

Would there be an issue if I went with 291 all round to simplify things or should I stick to the recommended lengths?
Will be using SAPIM Race spokes with SAPIM brass 12mm nips and using washers supplied with rims.

 

[creaky]

Would there be an issue if I went with 291

Can you source 291s, including easily for replacements in the future?

 

[SummitFever]

Always round down. 291s or 290s all round should work fine. There is a bit of stretch in the SAPIM Race spokes (not us much as the Lasers) as you get them up to final tension, so rounding down 1 or 2mm is normally not an issue.

 

[blacksp20]

Can you source 291s, including easily for replacements in the future?

I'll be ordering from the UK from a custom spoke cutter and was planning to buy 6 extra spokes as a safety net.

Always round down. 291s or 290s all round should work fine. There is a bit of stretch in the SAPIM Race spokes (not us much as the Lasers) as you get them up to final tension, so rounding down 1 or 2mm is normally not an issue.

Ok. I've just had another read of the bible and I'm going to redo my ERD calculation as I don't think I was quite as accurate as I should have been. Going to redo and will report back.

 

[Ackland]

Always round down. 291s or 290s all round should work fine. There is a bit of stretch in the SAPIM Race spokes (not us much as the Lasers) as you get them up to final tension, so rounding down 1 or 2mm is normally not an issue.

Yeah I'd just order a box of 290's

 

[The Duckmeister]

I'll be ordering from the UK from a custom spoke cutter and was planning to buy 6 extra spokes as a safety net.

Just a heads up, be prepared for a wait, 'cos shipping is up the shit at the moment.

 

[blacksp20]

Just a heads up, be prepared for a wait, 'cos shipping is up the shit at the moment.

Yeah I’m expecting a lengthy wait. I’m not in a huge hurry as my current wheels are still spinning. The cost difference is definitely worth it though.

Can someone give me the best way of measuring ERD from experience? The bible says to use 200mm spokes, screwed into nipples until they are in line with the groove in the nipple then measure the distance between the spokes and add 400mm. To me this would measure longer than the bed ERD by a few mil or am I wrong?

 

[Ackland]

Yeah I’m expecting a lengthy wait. I’m not in a huge hurry as my current wheels are still spinning. The cost difference is definitely worth it though.

Can someone give me the best way of measuring ERD from experience? The bible says to use 200mm spokes, screwed into nipples until they are in line with the groove in the nipple then measure the distance between the spokes and add 400mm. To me this would measure longer than the bed ERD by a few mil or am I wrong?

Which rims?

Last time I crunched numbers, R2 bike was the best pricing on Sapim to Aus

 

[Flow-Rider]

Yeah I’m expecting a lengthy wait. I’m not in a huge hurry as my current wheels are still spinning. The cost difference is definitely worth it though.

Can someone give me the best way of measuring ERD from experience? The bible says to use 200mm spokes, screwed into nipples until they are in line with the groove in the nipple then measure the distance between the spokes and add 400mm. To me this would measure longer than the bed ERD by a few mil or am I wrong?

Use the nipples that you plan to build with to do your measuring, the end of the spoke thread needs to land in the right place on the spoke-nipple. I've never had an issue with using the manufactures ERD as some rims can be oval when they're unloaded by spoke lacing so you may end up with a false reading anyway.

 

[teK--]

I most definitely am not.



Brains trust, can I run some numbers by you please.

I've punched my numbers through prowheelbuilder and DT and got similar numbers for required spoke lengths.
Front 290.4 L and 291.9 R - DT recommended 290/292
Rear 291.1 L and 289.9 R - DT recommended 291/290

Would there be an issue if I went with 291 all round to simplify things or should I stick to the recommended lengths?
Will be using SAPIM Race spokes with SAPIM brass 12mm nips and using washers supplied with rims.

Ideally you can run 291 as a single length across the board; easier to keep spare spokes.

The only risk I see is on the front left and rear right you might end up with spokes which are too long (since they stretch a tiny bit as you tension them up. You might then bottom out before you reach correct tension. It's not the end of the world as you can overdrive the nipples which means you lose one or two threads at the bottom of the nipple, and it's of little consequence since most of the load bearing is up the top near the rimbed.

If you want to play it safe, get half 290 and half 291 which should be optimal and give you extra threads to add extra tension later on if the spokes stretch further, or you buckle the rim slightly and need to straigten up the wheel.

EDIT: I assume to get the ERD figure, you actually measured the rims yourself using your preferred spoke and nipple combination? Never use the ERD figure provided by the rim manufacturer.

 

[teK--]

Yeah I’m expecting a lengthy wait. I’m not in a huge hurry as my current wheels are still spinning. The cost difference is definitely worth it though.

Can someone give me the best way of measuring ERD from experience? The bible says to use 200mm spokes, screwed into nipples until they are in line with the groove in the nipple then measure the distance between the spokes and add 400mm. To me this would measure longer than the bed ERD by a few mil or am I wrong?

that's the correct method. I usually screw the nipples down where the slot is level with the spoke end, and then I wind it down further one full turn. This accomodates for spoke stretch during building.

You are not actually measuring the rim bed diameter. You are measuring how far apart the ends of two opposing spokes should be.

 

[Flow-Rider]

EDIT: I assume to get the ERD figure, you actually measured the rims yourself using your preferred spoke and nipple combination? Never use the ERD figure provided by the rim manufacturer.

No problems here, built over 20 rims.

 

[teK--]

No problems here, built over 20 rims.

You're lucky then

DT nipples in particular depending on what length you are using, will hugely affect the correct ERD measurement.

So if using other branded nipples with DT rims, or vice versa etc.... need to be careful again.

 

[blacksp20]

Which rims?

Last time I crunched numbers, R2 bike was the best pricing on Sapim to Aus

Spank 350

R2 is not even close on price. 87 euro/A$142 compared to 42 pound/A$76 from spokesfromryan.co.uk and 48 pound/A$87 from customcutspokes.co.uk for 70 spokes and nipples. R2 want 40 euro just for shipping.

that's the correct method. I usually screw the nipples down where the slot is level with the spoke end, and then I wind it down further one full turn. This accomodates for spoke stretch during building.

You are not actually measuring the rim bed diameter. You are measuring how far apart the ends of two opposing spokes should be.

OK this makes sense. I will try and source two spokes and Sapim nipples and get measuring again. For what it's worth, my measurement came out at 601mm which is the same as Spank's quoted ERD but I measured using the supplied 0.8mm washers. Not sure if Spank calculate the ERD including them or not.

Ideally you can run 291 as a single length across the board; easier to keep spare spokes.

The only risk I see is on the front left and rear right you might end up with spokes which are too long (since they stretch a tiny bit as you tension them up. You might then bottom out before you reach correct tension. It's not the end of the world as you can overdrive the nipples which means you lose one or two threads at the bottom of the nipple, and it's of little consequence since most of the load bearing is up the top near the rimbed.

If you want to play it safe, get half 290 and half 291 which should be optimal and give you extra threads to add extra tension later on if the spokes stretch further, or you buckle the rim slightly and need to straigten up the wheel.

I'd be happy with the 290/291 idea as it means less chance of me getting the lengths mixed up when lacing. Both of the above UK sites have ample stock of both lengths so supply isn't an issue.

 

[teK--]

OK this makes sense. I will try and source two spokes and Sapim nipples and get measuring again. For what it's worth, my measurement came out at 601mm which is the same as Spank's quoted ERD but I measured using the supplied 0.8mm washers. Not sure if Spank calculate the ERD including them or not.

If they specify using washers, then in theory their ERD should include the washer thickness.

The only trouble with factory ERD measurements is you have no idea what nipple length or brand they used to achieve that measurement.

Here is a pic from Roger Musson's wheel building book which shows how nipple length can in turn affect ideal spoke length.

 

[Ackland]

R2 is not even close on price. 87 euro/A$142 compared to 42 pound/A$76 from spokesfromryan.co.uk and 48 pound/A$87 from customcutspokes.co.uk for 70 spokes and nipples. R2 want 40 euro just for shipping.

Woah! I got a load of Sapim Lasers for less than $100 shipped not that long ago. (shipping was 20 euro)

Just checked spokes from Ryan... I'll be using them in the future!

 

[blacksp20]

If they specify using washers, then in theory their ERD should include the washer thickness.

The only trouble with factory ERD measurements is you have no idea what nipple length or brand they used to achieve that measurement.

Here is a pic from Roger Musson's wheel building book which shows how nipple length can in turn affect ideal spoke length.

View attachment 365426

Yeah Roger’s book is what I’ve been reading and referring to as the bible.
I can’t source Sapim spokes/nipples locally to measure ERD, so if I use a nipple of the same length and similar shape, will I get a measurement that is close enough to use?
Only other option is to switch to DT gear as I can source them at all local shops to make my measuring tool. Building with DT will increase the price of my build though and Ryan doesn’t stock them, and he has Park TM-1 for a good price.

 

[Flow-Rider]

Washers usually come with the rims, if it's calculated in the ERD.

You're lucky then

DT nipples in particular depending on what length you are using, will hugely affect the correct ERD measurement.

So if using other branded nipples with DT rims, or vice versa etc.... need to be careful again.

Spoke tip is always going to end in the same position in relation to the rim and nipple head, if you've used the correct length spoke. I've always used DT spokes and nips unless I'm doing a hub swap over or can't find any DT spokes in stock. You can never find the exact spoke length unless you cut and forge your own threads on the spokes or get someone else to do it.

 

[Oddjob]

Yeah Roger’s book is what I’ve been reading and referring to as the bible.
I can’t source Sapim spokes/nipples locally to measure ERD, so if I use a nipple of the same length and similar shape, will I get a measurement that is close enough to use?
Only other option is to switch to DT gear as I can source them at all local shops to make my measuring tool. Building with DT will increase the price of my build though and Ryan doesn’t stock them, and he has Park TM-1 for a good price.

You are over thinking it. 292mm all round would be ok. A couple of mm too long won't impact the wheel build.

The difference between a Sapim Polyax and Dt brass would be immaterial as well.

Dt nipple washers are 0.8mm but I've found Dt erds from the website to be spot on.

The more important things in my mind are thread lube, build process and a tensiometer. I use Lanotec for thread lube as its a anti-seize that dries a bit sticky. Ali Clarksons youtube video is a good summary and covers most of the same things as Musson's book.

Sent from my SM-G970F using Tapatalk

 

[teK--]

Yeah Roger’s book is what I’ve been reading and referring to as the bible.
I can’t source Sapim spokes/nipples locally to measure ERD, so if I use a nipple of the same length and similar shape, will I get a measurement that is close enough to use?
Only other option is to switch to DT gear as I can source them at all local shops to make my measuring tool. Building with DT will increase the price of my build though and Ryan doesn’t stock them, and he has Park TM-1 for a good price.

PM me I'll put a couple of Sapim nipples in the mail for you.