A Much improved ebike spoke calculator,

[ebikedelight]

You want it to be in whatever pattern gives it as much side-to-side triangulation as possible.

Without that, sideloading can cause wheel problems.

Hopefully 1 day soon, someone will post a utube video outlining the procedure using a electric hub rear motor and a 26 inch fat bike wheel with a 1 cross pattern with 36 spoke , { since this seems to be a very common setup} clearly showing the best way to lace for strength and spoke adjustments for maximum truing ability.

As a newbie, I can clearly state that trying to take in all this info , is overwhelming and a 10 minute utube video showing the best way to do a 1 cross lace pattern with these 36 spoke ehubs/ fatbike rims , would be of great assistance.

There are videos on utube , but none of them seem to hit all the important points.

 

[ebikedelight]

The left and right spoke hole offset measurement ? ...Is this taken from the hub or rim ?

Thats a new 1 to me...how do I get that data ? Everytime I think im close to getting this down, a new measurement comes up I must make.

so far I got :

hub flange diam. 234

hub center/ flange center- 17.2

hub spoke hole diam - 3.2

number of spokes- 36

cross pattern - 1

and am waiting on mY fatbike rim to be delivered to get my ERD .

Wow, this is complex..and I havent even started lacing yet. lol.

 

[Obiwan007]

I know it seems overwhelming at first but remember that everyone the makes a video or walk through is normally trying to cover every possible combination of hubs, rims, frame clearance, frame asymetry, etc. Usually only a few of these apply to your specific project. I just laced up my first front fat tire rim a couple weeks ago. It was only my fourth wheel build. Two of those were with hub motors. Here is a pic:

It really was easy and I had to deal with a little bit of dish. I am currently holding off on lacing the hub motor until I get my fame modifications done and know how to much dish it. Here is my build thread:
http://endless-sphere.com/forums/viewtopic.php?f=2&t=67066
Measuring the spoke hole offset is easy and since it makes only a very small difference in the spoke length the exactness does not need to be perfect. Try:
Measure the rim width and divide by 2. This gives half the rim width, or the length from a side to the center. Now measure from the edge of the wheel to the center of a hole that is offset to that same side of the rim. Now subtract that measurement from the half rim width. The result should be the offset, or the measurement from rim center to the center of a spoke hole. Hope I got that right and I hope it helps you. With the new additions to this calculator by Justin, I believe it is the most powerful and flexible spoke calculator on the net hands down. Not just for e-bikes either! Just another way he has contributed to this list and the worldwide e-bike community. He and his business deserve our continued support. Thanks again J. Obiwan

 

[ebikedelight]

I know it seems overwhelming at first but remember that everyone the makes a video or walk through is normally trying to cover every possible combination of hubs, rims, frame clearance, frame asymetry, etc. Usually only a few of these apply to your specific project. I just laced up my first front fat tire rim a couple weeks ago. It was only my fourth wheel build. Two of those were with hub motors. Here is a pic:

It really was easy and I had to deal with a little bit of dish. I am currently holding off on lacing the hub motor until I get my fame modifications done and know how to much dish it. Here is my build thread:
http://endless-sphere.com/forums/viewtopic.php?f=2&t=67066
Measuring the spoke hole offset is easy and since it makes only a very small difference in the spoke length the exactness does not need to be perfect. Try:
Measure the rim width and divide by 2. This gives half the rim width, or the length from a side to the center. Now measure from the edge of the wheel to the center of a hole that is offset to that same side of the rim. Now subtract that measurement from the half rim width. The result should be the offset, or the measurement from rim center to the center of a spoke hole. Hope I got that right and I hope it helps you. With the new additions to this calculator by Justin, I believe it is the most powerful and flexible spoke calculator on the net hands down. Not just for e-bikes either! Just another way he has contributed to this list and the worldwide e-bike community. He and his business deserve our continued support. Thanks again J. Obiwan

do I measure the rim width , out side to outside..or inside to inside ?

QUOTE

Now measure from the edge of the wheel to the center of a hole that is offset to that same side of the rim.

END QUOTE

this has me very confused.

do you measure from the inside edge of the wheel or outside edge of the wheel ?

I dont understand the part " center of a hole that is offset to that same side of rim.

wow..this is really complex....no wonder why 99% of bicyclsits dont learn to do this.

 

[justin_le]

wow..this is really complex....no wonder why 99% of bicyclsits dont learn to do this.

ebikedelight, please go to the website that this topic is about here:

http://www.ebikes.ca/tools/spoke-calc.html

Every field is explained in detail in the text under the calculator and diagrams.
http://www.ebikes.ca/tools/spoke-calc.html#hub-settings
http://www.ebikes.ca/tools/spoke-calc.html#lacing-options
http://www.ebikes.ca/tools/spoke-calc.html#results

If you aren't able to read and process written text very well, then part of why we made a dynamic drawing of the laced wheel is so that you can SEE firsthand what all of the measurement parameters are for and what effect they have. So if you are confused about what the spoke offset is, then click in the number to increase or decrease the values and see how that changes the drawings of where the spoke holes are on the rim. It will be abundantly apparent what the number refers to if you just look at how the drawings change when you change the numbers.

Finally, if you have your own spoke threading tool and tons of spare spokes, then best is simply dive into building your first wheel, you could probably have already made the wheel in all the time spent posting all over the forum trying to solicit help! All the parameters and their meanings will be way more apparent when you have a rim and hub in your hands and are lacing up the spokes, and then I think you'll find this all a lot less confusing. If your spokes wind up a bit too long or a bit too short, then either live with it if it's just a few mm or cut and thread some more spokes to get it right.

There's not much more for you to do at this point other than waiting for the rim to arrive and then jumping in.

 

[ebikedelight]

wow..this is really complex....no wonder why 99% of bicyclsits dont learn to do this.

ebikedelight, please go to the website that this topic is about here:

http://www.ebikes.ca/tools/spoke-calc.html

Every field is explained in detail in the text under the calculator and diagrams.
http://www.ebikes.ca/tools/spoke-calc.html#hub-settings
http://www.ebikes.ca/tools/spoke-calc.html#lacing-options
http://www.ebikes.ca/tools/spoke-calc.html#results

If you aren't able to read and process written text very well, then part of why we made a dynamic drawing of the laced wheel is so that you can SEE firsthand what all of the measurement parameters are for and what effect they have. So if you are confused about what the spoke offset is, then click in the number to increase or decrease the values and see how that changes the drawings of where the spoke holes are on the rim. It will be abundantly apparent what the number refers to if you just look at how the drawings change when you change the numbers.

Finally, if you have your own spoke threading tool and tons of spare spokes, then best is simply dive into building your first wheel, you could probably have already made the wheel in all the time spent posting all over the forum trying to solicit help! All the parameters and their meanings will be way more apparent when you have a rim and hub in your hands and are lacing up the spokes, and then I think you'll find this all a lot less confusing. If your spokes wind up a bit too long or a bit too short, then either live with it if it's just a few mm or cut and thread some more spokes to get it right.

There's not much more for you to do at this point other than waiting for the rim to arrive and then jumping in.

someone has explained the spoke hole offset measurement, differently on this thread, compared to your instructions here :

Left Offset: This is the distance from the center of the rim to the left side spoke holes. If the rim holes are all in a row, then it would be left at 0mm
Right Offset: This it the distance from the center of the rim to the right side spoke holes. If the rim holes are not staggered, then it should be left at 0mm.

do I measure from center of my rim , to center of left/right side spoke holes ? Your instructions above dont specifiy if this measurement is to the center of the spoke holes in the rim .

 

[ebikedelight]

My ehub, is a very common hub sold on ebay...for a low price.

heres the link :

http://www.ebay.com/itm/291119531800?_trksid=p2059210.m2749.l2649&var=590270751129&ssPageName=STRK%3AMEBIDX%3AIT

If you wish to put this hub motor on your website , you could list it as :

EBAY SELLER XCESSORIES EHUB -48 VOLT- 1000 WATT - 26 INCH - 36 SPOKE HOLE , REAR MOTOR .

and heres the measurments I got on this hub :

hub flange diam. 234 -

hub spoke hole diam - 3.2

hub flange center - 17.2

number of spokes- 36

 

[Cowardlyduck]

Pure radial lacing is a foolish concept for a wheel that needs to transmit torque, while actually crossing the spokes with large diameter hubs in small rims leads to pretty extreme spoke angles at the rim which can cause its own problems.

I realise it was a while back on page 1, but it's interesting to see you say this Justin.

After a lot of research, opinions given, and consideration on my part, I went ahead and radially laced a Golden motor to a 20" rim for my Recumbent commuter.
http://endless-sphere.com/forums/viewtopic.php?f=6&t=57751&start=50#p960694

So far, this wheel has survived 2.5+KW/50+NM peaks, 2500+km, several bad crashes, and many bad pot holes, ruts and gutter drops, and not required trueing or spoke tightening once.
I think it helps that I had to cut and re-thread these spokes myself which did not leave as clean a thread as otherwise. Many of the spoke nipples were quite difficult to turn towards the end of building and initial truing of the wheel negating the need for any locktight etc.

I'm not sure what all the fuss is about radial lacing TBH...radial has worked fine in my case, and there are a number of other examples on ES of it working. I'm yet to see a failure from doing it on ES.

Cheers

 

[justin_le]

I'm not sure what all the fuss is about radial lacing TBH...radial has worked fine in my case, and there are a number of other examples on ES of it working. I'm yet to see a failure from doing it on ES.

The situation of a large diameter DD hub motor in a small 20" rim is one of the few cases where radial lacing makes sense, because the effective of windup to achieve a given torque transmission is greatly reduced and crossing is nearly impossible. Here is what I wrote on the spoke calculator website in regards to the cross pattern:

Cross Pattern: Most hub motors are laced with a single cross pattern. There is no point at all in having 2 or more crosses with the large flange diameters of most hub motors, and doing so will usually result the spoke entering the rim at a very difficult angle. Small geared hubs can be laced into large diameter (>26") rims with a double cross pattern OK, and large direct drive motors in small (<=20") rims usually can only be laced radially with 0 cross. If you have a motor with paired spoke holes, then a 0 cross pattern still has a spoke angle for transmitting torque, and there is no need for even single crossing the spokes.

Radial lace your motor into a 26" or 700c wheel and you'll find that unless you loctite the nipples it will get loose very fast. It's also much less of an issue with front motors as with rear motors, because on a front motor the torque is only coming from the motor and as a result is fairly steady. On a Rear motor that is being pedaled, you have a torque pulsation at every pedal stroke, with the spokes winding up and relaxing twice for each pedal rotation, and it doesn't take long for that kind of cyclic stress to wreck havoc on your radial wheel build.

A good rule of thumb should be that if you can cross the spokes, you should (unless of course you have a motor with paired spoke holes, in which case there is no need).

 

[Cowardlyduck]

Thanks for clearing that up Justin. Guess I should have read the site before posting.

Although you might be interested to know, the wheel pictured above is actually a rear. Mounted to my BikeE.

Although I don't pedal that hard most of the time on this bike, especially now that I'm running a 60t chain-ring up front.

Cheers

 

[John Bozi]

Pure radial lacing is a foolish concept for a wheel that needs to transmit torque, while actually crossing the spokes with large diameter hubs in small rims leads to pretty extreme spoke angles at the rim which can cause its own problems.

I realise it was a while back on page 1, but it's interesting to see you say this Justin.

After a lot of research, opinions given, and consideration on my part, I went ahead and radially laced a Golden motor to a 20" rim for my Recumbent commuter.
http://endless-sphere.com/forums/viewtopic.php?f=6&t=57751&start=50#p960694

So far, this wheel has survived 2.5+KW/50+NM peaks, 2500+km, several bad crashes, and many bad pot holes, ruts and gutter drops, and not required trueing or spoke tightening once.
I think it helps that I had to cut and re-thread these spokes myself which did not leave as clean a thread as otherwise. Many of the spoke nipples were quite difficult to turn towards the end of building and initial truing of the wheel negating the need for any locktight etc.

I'm not sure what all the fuss is about radial lacing TBH...radial has worked fine in my case, and there are a number of other examples on ES of it working. I'm yet to see a failure from doing it on ES.

Cheers

I broke my first spoke on my radially laced clyte 4065, but I did it while opening the motor for repairs.... I was surprised how easy it was to replace.

loosened 4 spokes either side, let down the tyre, pulled the tube to the side (no removal of tyre and tube), cut a bit of the rim tape and poked it in with the nipple, tightened them up....

now to true it once on the bike with a zip tie... my only concern is if any alu crumbs got left in the wheel.

 

[\/ampa]

Somewhere i have read in this forum that the maximum spoke angel for bicycle rims should be 8° .
After i got my MXUS with 1 cross and about 14° spoke angel i know why.
The nipple want exit straight out of the rim but the spoke don't which leaves warped spokes like in this picture.

So my advise is to better lace radial if spoke angel is above 8°. Its not optimal for torque transmission but i guess it holds longer than the other way.

 

[justin_le]

Somewhere i have read in this forum that the maximum spoke angel for bicycle rims should be 8° .
So my advise is to better lace radial if spoke angel is above 8°. Its not optimal for torque transmission but i guess it holds longer than the other way.

8 degrees is definitely too conservative, and if this is your criteria you'd wind up radial lacing every single direct drive hub motor on the market even in 26" and 700c rims, which would be a disaster. So please people don't follow this advice.

This is the paragraph that I wrote in regards to the spoke angle, and is a more sensible advice for hub motors builds:

Spoke Angle: This is the angle between the spoke and the tangent line of the rim. Generally speaking, if the angle is more than 80 degrees then it can be laced with relative ease. If the angle is less than 75 degrees, then the spoke nipples will have some difficulty in angling in the same direction as the spokes, and you may need to either put a bend in the spoke so that it enters the rim a bit more radially, or drill out the rim holes slightly larger so that the nipples have more freedom to pivot. Angles less than about 70 degrees are quite problematic and best avoided.

On the spoke calculator we are referencing the angle to tangent rather than to radial since it's easier to draw the theta on the image, and so the angle discussed is the 90 degree compliment in case people are confused. So your 8 degree reference would be the equivalent of 82 degrees in the above paragraph.

 

[\/ampa]

8 degrees is definitely too conservative, and if this is your criteria you'd wind up radial lacing every single direct drive hub motor on the market even in 26" and 700c rims, which would be a disaster. So please people don't follow this advice.

Yes 8 degrees seems conservative. Its more 8 to 12 degrees depending on nipple and nipple-hole sice. I have found now again the post where i have this number from.

Using bicycle rims and 14g polyax nipples, 8 degrees is my favored max. This usually requires drilling new holes in the hub for 0.5 cross pattern. On a 9 continent in a 26" rim it turns out to about 11 degrees with 0.5 cross which is acceptable. 12 degrees is really the limit to acheive proper tension without side loading the nipple.

From discussion on "What is acceptable spoke angle?" here http://endless-sphere.com/forums/viewtopic.php?f=2&t=61196

But the question is now is it better to bend the spoke if the angle is > 82°-78° and have a warped spoke/nipple relation or make a 90° radial lace.

 

[justin_le]

But the question is now is it better to bend the spoke if the angle is > 82°-78° and have a warped spoke/nipple relation or make a 90° radial lace.

Indeed, that is the question! I would answer that some side-loading the nipple is not much of a bad thing at all. It might not look or feel good to someone lacing the wheel, but in practice in the 10-15 degree realm it doesn't cause problem. We very rarely see spoke failures at the nipple, over 90% of the time it is at the elbow going into the hub flange. So I would take the bend at the nipple over the radial lace any day.

That said, I also like to base things on evidence and we don't have any firsthand experience with radial lacing hubs into 26" wheels since it just seems like a bad idea. If someone on the forum has a good sample size (>10 wheels preferably) of radial laced builds in 26" rims I'd be all ears to hear how that panned out. I can say that we have a lot of experience with 20" wheels being radially laced. At one point eZee switched their stock 20" build on us from single cross to radial; it's a geared motor so smaller in diameter than the common 205mm direct drive hubs. I was skeptical but rolled with it and sure enough almost all the people who got rear kits ended up complaining about their spokes always going loose and requiring re-tightening on a weekly basis. A number of these came back to us and we rebuilt them single cross to good effect.

The 20" rear Crystalyte motors we have are laced radial, and we definitely have a higher proportion of customers with spoke issues on these wheels than with the 26" kits which are single cross, but it's at a tolerable enough level. Next batch though I may try to get Crystalyte to do a paired hole drilling, since that really is the best solution.

-Justin

 

[ebikedelight]

But the question is now is it better to bend the spoke if the angle is > 82°-78° and have a warped spoke/nipple relation or make a 90° radial lace.

Indeed, that is the question! I would answer that some side-loading the nipple is not much of a bad thing at all. It might not look or feel good to someone lacing the wheel, but in practice in the 10-15 degree realm it doesn't cause problem. We very rarely see spoke failures at the nipple, over 90% of the time it is at the elbow going into the hub flange. So I would take the bend at the nipple over the radial lace any day.

That said, I also like to base things on evidence and we don't have any firsthand experience with radial lacing hubs into 26" wheels since it just seems like a bad idea. If someone on the forum has a good sample size (>10 wheels preferably) of radial laced builds in 26" rims I'd be all ears to hear how that panned out. I can say that we have a lot of experience with 20" wheels being radially laced. At one point eZee switched their stock 20" build on us from single cross to radial; it's a geared motor so smaller in diameter than the common 205mm direct drive hubs. I was skeptical but rolled with it and sure enough almost all the people who got rear kits ended up complaining about their spokes always going loose and requiring re-tightening on a weekly basis. A number of these came back to us and we rebuilt them single cross to good effect.

The 20" rear Crystalyte motors we have are laced radial, and we definitely have a higher proportion of customers with spoke issues on these wheels than with the 26" kits which are single cross, but it's at a tolerable enough level. Next batch though I may try to get Crystalyte to do a paired hole drilling, since that really is the best solution.

-Justin

My wifes ebike is a dolomite fat bike with 1000 watt brushless hub motor mounted to the front 26" tire.

Its been to cold here to put alot of miles on it, to see if the spokes come loose....but I have a simple remedy for that issue anyways.

Once the wheel had been radially spoked , I took a tube of clear silicone and dabbed the head of each spoke nipple inside the rim with silicone . I used enough so it covered the whole head of the spoke nipple and covered the surrounding circular area of the rim a few millimeters around the head of the spoke nipple . I then smoothed it out with my finger, let it dry for 24 hours, then applied my rim tape . Im hoping this will accomplish 2 things.

1. ensure that a spoke nipple/ spoke head will never puncture my tube

2. provide more then enough adhesion to hold the spoke nipple/ spoke in place so they wont ever loosen.

The good thing about using a adhesive like silicone for this mod, is it is very strong once dry, it is pliable and it can be easily removed later on, if need be .

 

[dragonlady5]

After putting almost 30,000 km on ebikes over the last 3 years the issue of spokes, their tension and rims are definitely a prime consideration of mine which I have yet to solve.

-Checking tension (Park tool) is not always possible, no room on one side with Bionx 500 Watt motor.
-With 500 motors (and more in some modes and models) in the middle of the wheel, the stress and strain produced are beyond design intent for most spokes and rims. E.g every tried to put out 500 Watts of muscle.
-All three bikes I've had ended up with higher tension on the cassette side which would never balance.
-Rims (most I have seen) which come with Ebikes were never designed for ebike applications and will not last, as long as they should.

The first two bikes I rode had the 8FUN hub motors, I don't recall specs on the rims but it was a struggle to keep the rim aligned, the shorter spokes reduce the amount of flex in the system which ended up causing noisy spokes (clinking under load), rim alignment issues, and one rim which ended up with a 6 inch split on the side wall

The most recent ride has one of the latest Bionx hubs, this hub is positioned between the spokes so that full length spokes can be used (access with Park tool on only one side). After almost 10,000 km on this ride I had no issue with alignment or noise, a big improvement.

BUT after saying all the nice things, this weekend I just discovered a series of cracks in the rim which I can only put down to metal fatigue. Back to the manufacturer for a replacement, but on the hunt for a indestructible rim....

 

[parabellum]

After putting almost 30,000 km on ebikes over the last 3 years the issue of spokes, their tension and rims are definitely a prime consideration of mine which I have yet to solve.

-Checking tension (Park tool) is not always possible, no room on one side with Bionx 500 Watt motor.
-With 500 motors (and more in some modes and models) in the middle of the wheel, the stress and strain produced are beyond design intent for most spokes and rims. E.g every tried to put out 500 Watts of muscle.
-All three bikes I've had ended up with higher tension on the cassette side which would never balance.
-Rims (most I have seen) which come with Ebikes were never designed for ebike applications and will not last, as long as they should.

The first two bikes I rode had the 8FUN hub motors, I don't recall specs on the rims but it was a struggle to keep the rim aligned, the shorter spokes reduce the amount of flex in the system which ended up causing noisy spokes (clinking under load), rim alignment issues, and one rim which ended up with a 6 inch split on the side wall

The most recent ride has one of the latest Bionx hubs, this hub is positioned between the spokes so that full length spokes can be used (access with Park tool on only one side). After almost 10,000 km on this ride I had no issue with alignment or noise, a big improvement.

BUT after saying all the nice things, this weekend I just discovered a series of cracks in the rim which I can only put down to metal fatigue. Back to the manufacturer for a replacement, but on the hunt for a indestructible rim....

I solved inadequate rim/tire issue with motorcycle/moped rim, tire and spokes. At >60kph and multi KW input bicycle stuff just falls apart, even motorcycle parts are not pothole proof but greatly reduce casualty's

 

[Golyo]

This calculator doesn't work for me. Strange thing is that yesterday I had no problem with it.
Could someone else check it please?

 

[justin_le]

This calculator doesn't work for me. Strange thing is that yesterday I had no problem with it.
Could someone else check it please?

Indeed, something just broke and we're looking into this. Thanks for bringing it to our attention.

 

[justin_le]

Indeed, something just broke and we're looking into this. Thanks for bringing it to our attention.

Should be fixed now, but you may need to refresh/reload your browser for it to update all the files and not use the cached ones:
http://www.ebikes.ca/tools/spoke-calc.html


What happened is that there were some overlooked dependencies and shared code with the trip simulator application that we're working on at the moment.

 

[Golyo]

Thanks for fixing it! Because of it I could order the spokes for my wheel.

 

[Merlin]

tried this crazy crossing of spokes for an fatbike rim
....its a well known mxus 3000, but spokes are to long from this calculator. 2/3mm.
wasnt possible to true it. Nipples threads was at the end

I have a quick question.

Quick answer is that the 5 data stats you referenced are insufficient. You will also want to get the flange spacing of the hub (distance between the left and right spoke flanges, super easy to measure) as well as the left and right spoke hole offsets in your rim (also pretty easy to measure). If on the spoke calculator the spokes wind up going straight up and down rather than angled into each other with triangulation, then you will want to use the "Swap Spokes" option if simply putting the spoke elbows on the outside does not result in sufficient triangulation. This diagram illustrates the issue with a narrow flange hub motor like you have going into a typical fat bike rim, and the effect of the different lacing options in the spoke calculator:

Id like to keep this build as simple as possible and make all 36 spokes the same length , instead of having different sized spokes for the freewheel side . I dont even care if I lose the ability to use all the gears on my rear freewheel since this is a ebike and I wont be using the gears or pedalling much anyways .

Dishing actually has less to do with enabling the use of gears as it does with having the tire sit centered in the bike without it rubbing against the left or right stays.

This ehub was made for 12-13 gauge spokes , but my donor spokes are all 14 gauge . Will 14 gauge be strong enough

14 gauge is more than strong enough, and your rim will have spokes holes meant for 14g nipples as well.

and where do I purchase the spoke washers to slip over the head of the 14 gauge spoke to seat it properly in the 12 gauge ehub hole ?

Same place you would purchase any washers, from a hardware store or fastener supply shop.