Performance

50 mph on a good day. As for revs, not really sure but the noise it made at 50mph was enough to convince me it was flat out!

Previously james_mcneice wrote:

Can somebody tell me what top speed and Revs. to expect from my

1962 Jubilee.

Jim

About 70mph if it's in good fettle. Equates to about 7k revs I believe. Earplugs are useful.

Howard Thompson is closest to the mark. My un-tuned and well-worn Jubilee washappy toaverage 60 mph (timed) around the Goodwood circuit, meaning that it was quite clearly going faster in places ...

In new condition, the Jubilee engine develops its peak power at 8,000 rpm (!) as compared with 7,000 for the Navigator. I'll check the sums (gearing etc.) when time permits, but that should make it good for 75 mph (eardrums and dental fillings permitting) and personal experience on the road backs this up.

Sensibly, however, you should be cruising it at more like fifty, withoccasional excursions to sixty or so. Thatway, the ride will bemuchmore relaxing, and you will go a long time between rebuilds.

It is worth noting that the Jubilee's is a relatively fussy engine. The timingneeds to be spot-on, and the two cylinders making equal contributions, or it will indeed seem reluctant to exceed 50 mph. When it's properly sorted, it will seem willing ... and a rising torque curve means that 'the faster it goes, the faster it goes'. If it isn't inclined to lift its skirts and fly however, it's best not to insist. The bike will always tell you what it's happy to do ...

I hope this helps. Regards, Roger Kingsbury (Solent Branch)

Previously howard_thompson wrote:

Previously james_mcneice wrote:

Can somebody tell me what top speed and Revs. to expect from my

1962 Jubilee.

Jim

About 70mph if it's in good fettle. Equates to about 7k revs I believe. Earplugs are useful.

According to the March 1959 'Motor Cycling' road test the maximum speeds in the gears were as follows:- 1st - 23; 2nd - 52; 3rd - 65; 4th - 73.

In the absence of a rev counter and not wishing to be hit under the chin by flying pistons, I've put little red marks on the chrome speedo bezel of mine to coincide with those maxima. It provides (anything but) quiet reassurance in my many ascents of the famous 'Test Hill' at Brooklands on the bike.

Previously james_mcneice wrote:

Thanks for the info. all i need to do is find out what is wrong with mine, it seems to be unable to exceed 6000 revs. .Jim

Hi Jim... Apart from the usual suspects - timing & carburation - try fitting new valve springs. If all else is well, then maybe your valves will be snappier at opening & shutting with the new springs fitted. At least check the length of your existing ones.

Inner spring = 1.437"

Outerspring = 1.515"

enjoy!

Jim: When you are at 6000 revs, what is the indicated speed?

Have you checked that the drive and rear sprockets are standard?

Maybe a previous owner changed them up?