Breezy, I don't care if you built the space shuttle, you obviously know nothing about these bikes. Old triumphs and volkswagens are nothing like one of these bikes, other than the fact they have wheels attached. You are going the right way to turn into a typical PO of one of these bikes, someone with no clue on what they are doing, then do a half arsed job of it then blame the bike and sell it on to someone else or worse just park it outside and forget about it. WE NEED SOLID DATA to go by, What is your engine speed at 65mph, use a digital tacho like one on a dwell meter, failing that WHAT DOES YOUR TACHO READ AT 65? IS YOUR SPEEDO ACCURATE? Get someone to ride alongside you and see what their speedo says, or use a GPS. If you can't start providing some solid data to work off of we can't help you and to put it honestly I have better things to do with my time than try and help someone who is either too arrogant or stupid to listen to the people who are on this board . Good luck destroying your bike.
Well if Honda SOHC's are rocket science, as you seem to feel, then maybe you should care if I built the space shuttle. But they are not. They are a Carnot heat engine, a number that has been on the planet since the late 1700's. I tend to be logical and not follow the dictates of churchmen unless they are using logic as well. Let's do some logic:
1. I'm on the highway with a speed limit of 55mph, keeping up with traffic. I have maybe an eighth inch of throttle left, the engine is screaming, I'm in 5th gear searching for a needed 6th gear. 5mph plus or minus is not going to effect the gross results. With that data set, my tach reading is simply not necessary. A couple of comments mentioned the variability in Honda tachs, so why make that a hinge point in this analysis?
2. My buddy who I got the bike from said it was riding fine, he could do a ton, barely- it's an old bike. He puts the bike away and concentrates on finishing up the body restoration on his 900RR. I get the bike, do some repairs and put on a new rear tire. That is the only thing I did to the drive train. I gave you the specs on the tire and asked anyone to stretch a tape measure around their 18" rear tire and give me a number to compare with mine. This seems to be an approach that will verify or eliminate a variation in tire dimension as a factor.
3. The clutch was not slipping when my buddy put the bike up, the clutch is not slipping now. I can bring the front wheel off the ground.
4. It is not necessary to change all secondary drive train components in all cases. The rear sprocket is like new, the chain is like new, maybe 1/8" total end play when compressed then stretched lengthwise, the front sprocket is toast. I'm not made of money, I think I'll just get a new front sprocket.
5. I put the tooth count on my sprockets up here. They are accurate counts. A picture is not necessary.
6. If necessary, the front sprocket will be sized according to the percentage difference computed according to the difference in my top speed vs. the stock top speed, with a little subtracted to compensate for the age of the bike. If the sprocket I end up with is too big for the housing, I'll remove metal from the housing, far cheaper than getting an 18" rear tire with a fatter profile and setting the tire I bought on fire at the next Occupy (city of your choice) protest.