Bike tracks to the left.

[mydeluxe]

I assumed those were the "after" readings?

Yes, it was after I made the adjustment…Before the inclinometer on the rear tire said 89.10 degrees. Which after I subtracted it from the front reading 89.80 give me the .70 off. Now after the adjustment the rear tire reads 89.70 that leaves me with only 1/10 of 1 degree off and that was good enough for me to give the bike a try, and it rides fine. Thanks MD

 

[R_W_B]

Well I have always remembered this thread since my bike just 'barely' pulls to the left. I was glad mydeluxe got his bike running straight but I was amazed that anything inside a degree would make ANY difference, especially since the manual says as long as it's within 1 degree it's ok.

Well about a week ago I bought one of those nifty digital angle meters at H.F. like the one mydeluxe had. My old one was a needle type with only 1 full degree of readable accuarcy. So anyhow I put the bike on the lift, aimed the front straight ahead and stuck the magnetic reader on the front and then the rear brake disc.

I got a reading of 89.90 degrees on the front and 89.80 degrees on the rear. So I'm thinking that can't be worth fooling with. But my bike has always pulled a little to the left (I've got the rear alignment dead on and fall away is ok). So I sit down and do a few calculations and come up with these numbers

At 10.25" radius (20.5" dia) average inches of vertical distance
from center of axle to edge of tire (19 front tire, 17 rear)

1.0 degree of difference in vertical alignment = 0.1788962 inch (almost 6/32 inch or 3/16) (89 degrees to 90 degrees)

5 tenths (0.5) of a degree of difference in vertical alignment = 0.0894481" inch (almost 3/32 or 1 and half 16's) (89.5 degrees to 90 degrees)

1 tenth (0.1) of a degree of difference in vertical alignment = 0.01788962" inch or almost 1/64) (89.8 degrees to 89.9 degrees)

Well after looking at the calculations I can see that it is believeable that mydeluxe's 7 tenths of a degree could affect the bike. My scenario is the one on the bottom and I don't think it to be a problem since it is in fact mydeluxe's final setting.

BTW these little digital meters are really cool. It automatically shows the readout in relation to it's axis (text upside down or right side up). It magnetically sticks right to the brake disc and you can press the HOLD button and remove it and the reading stays. But then mydeluxe already covered all that back then.

Here is the link to the meter.

Digital Angle Finder / Angle Gauge

And here is a pic of it on the rear brake disc.

 

[R_W_B]

I've never really noticed my bike looking off center. In the past when I had the tank off I have checked the side edge of the backbone and it read pretty much the same as the brake discs. I will check that with my new digital meter also and get back with you later on that.

BUT here is a bit of hair splitting detail that I have decipered this morning out in the garage. I didn't have any parttime work today so I have plenty of time to fool around with the bike.

I noticed that new digital meter has an err factor of one tenth of a degee (0.01) (possibly 0.015 degrees but hard to nail that down). I also noticed that if you rotate the wheel you can have up to 0.02 degree different readings.

You also have some different readings depending on whether you put it on the brake pad area of the disc or the non rubbing flat area. So you just have to pick one and go with it (and don't move the tire afterwards till you recheck the reading after setting the vertical alignment).

You could take 3 or readings on each disc and then average them. Anyhow kinda getting the picture of why the manual says ok if withing 1 degree.

BUT . . . . I did nail down something very important fooling around this morning. And it is something I have know about and did watch out for with my old needle reader, but I got so involved with the neat 'HOLD' button on my new digital reader that I was removing it to read (for convenience) without first checking which axis it was pointing to. In other words you may read 89.7 degrees on one and 89.5 degrees on the other and think you are only 0.2 of a degree out. BUT DEPENDING ON the direction of the numbers you could be 0.8 of a degree out, a considerable amount comparatively.

Not this gets a bit complex for some to visualize to stay with me (if you want to read your meter correctly). Here is a cad depiction of the deal, and also pics of the front and rear readings of the meter. NOTICE THE DIRECTION OF THE NUMBERS ON THE METER WHILE SITTING ON THE DISC. You will notice the Front disc, the numbers are facing the right of the bike, which means the angle is coming up from the left side of the bike moving right (left axis). This is inherit into the digital meter to position the numbers in the direction of turn.

Now also notice the Rear disc, the numbers are facing the left of the bike (careful now, do a double take, see the pipes and shifter in each pic). Click each pic to maximize the window.

In looking over my figures I realized I had multiplied the 0.8 tenths in the Cad drawing by 32 instead of 16. So I corrected the Cad drawing to read ' a little more than 1/8 inch ' instead of ( a little more than 1/4 inch ) sorry. Stil same concept.

0.14311584 x 32 = 4.57970688/32's
0.14311584 x 16 = 2.28985344/16's

 

[HDDon]

Great explanition, thanks for giving all of us something to think about. Also another good reason to buy more tools.

 

[R_W_B]

A little summation here. First off I'm sure that many folks have read this and thought I have too much time on my hands or this is nit pick stuff. I can surmise this since I posted this same data on another forum, and some friends told me as much and I can rightly see their point. And I was the first to say (way back in the thread that mydeluxe's difference was too minor to cause a problem). But he said the bike rode better. And on the context of that last sentence I want to further summarize this thread's content.

(Right/Left is defined as sitting on bike)

On page one of this thread in one of mydeluxe's original post (#34)
mydeluxe's rear digital reading was 89.70
and his front digital reading was 89.80

He later verified (in post #42) that the above were 'after' finished alignment
and the bike rode better, saying that was only a tenth out.

And he then said the ORIGINAL REAR reading was 89.10 (front always stay same).

And he then said he subtracted it from the front reading 89.80 give 0.70 off.

HOWEVER...... folks look carefully at mydeluxe's meter reading number directions in post #34.

Note that,
mydeluxe's rear digital reading was 89.70 with numbers facing away the right side of bike.
and his front digital reading was 89.80 with numbers facing away the left side of bike.

This means (if you have following the Axis ramifications) that he was NOT originally out by 0.7, but originally out by 1.1 degrees. The front 89.8 takes 0.2 to get up to 90.0 and the rear 89.10 takes 0.9 to get up to 90.0 so 0.2 + 0.9 = 1.1 degrees out.

And I further submit that even though mydeluxe's adjustment corrected the bike (by his saying it road better), his final numbers of 89.7 rear and 89.8 front were STILL 0.5 degrees off (NOT 0.1 off as mydeluxe said) (no offense mydeluxe just dealing with facts here).

In other words he took 0.6 degrees out of his bad alignment and the bike even then road better. But he still had 0.5 degrees out even then by checking the AXIS NUMBER DIRECTION.

And from the improvement mydeluxe got off 0.6 degrees of improvement definitely warranted me to with my original 89.50 front facing opposite of 89.70 rear (0.8 degrees off) to try and get mine better. Which I have done but too many love bugs to ride my newly painted heat shields in till they cure a bit more, so I haven't tested the ride yet.

 

[R_W_B]

Oh and BTW so much for the Talcum powder method :lolrolling