Steering damper revisited

I'm going to jump in - just to offer a perspective, vis a vis riding damp'd and undamp'd modern bikes, not to disagree with the knowledgable folk on the board...

My first bike was an '83 KZ650 that I bought in 1987. My first "tank-slapper" happened just a few months later. I was convinced it was a result of the higher bars and rearward weight-bias, so I put flat bars on it and leaned over the tank as often as possible.

My second bike was a CBR600F2 that I bought in college a few years later. Had a "tank slapper" incident with it too. (Rode it 12,000 miles in 3 years as my only motorized transport - giving me plenty of opportunities for mishaps.) Come off a steel deck bridge and hit an expansion joint followed by a pothole - and had the bars ripped from my hands. No fun. Similiar "yanks" on the bars didn't end up so catastrophic, but happened often enough.

Long story short, I added a damper to the CBR - and never felt like I was going to lose an arm to a sudden pavement irregularity again. Hence, my C'do has a "proddy racer" style damper. (Bonus: Keeps the front wheel from hittin' you in the head on the lift too!)

We did a lot of our test miles on swoopy-zoomies. Once we had reliability up to a point where we could be reasonably sure we wouldn't need a works van rescue, we started going up into the Lake District.

My favorite route was M6 from Wolverhampton to Levens Bridge, then the back roads towards Barrow but diverting to Ravenglass, over the Hardknott and Wrynose passes into Ambleside, then up to Penrith, across to Scotch Corner, down the great North Road to somewhere around Nottingham and back across the Midlands to Wolverhampton. That was an 8-hour day's work, and I got paid for it!

The two prototypes didn't have either center or prop stands, which is why the production center stand grounds on vigorous cornering - we never got to test the production version! When we parked for Coke and pee breaks, we had to find a wall to lean the bike against.

In our testing at MIRA, I got a chance to compare the Commando to an Atlas on the ride and handling circuit. Based on that experience, I would categorically say that the Commando, properly fettled, handles far better than a Featherbed Atlas. Plus it doesn't delaminate your kidneys or permanently blur your vision with the vibration!

I think the Featherbed was at its best with the 500 and 600 cc Dominators. When they got to the 650SS, it was starting to get a bit marginal, and the forces involved in the 750 Atlas just overwhelmed the basic structure. Mind you, the Atlas was a sweetheart compared to the P11. What a turkey that thing was.

Not many folks realize that the P11 was never a real Norton. It was cobbled together, by a division of the Norton importer to the US, from a Matchless 500 scrambler frame with an Atlas engine and gearbox. The AMC/Norton factory didn't catch on to the purchases of engineless Matchlesses and excess Atlas engines. In the N-V research group at Wolverhampton, we suddenly got involved when a California owner sued the company for an "unsafe" motorcycle. It had a Norton badge on the tank, so he figured it was a factory bike. Apparently he'd gotten into a "tank-slapper" at 85 mph in the Mojave desert and been pitched off into a thorn bush.

I did some tests on an example that the US importer sent over - boy was it scary. At about 85 mph, it started a long-wavelength (about a 3/4 mile) yaw oscillation, which built up until you were using more than one lane on the motorway, weaving side to side. It was very difficult to control. We spent a couple of months trying to sort it, but had to give up when the company started to draw its horns in before it went bankrupt. I believe the test bike was part of the equipment sell-off at the end. It had broken glass in the tachometer where I missed when trying to hit the front fork with a hide hammer to get the pieces out for detailed analysis.

N-V was an interesting place to work, but it's no wonder the Japanese ate us for lunch.

Frank

Have you ever thought of writing a book ?

Your story- style and background make for great reading.. 8)

I agree with Stuart's book suggestion, with some period-photographs it would be a great read.

Jason

8) :lol: :lol: :lol:

But Frank we want the "first edtions" signed ~ by you the author !

All by Xmas .. well next year then :lol 8)

When questions from fellow enthusiasts trigger memories, I can give a pretty good account of things from the past. I don't think I could maintain the "stream of consciousness" necessary to write a history. Plus, it would take a lot of detailed research to make sure I got it right, and, since I'm only semi-retired and working as a part-time transit driver, I really don't have enough hours in a day to tackle something of that magnitude.

I'm happy to post things on the forum as questions arise, but a book is not really something I want to tackle. I also think it would be a problem finding a publisher for a very limited enthusiast market.

I'll continue to post reminiscences as questions pop up.

Aloha Frank. Maybe you could just tap a few lines into a journal and email a batch when you get a page or a chapter. One of these enthusiasts has to be capable of doing some desktop publishing. Pooters have changed the publishing landscape. Any desktop publishing magnates wanna volunteer?

Pooters ???

Com-pooters, 'puters, pooters.