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Strife said:
i saw the pictures, i followed the instructions, but i still feel a slight wobble coming from the rear wheel. I reset the strings a couple times and reset the rear wheel to match what the instructions said to do but with various chain tension. I still feel it every time. I just wanna make sure that I'm 100% correctly doing it right. maybe I'm missing something...
Your string is taped to the lower rear of the wheel and the strings are just barely touching the front edge of the rear wheel? What you're doing is you're extrapolating the travel of the wheel. If the wheel is 4" wide, those strings are going to be 4" apart along their whole length, and will be pointing exactly in the direction the rear wheel is pointing.

Basically, your front rim should be the same distance from the string on either side, or within a small amount of error. It sounds like you did it correctly.

If you confirm that the distance is equal, your wobble could be from a poorly balanced wheel, unless there's some kind of problem with your axle. How bad is the wobble?

Strife said:
That's the same exact test, in theory, except FOG's test includes those jackstands because attempting to hold the string while laying down on the ground and eyeballing it is pretty... dumb.
 

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Pogo said:
If you confirm that the distance is equal, your wobble could be from a poorly balanced wheel, unless there's some kind of problem with your axle. How bad is the wobble?
It's not horrible, but it's enough that I don't feel real comfortable while riding...
 
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Strife said:
Pogo said:
If you confirm that the distance is equal, your wobble could be from a poorly balanced wheel, unless there's some kind of problem with your axle. How bad is the wobble?
It's not horrible, but it's enough that I don't feel real comfortable while riding...
Well does it feel like a constant bumping? Or does your tail actually swing back and forth slowly?

I think I'll refrain from suggesting anything else. There could be some other serious reason for a rear wheel wobble. Wait for more experienced input.
 

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Printing from an HTML page never comes out looking like it did on the website. Here is a pdf of "The String Thing".

By the way Fog, I very much appreciate guys like you that will take the time to put thier knowledge on paper where those of us who do not have that experience can access it whenever we need it. It is guys like you that actually make the forum thing work, otherwise we'd have a chatroom full of kids. What you wrote makes completely logical sense, will be very simple to do if you have much mechanical ability at all, but I would not have come up with it on my own. And best of all, it was free.
 

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This is the next thing to do on my list....

My Haynes manual has a variation on the String Thing but only if you have two lengths of perfectly straight metal or wood (which most people don't in the right length) lay them along the rear wheel either side pointing them forward and past the front wheel and measure the distance from the rim of the front wheel to each nearest straight edge. String sounds a little more accurate though to be honest plus you're not dealing with abnormalities in tire width.
 

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I just did the string thing to my bike, felt kinda like I was just moving the strings to match the tire rather than the other way around? I had a harder time with the front tire getting it to touch on all four points seemed like the jack stands would go close enough together.

When I finished it looked to be alighned and the little line on the axle lined up on both sides with the lines on the swing arm so I hopefully its straight, both are on the 3rd line etc.

Its probably being to knit picky, I was looking for a clear indication that the wheel is in alighnment, but with this method you pretty much just make a judgement on the string being straight and touching on all four points.

I'll have to wait until the foot of snow on the road clears in spring and feel how it rides.
 
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You should only have to move the stands once each time. You're not moving the strings to match the front, you are only wanting to look at the distance between each front tire wall from its respective string after the strings are just barely touching the front half tire wall of the rear tire.

This method is very accurate and FOG allows such a seemingly wide margin of error in the distances from the front wheel because of how projecting a line from a very small angle (the angle of misalignment of the rear wheel) will quickly extrapolate into a noticeable difference after several feet. Compare his margin of error with how the rear swingarm markers drastically change angle after being moved fractions of a millimeter and you'll know what I mean.

I think the harder part is making sure your front wheel is turned perfectly straight so that you can accurately judge the distances, otherwise when turning the front wheel you end up also turning the whole bike very minutely which can throw your measurement off. Of course, the strings are straight so it shouldn't be hard to set the strings up roughly, and then turn the wheel a small amount while observing from a top-down view to judge if the front wheel is straight before making the final adjustments on the strings to touch the four rear wheel points.
 

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Discussion Starter #68
Whoa!! Several missunderstandings here. The strings must be re adjusted every time you move the rear adjusters. They are to touch the rear tire very lightly at the front edge. they will never touch the front tire anywhere. The strings are there to show you the path that the rear tire is aimed at and will follow. The idea is to make this path be central to the front steering axis as shown by the front tire. Set the front wheel a straight (parallel) to the strings and measure from them to the rim to check if the rear is pointed to it's center.

FOG
 

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I spent about 5 minutes trying to get both tires touching at 4 points before coming back down and seeing in the picture the string doesn't even touch the front tire haha. Dumb moment

After you do the string thing, is it uncommon for the lines on the swing arm not to match up as well?

After I set the rear wheel where it looked straight I also checked the lines on the swing arm and it also matched on both sides.

So hopefully I did it right, I'll find out sooner or later.

Now that you explained it in that last post it makes a lot more sense

Thanks!
 

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so i was telling my uncle who is a motorcycle guru about my 2 hrs playing around with this idea for alignment and he looked at my bike and said "i just use the notches on the bolts and make sure they are at the same spot on each side"

it seems that the plates on there were designed for that exact purpose. my question; is that what thye are there for? and if they are are whats the difference or point in using this idea?
 
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darkrangr said:
so i was telling my uncle who is a motorcycle guru about my 2 hrs playing around with this idea for alignment and he looked at my bike and said "i just use the notches on the bolts and make sure they are at the same spot on each side"

it seems that the plates on there were designed for that exact purpose. my question; is that what thye are there for? and if they are are whats the difference or point in using this idea?
They can be accurate. However, it's common that one or both of those sliders move by several millimeters when they're not tightened down by the axle nuts. If you can keep them in the same spot (say, making sure they're both slid "backwards" when you're tightening the castle nut and opposite bolt), then yeah, you can align it that way.

But you always check with the string thing afterward. Fractions of a millimeter off on those sliders results in several centimeters when you extrapolate the path of the rear wheel forwards.
 

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So after a chain adjustment I did the string thing. The whole thing took a huge amount of time as I am mechanically disinclined. Still, I finally got the chain right and the wheels appear to be aligned with the string as a guide, but...

they don't LOOK aligned. Certainly look crooked when looking at the rear wheel vis a vis the centerstand. And the axle marks are off about half a notch, at least. I'm only worried because I had a lot of trouble with the strings, that I might have somehow not gotten it right.

I took it out today, and noticed no problems; when letting go of the bars, the bike continues on the straight and narrow. Is this a fair indication that my alignment is not out of whack?
 
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I would make sure again with the string thing, because it's common for the wheel to shift backwards when torquing the castle nut. To prevent this, you just hold the bar vertically and push forward to torque it (with the front brake rubberbanded or tied to the handle to prevent the bike from moving off the stand).

My right marker plate moves several millimeters and is not an accurate indication of alignment unless it is held towards the butt of the swingarm while torquing, which is why I only use it as a preliminary guide before tightening a little, doing the string thing, finishing the torquing, and then checking the strings again.
 

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Thanks. I had the brake applied when I torqued it, but because of the length of the wrench, the only way to torque it was lifting up from the bottom (from 7 o'clock to 11 or so looking at the castle nut). I can always find a extender if I need to. I think I'm going to get a laser pointer and recheck it with that like was pointed out on page one.
 
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Well, you can torque it from another direction, but you just have to make sure your plates (particularly the right one) are still snug against the swingarm. After adjustment, they can only move outward, not inward, due to the adjusting nuts.
 

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Pogo said:
Well, you can torque it from another direction, but you just have to make sure your plates (particularly the right one) are still snug against the swingarm. After adjustment, they can only move outward, not inward, due to the adjusting nuts.
ooooh, the butt plate things? Ok I can check that while I still have the wrench tonight.
 

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No one has posted in a few months but I just wanted to express just how helpful this thread was.

Just did my horizontal alignment last night after a few days of trying, I finally got it close enough where the rear wheel was pointing in the right direction. Before the alignment the rear wheel was pointing so far to the right that I couldn't even get the string on without touching something (measured like 1.5 inches on one side, like .5 inches on the other, from rear tire to swingarm).

Now the bike rides like a champ with minimal vibration. I just wanted to say it was so worth it. You can totally feel the difference and its a huge difference.

After all that time spent trial and error style, I can adjust the chain and align it with my eyes closed. Thanks FOG you rock.

Oh and I haven't tried that vertical alignment yet or the rocking the fork or something like that. Another task for another day/week. ;D
 

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Oh one other thing, I'm not completely sure but I remember the sprocket was all the way on the inside of the chain, like rubbing it. Now after the alignment it's in the center of the chain.
 

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It seems like I have the same issue as a couple of other people, where the front/rear axles are parallel (there is the same distance between the string and the 'front of front tire' and 'rear of front tire' on the left side and on the right side), however the wheels are not centered on the same line (measurements on the right side are less than on the left side). Even though this is the case, I don't feel any wobble when letting go of handle bars for a bit.

When someone asked about this same issue, Pogo quoted FOG's original instructions saying to "adjust the rear wheel chain adjusters to correct the error." I have read the instructions for the string thing several times and am unclear about what the chain adjusters are. First time reading the instructions I figured that FOG was talking about the axle adjuster nuts that move the rear axle...but now I'm not so sure.

I thought that tightening/loosening the axle adjuster nuts moved the corresponding ends of the rear axle back and forth along the swing-arm and that their proper adjustment meant that the rear axle is parallel to the front axle. But they don't seem to do anything to actually move the wheel from side to side.

Could someone please provide clarification?

Thank you.
 
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