Did my first wheel build

Was very pleased with myself and told the wife, she just chuckled and said... "what next, fire?"

Seriously, i used a one cross / underlaced pattern , 13 guage sapim spokes on a mavic EX729 heavy duty mtb rim with a bpm 8fun motor.

I thought that my initial set up for adding spokes was worth a mention. I used a car tyre from a 17" wheel to hold the rim and a stiff cardboard box with space inside for axles to support weight of motor. Infact the box was the one that the motor came in.




I was apprehensive at the start and it did take a few hours in total, but it wa one of the most satisfying things i have done bike building. I used 190mm spokes.
There were two errors i made. One was lacing the spokes which did not leave the maximum amount of space to attach pump to a valve, but there is enough room.
Two, i could have ordered 1 or 2mm shorter spokes for the left hand side as the bpm motor is 5mm out of centre. I decided that loosening one side and over tightening the other side to 'dish' the motor and rim was not for me. I would rather the spokes are done to fairly equal tension.

By the way, i painted my motor black to go with black spokes and the rest of my bike. Yes i know NOW you can get black bpm's I used a special metal primer and hammerite smooth in a spray can. Lets hope it does not help to retain heat.

Any thoughts on any of the above?

Andrew

Takes a lot of self confidence to tackle this job, but very rewarding.

Mine was a 20" 9-C with piss poor spokes with loose threads and they slipped out after only a few weeks of use. So i changed them over to good quality spokes and all is well after many years of riding.

Most of the time i am a bit of a cheap arse when it comes buying bits n bobs, though this time i tried to live by the motto that i say to others.... "Do it once, do it properly"


I would just like to say at this point that i have not tried riding on the wheel yet. :lol:

Just last winter done my first wheel and had the same error for the valve but after 3 times redoing it i got it right. The only thing i need now to build is truing stands with some gauge meters, would be nice.

Tire valve has gotten a few before. Lacing really isn't that hard and it's very easy to practice on scrap wheels too which leads to more improved skills.

Crazy thing for me is that since I rebuilt with good parts I really haven't done it again going on a year or more. I needs some practice soon!

I've built three wheels now, all in the last couple of months. For years I fought shy of doing it, but after doing the first one (following the great instructions on the late Sheldon Brown's web site) I really don't know why I didn't have a go at doing it before.

I found that a stand to hold things whilst lacing the rim and hub up wasn't really needed, I just put the hub between my knees and rest the rim on top. Once all the trailing spokes are in it's fairly easy to handle. My truing stand is just some glued up bits of wood, to which I clamp a DTI to get things trued up.

The last wheel build, done last weekend, was a dished 20" rear wheel with a Q100 motor. Turned out reasonably well, although the tension on the dished (freewheel) side of the wheel is noticeably greater than that on the other side. I doubt this will be a problem, as the late Sheldon Brown seems to suggest that this is normally the case.

I will definitely be building my own wheels in the future. Taking time to true the rim vertically and laterally was enjoyable, you really get a feel for it. I used zip ties to help true the rim.

I took mine for truing to a shop and boy they did a shitty job there. I had to re true it myself. One thing is to put few miles on a wheel and tighten up again. It isn't that difficult as it looks. More difficult to calculate and then source spokes to specific motor and rim.

I like your setup. uncomplicated and gets the job done.

My setup is similar, using parts of shipping padding. For the hub, I use the 2 round axle protection polystyrene pieces stacked sitting on a plastic lazy susan (99 cent store). The rim is held up by whatever boxes I have lying around that will add up to the right height. The lazy susan was added recently and it helped speed up the lacing just a bit as I did not have to re-position myself nor the setup.

Don't mind the messed up spoke arrangement here, it was redone as this was just a test of the setup



BTW, dishing requires difference in tension, NOT different lengths of spoke. The different lengths of spoke will ALLOW you to set the tension difference and keep the spokes consistently seated in the nipples instead of half of them sticking out further.

Congrats, knowing how to build and true your own wheels is very useful knowledge to have with this addiction. I have trued wheels since I was a kid figured it out on my own with the, tried and true, trial and error method. Never had a reason to build up a complete wheel until lately. Like you I forget to start half of them out right and end up with the valve stem in a place other than I would like it to be. Every time I go to build another I tell myself I am going to do it right this time. But I have oldtimers so I have trouble holding a thought long enough to take any kind of action most days so I am usually just happy to get the thing put together in the end ;^)

Thanks for all the feed back guys, its nice to know i'm not alone in these mad pursuits

Great work, but i don't think it's finished yet. Have you checked that the rim is central to your frame. Normally it isn't with the BPM motor, so you have to do a bit of dishing, which is easy enough. You just go round the rim and loosen every spoke on one side by half a turn and then the other side tightening a half a turn, Don't lose count and don't lose your place otherwise you'll be truing it again, and it's also easy to forget which way to turn to tighten. Good luck!

d8veh said:

Great work, but i don't think it's finished yet. Have you checked that the rim is central to your frame. Normally it isn't with the BPM motor, so you have to do a bit of dishing, which is easy enough. You just go round the rim and loosen every spoke on one side by half a turn and then the other side tightening a half a turn, Don't lose count and don't lose your place otherwise you'll be truing it again, and it's also easy to forget which way to turn to tighten. Good luck!

Click to expand...

Hiya Dave. Yes you are correct, i finished truing the rim to find it was 4 or 5 mm's out of centre. I realised this would be the case when initially measuring the motor dimensions to work out spoke lengths. IIRC..There is a 10mm difference measuring between the flange and hub edge on either side of the motor.

I decided not to loosen and tighten either side of the rim as i would prefer the spokes to be under similar tension, though thinking about it once there is a load on the rim the tension will be unequal. I will see how it goes for now and will keep checking the spokes.

Finally, the wheel itself has ended up centred very well in the bike frame, though this is due to having to pull the non drive side dropout out with 10mm of spacers to allow for my beefy hydraulic brake calliper. And before you ask, yes it is a steel frame, and it has horizontal dropouts.

Thank the lord for steel and slot drop outs!

I can highly recommend these frames if you are on the lookout for something that really ticks the boxes for a mtb-e build..... http://www.on-one.co.uk/i/q/FROOSD1226/on_one_inbred_26er_slot_dropout
I have two of them one 16" and one 20"

Andrew

When you dish the wheel by loosening the spokes on one side, the rim moves until the tension on both sides is equal. The same happens when you tighten the spokes on the otherside. When it's dished, all spokes will have equal tension.

d8veh said:

When you dish the wheel by loosening the spokes on one side, the rim moves until the tension on both sides is equal. The same happens when you tighten the spokes on the otherside. When it's dished, all spokes will have equal tension.

Click to expand...

This is not correct. It is difference in tension that allows the dishing. If tension is equal, it will pull equally on both sides, which means no dish (rim will sit evenly between the flanges). Its like tug o war when both sides are equally strong. Nothing budges.

cal3thousand said:

d8veh said:

When you dish the wheel by loosening the spokes on one side, the rim moves until the tension on both sides is equal. The same happens when you tighten the spokes on the otherside. When it's dished, all spokes will have equal tension.

Click to expand...

This is not correct. It is difference in tension that allows the dishing. If tension is equal, it will pull equally on both sides, which means no dish (rim will sit evenly between the flanges). Its like tug o war when both sides are equally strong. Nothing budges.

Click to expand...

You said it yourself in the last sentence: If one side pulls harder than the other, the rim moves until they both pull the same. It's not possible to have more tension on one side than the other.

So if my rim is 4-5mm out of centre to the hub will it affect structural strength much or the revolution of the wheel.. Do i have to worry about t?

brumbrum said:

So if my rim is 4-5mm out of centre to the hub will it affect structural strength much or the revolution of the wheel.. Do i have to worry about t?

Click to expand...

You don't have to worry about anything wth your wheel dished. Nearly all my motors are dished, and I've done 4 BPMs without any problems. My main BPM commuter has done more than 3000 miles like it and I've never had any trouble with rims or spokes and I use the cheapest BMSBattery ones.

Running with your wheels out of line won't do any harm, but you can get handling problems. The bike won't steer as well when you're leant right over.

I too just did my first wheel build. I did a BPM CST into an older mtb rim. I ordered spokes for single cross with 1mm long for one side and 1mm short for the other for dishing.

First attempt I alternated spoke head direction but since it's a rim brake setup this did not dish it enough so I changed it so all the spoke heads face the same way. It now is centered and I was able to true it nicely. I haven't ridden it yet as I'm waiting for parts but I suspect it will need tweaking afterwards.

Gary