Short Commando main front fork tubes

You sir are a gentleman.

Well, talking of lowering a Commando...

https://www.ebay.co.uk/itm/Norton-C...454100?hash=item3b2c8c2b54:g:XgcAAOSwajRcfVRq

o0norton0o said:

Again, why would I take advise about handling from someone who doesn't even know how offset, rake, and trail relate to handling?? Read your own thread in the link below, where you get that relationship wrong, over and over again...

https://www.accessnorton.com/NortonCommando/steering-geometry-confirmation-bias.24310/

To the original poster Drummer99:
I apologize for calling this guy out on the erroneous comment he posted on your thread. He posts his handling voodoo so often here, I wanted to call out his mistake about how lowering the front yoke height effects trail, but he doubles and tripples down on his nonsense as you can see, and turns the question you asked in your thread into stories about himself and hyperbolic questions about his own experiences riding.

Click to expand...

So you are telling me that your bike does not tend to run wide when you back off halfway around a corner ? It does not matter what the rake and trail are doing - when you reduce the yoke offset from over 60mm to about 30mm on a Seeley which has 27 degrees of rake, you change the bike's handling from running wide to tightening it's line. With a large yoke offset, the Seeley mishandles dangerously.
As I understand it , reducing the yoke offset, increases the trail - YES ? ? ?

If increasing the yoke offset decreases the trail, try fitting the fork yokes from a garden gate or early swing-arm Norton to a Featherbed. They have loads of offset and will fit straight in without modification - you will find out what mishandling is all about.

When I posted earlier, I always had trouble working out whether the trail was increased or reduced by decreasing the yoke offset. I now accept that it is increased. Regardless, I am only interested in the effect of decreasing the offset on the fork yokes. The effect on the rake and trail only confuses the issue. But I do know this - when the front is down as when braking, the bike usually tends to go straight or run wide. When it squats, it usually turns.

Al, yes, reducing the offset will bring the forks, and thus front wheel centre line, back closer to the headstock.

Moving the front wheel centre line back, with no other changes, will indeed increase the trail.

It’s quite easy to visualise in the pic below:

Over the last 40 years, there must have been at least ten times when I have been halfway around corners running wide while holding a fist full of brakes. If you run out of road before you reach the grass, all you can do is pull the bike to the ground. If you watch any on-board video on Youtube, you will hear the guys back-off halfway around a corner. If you have got the steering geometry and rear suspension right, you are not forced to do that - you simply stay on the gas. It is something I was never aware of when I was racing regularly. Sometimes when you get blitzed when racing, you might believe the guy who did it is a superb rider - often it is the bike they are riding. With most race circuits, your speed around the corners determines your speed down the straights. If you are on the gas halfway around, you run from much further back. With my Seeley, I got it to handle by accident - not by design. I am not that smart. Which ever way you go - increase or decrease the trail, the bike will self-steer. If you go too far the wrong way, you can get serious mishandling.