Bone of contention

[CaptonZap]

The recent questions about centering the rear swing arm brings up a question.
If the rear wheel is not in perfect trail (centered alignment) with the front wheel, the handling will be affected.
The question is, if the rear wheel is offset to the right, what will be the effect on steering, and how much will .060 inch in offset affect the steering?

CZ

[BA80]

I don't believe there is enough room there to really make a difference in the steering. It's always best to be as accurate as possible but I've never gotten really anal about centering the swing arm but center it as best I can and never had a problem as long as the bearings are properly adjusted..

Just my $.002

[b.walker5]

Sit down with a pencil, ruler and a piece of paper. Draw a straight line on the paper. That line represents the track of the front and rear wheel in alignment. Now draw another line, parallel to the first, and offset by the amount your swing arm is. Now, imagine one line is the front wheel and one line is the back wheel, and ask yourself the question again.

How much the answer worries you is up too you.

[BA80]

Now, take your paper and figure how much difference 6/100ths of an inch makes. That'll be about the width of your pencil mark if the tip is sharp.

[TomB]

60 thou or 1.5mm, tyres aren't as accurate in manufacture as that, so I wouldn't worry about it too much, unless of course you re-align your swing arm every time you fit a new tyre.

Vmax riders wanting wider rear wheels often run 15mm offset and report no difference in handling ...personally I wouldn't do that but 1.5mm? yep.

[Crusty Snippets]

Wheels

Usually when I talk about the rear wheel following the front, I mean running a parallel path, preferably on the same track. The rear wheel can get out of alignment on bikes with chains, and when the marks on the swing arm are not notched correctly. With practice you can sight down the front wheel to the back and get it straight. With these bikes you do not have an option in that regard. And as the others have said, a small amount to one side will not effect it very much.
A story from my dad and his 16H Norton. The frame or swing arm was bent, the back wheel was on an angle vertically. On icy mornings dad would ride against the kerb. He figured with the bent wheel he was more stable and got better traction. Others could not make it up the same hill.
Unkle Crusty

[fredintoon]

- - - A story from my dad and his 16H Norton. The frame or swing arm was bent, the back wheel was on an angle vertically. On icy mornings dad would ride against the kerb. He figured with the bent wheel he was more stable and got better traction. Others could not make it up the same hill.
Unkle Crusty

Hi Crusty,
so where did your dad find a 16H with a swingarm frame?

[Crusty Snippets]

Frame

Hi Crusty,
so where did your dad find a 16H with a swingarm frame?

You guys are not supposed to be paying such close attention, or that knowledgeable.
More correctly I should have said the frame part that carries the rear wheel.
Memory tells me that was the part that was bent. And I am not sure what the correct term for it is.

Unkle Crusty

[LoHo]

Aww, c'mon Fred...take a page from our media outlets and don't let several facts ruin a great story.

[fredintoon]

You guys are not supposed to be paying such close attention, or that knowledgeable.
More correctly I should have said the frame part that carries the rear wheel.
Memory tells me that was the part that was bent. And I am not sure what the correct term for it is.

Unkle Crusty

Hi Crusty,
used to own a 16H, didn't I? As I remember, Norton put tele-forks on the 16H in 1946 and stopped production in 1954.
In the last years of production you could get a plunger frame as an extra-cost option.
I'm not sure you'd be correct in calling the back end of a rigid frame a "subframe" unless it bolted off, so "the back part of the frame" is a good a term as any.
But I doubt that a canted rear wheel was why your dad's 16H gripped better than his contemporaries bikes, more likely it was his superior riding skills.

[Crusty Snippets]

Early bikes

For me the early bikes are what I remember seeing. So that goes back to the fifties, and mostly road race bikes. All had rear suspension.
For the NZ guys I use to watch Peter Murphy and many others race in Mangere.
So when I recount a story from my dad, I have to change gear and go back to the thirties, which means the history books.
My dad likely rode a bike until 1948 when we left London and headed to NZ.
It would be a used older bike he rode.
And you are correct. The frame twist would have no effect on traction, but it was a good story to chat about. Right up there with mirrors on bikes.

First bike I rode was probably a 350 Triumph side valve. A guy down the street had a rear sprung hub Triumph, that was a neat bike. The " bath tub " Triumphs were also about.
At the races I went with Forest and Barry Cardon who had Nortons.
This is stretching the memory.

Unkle Crusty

[skids]

Usually when I talk about the rear wheel following the front, I mean running a parallel path, preferably on the same track. The rear wheel can get out of alignment on bikes with chains, and when the marks on the swing arm are not notched correctly. With practice you can sight down the front wheel to the back and get it straight. With these bikes you do not have an option in that regard. And as the others have said, a small amount to one side will not effect it very much.
A story from my dad and his 16H Norton. The frame or swing arm was bent, the back wheel was on an angle vertically. On icy mornings dad would ride against the kerb. He figured with the bent wheel he was more stable and got better traction. Others could not make it up the same hill.
Unkle Crusty

That is crazy! But if it worked, how can you argue with success?

[Schming]

That is crazy! But if it worked, how can you argue with success?

Riding against the curb keeps the bike from sliding out and gives traction to the sidewall.

[skids]

Riding against the curb keeps the bike from sliding out and gives traction to the sidewall.

I was going to say that there is no damn way I could stay in control, but there are better riders than me.

[LoHo]

Another often overlooked factor is that fathers often give the appearance of having a handle on things when they are really out on their asses with a voice in their heads yelling "Don't f*** up, don't f*** up, don't f*** up!" I think of some of the stuff I did with my dad that were right on the verge of disaster, but all turned out well. As a father of sons, I can testify that this is a generational phenomenon. Now my grown sons will say something like, "Hey, remember when dad took us to ... and we...." My wife will listen and turn on me with, "You took them WHERE?!"