Truing Up Rims

[boppinbob]

Going too fast as usual I hit a pothole, didn't blow my tire, break any spokes, or crack the rim but it is out of true. I don't have a truing jig. Should I try to use the brake calipers and try and true it myself (there is a right to left wobble in one place). Or should I have it professionally done if they will even mess with a rim with a hub motor in it. BTW a truing jig is about 200 greenback. UPDATE: Just went to youtube and saw a good instructional vid. I think I'll try it myself first using the brake calipers first.

 

[Ypedal]

No need for specialty tools.. use the frame and brake pads as guides....

 

[e-beach]

It depends how good a mechanic you are.

I am lucky to have a self help bike repair place walking distance from my house. Every thing I need plus help for $7 an hour USD.

When I go there to true a rim they don't have us get the rim perfectly centered in the truing fork, they have us pick either the left side or right side an just go with that. So it is possible to just use your v-break pads (if you got v-breaks) to get your rim trued, but you may also need a dish tool to check the dish of your rim.

http://www.jimlangley.net/wrench/truingstand_parkdish.jpg

Also there are some tricks.

Before you start to true the rim, take if off and lay it down flat on the floor with the axle touching the floor. Gently press down on the rim with both hands 180 degrees apart. You should hear the rim creek a little. Spin the rim in your hands and repeat at a few different locations. You are trying to get the rim to release into its most stress relieved position before you start. Don't tweek the rim, just press on it a bit to get the spokes to be where they want to be.

Using a good spoke wrench, only turn the spoke nibs 1/4 to 1/2 turn at a time. This will keep you out of trouble.

Also, there are plenty of youtube vids to show you how to do it. Once you watch a few, then you can decide it you want to save the money or give it a go yourself.

Just remember, truing takes patients so don't do it if you get "all nervoed" easily.

Here is a youtube video to start you out.

http://www.youtube.com/watch?v=a25vC5zsf6A

 

[biohazardman]

I just tape a pencil to the frame with the eraser close to the rim. Good advise givien about the 1/4-1/2 turn at a time. Remember tightening in the normal since clockwise is loosening the spokes as you are working from the other side of the nipple. First loosen the bulged out spokes, I do them one at a time, then tighten the side you are pulling the rim to. Spin the wheel around and do it again. Sometimes you chase the bend around the rim a bit before you get it all. Just remember to loosen and tighten evenly to avoid vertical flat spots in yer rim.

 

[manitu]

All good advice here.

Instead of using the brake-pads , you can use plastic strips , like this:

Another thing to remember, if your wheel is to stay true the spokes need to be straight , with no twist. Twisted spokes will rotate and unscrew or stretch.
This depends on the spoke , and heavier spokes twist less than the usual bike stuff.v Anyway , on normal bike spokes , you usually tighten 1/4 turn extra , then loosen 1/4 turn , to remove the twist.
On my radial laced HT with 26" wheel and 12g Sapim spokes , I used about 1/8 turn.

.manitu

 

[dogman dan]

The zip tie trick for the win. Find the still straight part of the rim, and cut the zip tie to just barely not touch at that point.

Turn spoke nipples only 1/4 turn at a time. Keep going round and round till you have it straight enough. Take your time, using the aid you need. For some it's beer, for others it's calm music, whatever helps you slow down, focus and get patient. It might help to go ride around the block about half way through the process, to help the wheel settle in to it's new adjustment.


If the rim is really damaged, you can't really get it right again ever. You'll run out of threads the tight side, despite spokes that are crazy loose on the other side. But if you can just get it tolreable to ride, you can live with it for awhile, till you decide what to do about it. You can live with quite a wobble if your bike is disk brake.

 

[boppinbob]

Another delay but easily fixable. I only have spoke wrenches sw 0 thru 2 for a time when I was a pedal biker. The rear spokes are a larger gage so I need a .156 wrench which should be a sw-3. If I can't find a sw-3 I'll have to pull out the dremel tool and make it an sw-3. or use a small wrench. So ebikers out there take inventory of your tools.

 

[Ypedal]

I dremelled out a park tools tool for the 12g spokes.. a must have item.

 

[Ykick]

Another delay but easily fixable. I only have spoke wrenches sw 0 thru 2 for a time when I was a pedal biker. The rear spokes are a larger gage so I need a .156 wrench which should be a sw-3. If I can't find a sw-3 I'll have to pull out the dremel tool and make it an sw-3. or use a small wrench. So ebikers out there take inventory of your tools.

Another bonus with single butted 13/14ga spokes is that more common spokes wrenches will work.

It's often hard to tell how much damage is/was actually inflicted when hitting holes. My couple experiences have been a slight flattening of the rim at point of impact. Sometimes, awfully hard to see and another problem is that the tire bead is often damaged at that point and will eventually separate thus allowing the tube to poke through and pinch/cut after a few miles back in service.

Big plus on the wire tie wraps!

 

[dogman dan]

The multi size spoke wrenches tend to have a size that fits motor wheels good enough. #13 if I remember it right. Bear in mind, chinese nipples are going to be a certain size, more or less. :lol:

 

[boppinbob]

The good news is I've finished truing the wheel so it doesn't rub the calipers and is actually pretty straight. The bad news is during truing I found a flat spot and the start of a cracked rim. I'm going to order a double wall 36 spoke 26" rim and a hookworm tire and try and lace it myself since I've got new found confidence in truing.
Ypedal has a good vid out on lacing a hub motor into a rim.

Ypedal's vid --->http://www.youtube.com/watch?v=7-QZazAY0cc&list=UUJCgYcCXBAuxEgVT1bpMnyQ&index=17&feature=plcp

and here is the best truing vid I've found

[youtube]a25vC5zsf6A[/youtube]

 

[Ykick]

Use an eyelet rim and 13/14ga butted spokes.

 

[amberwolf]

It's often hard to tell how much damage is/was actually inflicted when hitting holes.

My most common problem is spokes damaged at the head but not yet broken, and I can't see the problem until they finally break (usually several at a time). Sometimes one of them breaks at the original impact or shortly after during the remainder of the ride, if I have heavy cargo in the pods.

But usually the rim itself is bent enough sideways to be problematic in re-truing whether or not a spoke breaks. My current rear wheel has just about had it (I think it might be the fifth or sixth one I've gone thru on CrazyBike2 in the last 3000+ miles).

 

[dogman dan]

Between issues like that, and my back problems, I simply insist on full suspension. Unless you frock up a curb hop or run into a huge pothole, you never break spokes or bend rims.

Get going on your full suspension longtail AW. I just love the ride on mine.

 

[Ykick]

Between issues like that, and my back problems, I simply insist on full suspension. Unless you frock up a curb hop or run into a huge pothole, you never break spokes or bend rims.

Last Fall the good city of New York decided to rework pavement around every manhole cover along 57th St which involved cutting 6' square of pavement around each manhole going down roughly 3-4". Trouble is, the cutting crew would do their thing and just leave the site with no cones, flags or signage for days waiting for the paving crew.

Well, I hit one of those sections at 25MPH and even with FS it flattened my rim and ripped a spoke from the rim. If it had been non-sus I would've wrecked.

Put that bike out of commission for a month hassling with spokes and new rim. Fortunately, it was a good opportunity to upgrade the rim to the same Mammoth Fat already used on the front and I went with quality single butted spokes. The new wheel is better than ever and might survive the same shot that destroyed the Chinese rim but I would rather not test it.

So yes, FS will help a ton and might even make the difference between staying upright or going down but leave it to taxpayer dollars to do what you'd think would be impossible.

 

[Brentis]

The good news is I've finished truing the wheel so it doesn't rub the calipers and is actually pretty straight. The bad news is during truing I found a flat spot and the start of a cracked rim. I'm going to order a double wall 36 spoke 26" rim and a hookworm tire and try and lace it myself since I've got new found confidence in truing.
Ypedal has a good vid out on lacing a hub motor into a rim.

Ypedal's vid --->http://www.youtube.com/watch?v=7-QZazAY0cc&list=UUJCgYcCXBAuxEgVT1bpMnyQ&index=17&feature=plcp

and here is the best truing vid I've found

[youtube]a25vC5zsf6A[/youtube]

Looks to me,a perfect time to wrap that motor in a 20" rim.
The change in characteristics will shock you.
Automotive grade torque. :wink: (more than my first car)

A comparison for your consideration.

Your current setup.


Your potential wheelie/burnout machine.


*You lose 3 mph on the top end.
*Install/ride requires extra considerations.
*Gain 22 foot-lbs torque.
*3.5% efficiency gain. As shown in wh/mile consumption & overheat time.


I can do brake lock burnouts & if balanced right, Wheelie.
That's @ 52v nom.
Consider it.
Join the Darkside young Jedi.

 

[boppinbob]

Looks to me,a perfect time to wrap that motor in a 20" rim.

My electric motorcycle will have 17 or 18 inch wheels...