Norton P-11 page 3 Next P-11
Here is a real surprise item in the carburetion department, Keihin CR's! These wonderful items, first seen on factory Honda road racers, really work about as well as it seems possible for a slide valve carb to work. At the time these were aquired, jets weren't available (details....) so new jet blocks were fashioned to use Mikuni main jets! These have mechanical linkage much like that on the old single cam 750 Hondas, except with a tiny caged ball bearing on each side of the bell crank in each carb! The hardchromed slides, in stark contrast to AMAL experience, hardly needed any return spring at all, making the throttle effortless to open up and hold open. Of course the Keihin carbs are also rubber mounted, in standard Japanese fashion (they really got it over on the Brits with that one). The fuel filters were big enough that they added miles to the fuel tank range!
The front brake rotor is stock Norton, an early iron one, with .50 caliber holes in it. Although the hole diameter is larger than conventional practice would suggest, this machine braked very well; so well, in fact, that it wore out the fork slider on the side mounting the caliper!
The lesson from that is that a sturdy fork brace, which does not bind or restrict slider travel, is a practical necessity for a single front disk brake unless you want a worn out slider and the consequential front wheel cocking under braking! Yamaha RD-350 pads, by the way, can be trimmed down slightly and will fit if you have trouble finding Norton pads (they're a lot cheaper too).
Probably what made the front brake work so well was installation of a GriMeCa 13mm piston front master cylinder. The increased line pressure from this unit made it possible to bottom the front forks ka bang bang if you grabbed 'holt of it hard enough (kids don't try this at home).
Since it is nearly impossible to over rev a Norton (at least in 3rd or 4th gear where it really counts), instruments were not used. The mirror was tucked under the handlebar, so you can't get snagged on it in the event of an unscheduled excursion over the handlebars.
Other modifications are minimal and mostly straightforward; rear fender is a narrow alloy one, and the seat was an aftermarket item (originals were missing).
The minimalist and inexpensive plastic front fender is what you might call a mud scraper. The sharp folks who made them labelled it "Muder".
The tailight and housing combination are fairly visible here, a small alloy housing holding the early style Lucas stop lamp. Another Hot Rod P-11, click here for Page