wheel lacing insanity, please help!

ok, i am going a little nuts here. totally blew my budget on spokes from cognito moto (buchanans), and i'm having a real problem getting them to work on my rear hub. i am lacing up a 17" drop center rim to my '76 honda cb750 hub and a 19" harley drop center rim to my cb750 front hub. the front laced up no problem, it came together beautifully and is everything i dreamed it would be. the rear, on the other hand, is giving me some problems.

i laced up the inner spokes on each side without a hitch. i then started on the outers on one side, and was only able to get 7 out of 10 in on that side because everything was getting too tight and i had no wiggle room any more. just for kicks, i flipped the wheel over to see if i could get any outers to work on that side, and no way, i couldn't get anywhere near the rim holes i needed to be in. something was holding the rim to the other side of the hub, and tight.

so i walk away before i lose my cool, and then go back and try again. i did all the inners once again, and did only 4 outers, evenly spaced, on one side before flipping to see if i could get any outers on the other side again. still no dice! something about putting the outers on the first side was eating up any slack i needed for the other side. so i snoop around, and it seems like on the first side i put them on, the swaged area of the outer spokes is right up against the edge of the hub, like so:



this would explain why when i flip the wheel over, i have no slack to get the outers spokes to their appropriate holes. the outers on the first side cannot reach the appropriate angle and are being held out by the swage/edge of the hub, thus holding the rim away from the other side of the hub

my question is, what the heck do i do? i was thinking of filing little grooves in the edge of the hub for the swaged areas to seat into the hub flange so the outer spokes could angle in more, but it seems like i should be able to lace these up without such drastic measures. i tried contacting devin at cognito moto for some tips, as i figured he's built a few 750's with these spokes, surely he's dealt with something like this. that was earlier today and i haven't hear anything back yet. i know he's busy and i don't want to be a pest, so if anyone else has any clues, please let me know.

is it possible the outer spokes need a different bend or slightly longer head, or do i have to butcher my powder coated rim? hopefully there's a solution that doesn't include spending more money :-\

oh, and here's my lacing pattern, if that helps at all. just have the inners on in this pic, as well as one outer just to show what direction i'm heading.

Your lacing appears correct, and it looks like the spokes are the right length. Many hubs have strong contact with the swagged end of the spoke, which is evident when you disassemble the wheel. My guess is that your rim is simply too small a diameter for the dimensions of the hub. The drop center combined with the smaller than stock diameter makes a very considerable change, which is made more profound by the relatively large hub diameter. Consider that the smaller diameter not only makes the angle between the width of the hub to the centerline of the rim much greater, but also the angle as viewed from the side. The combination makes spoke overlap on the hub very long and makes the max hub diameter intrude into the space the spoke takes to get to its hole in the rim. Probably the best solution would have been to machine the outside edge of the flange to an angle that aligns with the centerline of the new rim. If you look at really large hubs, like a 4 leading shoe drum like a GT750 Suzuki or an old racing brake, the outside face of the hub where the spokes go is angled pretty steeply because the rim is so close. The spokes should already be bent correctly (if made by Buchanan). You could add a bend where the spoke passes the edge of the hub, which would enable you to assemble the wheel, but I think this is a terrible idea. It will cause the existing bend to be incorrect, and create an angle in what should be a straight line path between the loaded end points. Wish I had something more encouraging.

Spokes are too short. Just because Cognito makes sweet parts does not mean he makes no mistakes. Everybody does, explain the problem, and if he's a stand-up guy he'll give you the right spokes. Thats what you paid for

Spokes tend to be on the dark side now and then, i've had it a couple times. No big deal at all, hapens more then you'll want to know.

Are you leaving the nipples loose? If you tighten all the inners, you won't have room to get the outers in. LEave all the nipples loose, just a thread or 2 holding them on...then you should be able to get the outers on by moving the rim away from the hub in the area you are lacing.

Once all are in, then carefully start tightening, making sure the hub and rim remain concentric, tightening each spoke a little at a time as you go around....

Bert Jan said:

Spokes are too short. Just because Cognito makes sweet parts does not mean he makes no mistakes. Everybody does, explain the problem, and if he's a stand-up guy he'll give you the right spokes. Thats what you paid for

Spokes tend to be on the dark side now and then, i've had it a couple times. No big deal at all, hapens more then you'll want to know.

Click to expand...

The spokes actually seem to be a good length, what makes it seem that they are too short? Maybe I didn't explain my problem well enough, but the spokes aren't having a hard time reaching their appropriate holes because they are short, but because they are not angled enough. I would have to bend them a good deal to get them threaded into the nipple, but the would reach just fine length wise.

And I actually did hear back from Devin. He said it is definitely an option to send them back to Buchanan's, so I may have to go that route.

Jpmobius, I understand and agree with what you're saying, but people have been lacing these hubs to even smaller rims than I am for years, so there has to be a way. Machining the lips down, as you said, would be ideal, but I am wondering if slightly longer heads on the outer spokes along with a sub 90* bend would do the trick.

Also, yes, I am leaving all the spokes as loose as possible while assembling.

You need outers with a tighter angle than stock 90 degrees. The alternative is to lace it up and let the spokes straighten themselves out so to speak.

When you start to tighten and true, the trick is to tighten and true just the inners leaving teh outers loose. When it's trued, tighten the outers carefully to the same tension as the inners and it should only need the smallest amount of tweaking

having the outer spokes bent is not ideal for sure but the fact is they are bent where they go through the hub flange as well... they are under tension not compression so as long as the bend is correctly placed so the spoke follows the profile of the flange stregnth is not compromised,in other words if they need to be bent then they actually should be bent and not just "bowed" and the bend needs to be exactly at the flange
the way ide doit is get it going together all spokes and use a perfrectly placed whap with a plastic hammer to bend the spoke
for sure you will want to keep an eye on spoke tension(as always) it may take an extra session or 2 after riding to finalize the spoke tension

xb33bsa said:

having the outer spokes bent is not ideal for sure but the fact is they are bent where they go through the hub flange as well... they are under tension not compression so as long as the bend is correctly placed so the spoke follows the profile of the flange stregnth is not compromised,in other words if they need to be bent then they actually should be bent and not just "bowed" and the bend needs to be exactly at the flange
the way ide doit is get it going together all spokes and use a perfrectly placed whap with a plastic hammer to bend the spoke
for sure you will want to keep an eye on spoke tension(as always) it may take an extra session or 2 after riding to finalize the spoke tension

Click to expand...

the swaged area of the outer spokes is sitting perfectly on the hub flange, as you can see in the pic. my problem is that they would still need to bow considerably to get to their dimples in the rim.

just to be clear, where are you suggesting to give them extra bend? would it be the green circle or the red?

teazer said:

You need outers with a tighter angle than stock 90 degrees.

Click to expand...

this was my thinking as well. however, with a tighter angle, the head would also need to be lengthened a bit to give a little more clearance over the edge of the hub flange.

hold on, are the spoke holes countersunk for the head ? it looks like the head is very proud on that outer spoke

the front side of the holes is stepped, but the back side is not. so the inner spokes are countersunk, but the outer ones are not.

huh,ok
well the bend would be at the green not at the red
but are you sure the spokes are in the right holes in the hub ?

I just checked the hub, all the holes are exactly the same. Stepped on the face of the hub, and chamfered on the back. You had me excited there for a minute though, haha

Well if you are going to bend the spokes, you might want to consider making a little jig. I have had to add a little extra bend to spokes a few times, (increasing the existing bend) to get a better fit, but you could add an additional bend at your green circle. You could probably do it by smacking the spokes with a hammer per XB's suggestion, but I would worry about chipping off your new paint. A little jig is super easy to make. I made mine with a piece of 3/8" steel plate. I threaded two bolts onto it and locked them in with nuts on the back side. I used bolts with a diameter to match the existing bend radius that were not threaded all the way to the head. I screwed them into the plate all the way down so only the unthreaded portion was exposed so the spokes rested on a smooth surface, and placed them so one bolt rested in the existing bend and the other hooked under the head of the spoke on the other side. I put a couple of washers on the bolt that makes the bend to hold the spoke parallel with the plate, otherwise the large head rotates the spoke and your bend is not parallel to the original - more important for your extra bent because you need your two bends to be in the same plane. Clamped it in a vise, and with a couple trials figured how far to bend each spoke by hand and made a mark on the plate. Only takes a few minutes to bend all the outer spokes (well there is only 18 or 20). You could just add an additional bolt where your green circle is and add the extra bend. Figure out what it takes for a perfect fit on one, and knock out all the rest. Looks like just a small bend will keep the spoke off the edge of the hub and your paint intact.

This seemed like a bad idea to me at first, mostly from a "not the right way to fix the problem standpoint", but thinking about it, it really should be fine.

I was thinking the same thing, a jig would be my best option. As some one said earlier, it shouldn't be a problem to get new ones made since I paid for them, but it took over a month for Buchanan's to get them to me. I don't feel like waiting that long, so I may just attempt the extra bend method.

UNLESS someone has an opinion on getting new ones made with longer heads and a more drastic bend. Would that be a better option, one worth the wait?

having a longer end with more bend in my opinion is a poor solution ,spokes "bed in " and require tightening/tuning after rides mailny becuse the bend at the end is under the most strain and straightening out for lack of a better decrip
you really want the spoke to hug the flange as close as possiblle on its path
i like the idea of a presision bend as outlind by the wise one,jpmoses, and it would be a huge bummer to chip the paint,remember the bend you make wants to be in the same plane as the end bend

There is a really good reason to not increase the length of the leg that rests in the hub. No matter how many bends, or length and direction of segments, there are only two points of contact (momentarily disregarding the whole problem you are having with contact on the outer diameter of the hub): The nipple on the one end and the point of contact where the spoke rests in its hole in the hub. This point of contact is not actually the bend. Tension between these two points tries to straighten out the bend in the spoke. The process of creating the rather extreme bend in the spoke work hardens that area, making it very much harder to "unbend" than it was to bend it in the first place. It is also much more rigid than the straight portion of the spoke heading toward the rim. The result of which is to bend that straight portion near the bend in the opposite direction in an attempt to make the straight long portion of the spoke to come into alignment between the two points of load. This is quite visible on most wheels if you look closely- some more than others depending on tension and use/abuse. (I just now went and looked at two wheels, one from an almost zero miles CB450 laced by Honda (only barely noticeable) and my old race bike, laced by me (very noticeable!). So making the bent portion longer will only add leverage to this issue and work against your goal. Imagine making it absurdly long like an inch, and you can see what would happen. No doubt the ideal scheme would be to form the end of the spoke like a question mark so spoke could "aim" at the right spot in the hub flange, but obviously it just isn't necessary. The "crude" way we all accept works just fine. I little tweak to keep the spoke off the paint shouldn't put things too far out of whack and solve your issue with just a little work and no extra expense.

xb and jpmobius, i was wondering that same thing. a longer head on the spoke would cause a lot more leverage to be placed on the bend. so i suppose i will be getting a jig together to try and add a slight extra bend to my outers in the area of the green circle.

thank you all for your kind help and input, can't tell you how much i appreciate your expertise. i will update this thread with the results!

jpmobius said:

There is a really good reason to not increase the length of the leg that rests in the hub. No matter how many bends, or length and direction of segments, there are only two points of contact (momentarily disregarding the whole problem you are having with contact on the outer diameter of the hub): The nipple on the one end and the point of contact where the spoke rests in its hole in the hub. This point of contact is not actually the bend. Tension between these two points tries to straighten out the bend in the spoke. The process of creating the rather extreme bend in the spoke work hardens that area, making it very much harder to "unbend" than it was to bend it in the first place. It is also much more rigid than the straight portion of the spoke heading toward the rim. The result of which is to bend that straight portion near the bend in the opposite direction in an attempt to make the straight long portion of the spoke to come into alignment between the two points of load. This is quite visible on most wheels if you look closely- some more than others depending on tension and use/abuse. (I just now went and looked at two wheels, one from an almost zero miles CB450 laced by Honda (only barely noticeable) and my old race bike, laced by me (very noticeable!). So making the bent portion longer will only add leverage to this issue and work against your goal. Imagine making it absurdly long like an inch, and you can see what would happen. No doubt the ideal scheme would be to form the end of the spoke like a question mark so spoke could "aim" at the right spot in the hub flange, but obviously it just isn't necessary. The "crude" way we all accept works just fine. I little tweak to keep the spoke off the paint shouldn't put things too far out of whack and solve your issue with just a little work and no extra expense.

Click to expand...

straight pull hub/spoke designs with no bend have been adopted pretty much universally,for the last 20+ years ,BSA was a pioneer as far as i know with the crinkle hub,then it was put into wide use starting about 1980 by the japs with the MX bikes ,a pretty much arrow straight spoke really solves the issue
BSA QD hub

so i got around to adding a bend to my spokes today, and they turned out great! although jpmobius had a good idea for a jig, i went a different route with mine. i drilled a hole in a sheet of steel that i had, and oriented it so that when i laced a spoke through the hole, the spoke would hang over the edge of the steel right where i needed the bend to be. i then looked for something to slip over the shaft of the spoke up to where i wanted the bend so that when i applied leverage, the bend would form in the appropriate area. a locking strap from my craftsmen tool chest fit the bill, so that was nice. this setup assured that each spoke sat the same way in the jig, and even if i wanted to, i wouldn't have been able to bend it the the wrong way, only downward.






i took some measurements to be sure of how much extra bend each spoke needed, and drew a template to match the bend to. then i just gradually bent each one until it matched my template. all in all pretty simple, and worked like a charm!





i'll get some pics of the wheels up once i powder coat my rear rim.

Wow, that looks like more bend than I had envisioned, but bet it works fine. Love your jig idea. That scheme would work for increasing the first bend too with a different hole close to the edge and a little countersink and file work to radius the bend area. Nice job!