Is the speedometer on a C10 even close?  Mine shows about 71 MPH at 4,000 Rpm but it seems like I am going slower than that. It is more open to the wind than my wing which usually gives the feeling of more speed.
Took it out for the first real ride yesterday morning and had on my riding boots and mesh overpants over blue jeans and didn't notice the heat but today coming home from work in 100+ heat with my low top work boots and uniform pants on my legs about roasted. Had to hang them down off the pegs occasionally to get some relief.

Well...
I run with a GPS on my dash, and my 01 speedo is dead on. And my legs get hot because there is a 998cc engine just inches away. There are heat shiekds available from one of our fellow Connie owners on here, as far as the speedo, how old is your bike, how many miles on your cacle?
Oh yhea, 4000rpm = 71 mph on mine also.
Hope this helps.
Ride safe all.
Greg

Running a Wing sized front tire, my speedometer and GPS are identical, or as nearly as I can tell, anyway.  With the stock size tire, the speedometer will read a bit higher than actual speed.

Thanks, I guess it's close enough.
Note to self, wear riding boots and pants.

On my 87 with OEM tires the speedo reads high by approx 4mph at 60mph indicated.

110/80-18 front and 150/80-16 rear - at 70mph indicated, GPS shows 68mph. In fact all the way from 30-90mph, the speedo seems to show 2mph more than the GPS.

With stock tires, my Speedo/odo was about 3-4% off, so I saw between 103-104 miles for every 100 traveled.

With wing size tires, my speedo/odo is now off about 1%, or 101 miles for every 100 traveled.

Most of the posts I've seen in the past seem to concur that in stock trim, the Connie speedo generally reads faster than your actual speed.  But of course, YMMV...

Stock size front tire and my '05 speedo read 1mph faster than what I'm going according to GPS.  Close enough for me!

Well...
 And my legs get hot because there is a 998cc engine just inches away.
Hope this helps.
Ride safe all.
Greg

Just had to make a comment on that.
On my grown up bike I have 916cc just inches from EACH leg and they don't get hot. And on my other little bike I have 542.5cc just inches from EACH leg, it is a little warm but not like the connie. 

Yeah, you got a radiator in front with a fairing that funnels hot air past your legs. anything much over 85 or so, I tend to ride the air cooled, unfaired KZ. There are different ways to cope, like Greg said, shields, some use the air wings, me, I just spread my legs a bit.

My speedo shows about 5-6 mph high across the board compared to my gps at highway speeds.

I can help with the hot legs issue to some degree (that's a pun (.  I make the heat shields, and if you are interested in them, send me an email to bp snow at hot mail dot com

Im with 2fast. 
My speedo shows about 4-5mph above whats displayed, but on stock size tires.

On the heat issue, I have his heat shields but have yet to install them.
Been trying to figure out where most of the hot air comes from before I do so I can make a very crude before and after assessment.  It would seem so far, most comes out the upper area around the tank/fairing opening (by the petcock for instance).
I also think part of the heat issue is the fact that the pipes are open to most areas inside the fairings.  There is a LOT of heat radiated off of them into other parts and the air coming thru the radiator passes over them as well before it exits, usually near your legs.
I have had a set of headers ceramic coated, but have yet to install those as well.  Been a busy Summer so far.  They are coated inside and out, and should keep the heat in better, and have almost zero radiated heat (things around them wont get hot just because they are close), so it would seem, in theory anyway, they would reduce the heat quite a bit.;

Im hoping there is some relief from that once I get Brians heat shields in place and the header mounted. 
I dont expect a miracle, just something a bit more tolerable.

I hear all the time the excuse that its 1000cc and it makes heat and its got to go somewhere...but Ive had bigger bikes that put off less heat thru the fairings, so its more of a heat management issue than the size of the engine.  And the argument that its a larger fairing only holds for the upper part.  My RF900 was every bit as big down low as the C10 (even had the same type of plastic between the fairing and the tank/engine!), but never roasted my legs.
ZX11 didnt either, and THATS a big, powerful engine. 

I used to go for a ride in the Summer to cool off, but a ride on the Connie has the opposite effect. 

Oh. THAT'S what you meant by "hot legs".
Was hoping for some interesting pics. 

I have Brian's heat shields installed on my '99.  They make a world of difference!  I still feel some heat on the inside of my feet, but most of that could be hot air being funnelled in off the road through the side scoops.  Oh and there's still an engine down there.

I'm working on some boot mounted weenie roasters.  Take a ride....have a snack.  I'll let you know how they work out. 

I use Brian's heat shields, the stock side air scoops, some China Crap(tm) Baker Wing wannabees, and Gen-mar foot peg relocators. First off, the 2fast shields really work. The Gen-mar foot peg relocators, aside from lowering the foot pegs, also put them farther away from the bike, guessing 3/4 to an inch. This is enough to get my feet away from the direct blast coming out of the engine compartment. Also helping in this, is that the stock air scoops tend to form an air curtain of outside air, the Gen-mars keep your feet on the outside of the heat stream. Caveat, you have to get used to being a bit pigeon toed to work the controls, or maybe bend the shifter and brake pedal out.

This system works well for me, but it doesn't get as hot here as the rest of the country. who'da thunk that you should go to FLA in July to cool off.