Riding RPM

Scout63 said:

I ride in constant fear of things popping out in front of me and rarely exceed 50 mph. Cape Cod has the perfect storm of danger- very old population, sand on roads, clueless tourists and frustrated locals. Racing is out since the nearest track is probably Connecticut or New Hampshire. BUT - I need to ride like I need to breathe.

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I hear you on need to ride , there is a road course 20 minutes from my house , I go there occasionally as a spectator only .... Nova Scotia has oldest population as a group in Canada , so nice here no one wants to leave , if they do they almost always return to retire, relax or go crazy ....

Around here a lot of people don't even stop coming out of their driveway, mostly they just don't look. Not expecting anyone to be on the road. I can't tell you how many times it's happened to me in the car as well as the MC. When I see them, I'm very leery. Then there's the A-holes that drive in the middle of the road because it's not marked about 20mph under the speed limit which is usually 45. Then they get pissed because you find a place to pass. There's a lot of country self loathing here, wife beaters and dog kickers. I actually think the US is getting worse that way. rant over.

DogT .... same kinda thing happens here , especially as you travel farther from town , some of those guys have been pulling out of their yards, hay fields or woods roads for 50 yrs or more and just don’t bother looking as never anyone coming , I get upset when riding with others when they start lagging behind start to worry the guy I saw coming in his old truck is not thinking oh yeah prolly more bikes behind that one , as result I find myself out solo way more as I age ...

Rolling out on the dual carriage is boring but then it is a fairly safe place actually. A lot safer than the B roads with the acursed bicyclist and horse riders. The incomers, well they aren't used to non-suburban driving.

We get a plethora of bicyclists from the city out here in huge groups. Then they take up the 50mph double lane road and there's no shoulder and nary a passing zone. They have their own parks for that, it's really dangerous here with all the hills and curves. I think it's plain crazy to bicycle on these country roads. At least the MC can keep up the speed.

In about 1962, I was walking with a friend along a main road. We came across an ambulance where there was a motorcyclist dying by the side of the road. A car had backed out of a driveway in front of him. When he hit it, his foot went behind the car's rear bumper, and he was pulled down onto the road. His head injury was so bad, that he could not be moved. We walked past without looking see if we knew the guy. The next day a couple of his mates came around, and it turned out that we knew the deceased very well. In those days we used to hoon around like maniacs and that young guy who got killed might have been trying to copy us.
I suggest we all need to be careful about the example we set. With motorcycles, what you see is not necessarily what you get.

... don't know if anyone's noticed but only 2 of the last 20ish posts have anything to do with the thread subject

I know... Wandering old minds. Anyway in my uneducated opinion for just straight forward everyday street/short haul road riding on an 850 the 20T is pretty much hard to beat. In town only I'd probably enjoy a 19T a tad more with the stop/go being more frequent, but the 20 handles it all for me well enough.

I’ve had both a 72 Combat and a 73 850. I loved the 19 tooth geared 750, that thing loved to rev, with its high compression and cam. The revs the OP hits seem very right but two caveats, 6000 rpm on an engine with only 400 miles may be pushing the breakin a bit, and please remember, the 72 had a one year only misdesign of the crankcase scavenging and breathing systems and if unmodified, sustained high rpms can sump the entire contents of the oil tank into the crankcase. I will never forget rolling pretty hard back to LA from the San Jose Mile many years ago and discovering the oil tank was empty, due to sumping (and increased oil consumption from the high revs). Be aware of this, and the fixes you may want to make at some point. Varying revs will keep it at bay in the meantime.

To continue to answer the OP’s question, in contrast, my 850 is much torquier and revs much slower, more lazy and laid back feeling, and its 20 tooth is good for most non-highway riding, 21 for highway only.

The break in procedure for a new motor is specified in the rider's manual. The OP would be well advised to heed it.

I think we've given him what he wanted to know. The final drive v.s. rpm and road speed depend entirely on your riding style and the roads you travel.

Every motorcyclist needs two motorcycles - one for commuting, the other for thrashing. The gearing for each is entirely different. For commuting a wide ratio box and low overall gearing is good. For thrashing, a close ratio box and high overall gearing is good. If you improve your motor's torque output, you don't often feel any benefit until you raise the overall gearing. So in effect - if you only have one motorcycle, you need to make a decision, there is not much room for compromise.
In my own situation, I only ever ride on short tight race circuits and my overall gearing is absurdly high, but my gearbox internal ratios are now six and very closely spaced. I ride the very top of the torque curve and use the gears to climb. Acceleration is much faster with close ratio gears, regardless of the overall gearing. But high overall gearing is better than low. You need to keep a Commando engine pulling hard if you want to go fast. When you race a Commando engine, where you get passed should be near the very end of the longest straights on the circuit.

Sounds like a 20 Tooth is what you are after. My 72 loved rev. time , but at my age I sank into the 76 850 .

Until I raced my Seeley 850, I always believed that lowering the overall gearing makes the bike accelerate faster. However a lot depends on the torque characteristic of the motor. With widely spaced internal gearbox ratios, you lose more revs on the up-changes, so the motor has more ground to make up to get nearer to it's peak. So closer ratios are important. A Commando engine does not spin up quick on the throttle, because of the heavy crank. But if it is spinning high and you race-change up a gear, you lose almost nothing because of the crank's inertia, regardless of how high your overall gearing might be.
Gearing a road bike is the same as gearing a race bike, except that you have to cater for the situation where you ride in heavy traffic.
There is an easy answer - you buy the American racing close ratio cluster and fit the Commando first gear. Then raise the overall gearing one tooth more on the countershaft sprocket. First and second gears would be adequate for slow situations, and you would have the good top three gears. - $700.

I once tried to race with the standard Commando gearbox - it was impossible - too slow everywhere. It might be OK on a road bike, but there are much better options.
The same thing happened with the BSA Gold Star. The standard box was replaced with the RRTT2 gearbox which was close ratio. But the very high first gear made the bike difficult to get moving from a standing start. The problem lies only in moving the first ten feet from a set of traffic lights. You need the low first gear - everything else is easy.