After the rebuild

[dave Esch]

I got a battery in the bike today and started it up. Unfortunately, as always, it misses when cold and smokes pretty good at start up. I figured the new valve seals would prevent the leak down while the motor was off, and I figured honing the cylinder walls and installing new piston rings would solve this issue. Much to my dismay it has not. Not sure why it misfires. The only thing that came to mind was bad gas. It is almost two years old. Tomorrow I am draining and refilling the tank and adding a bottle of seafoam. I hear pretty good things about it. The seafoam may even loosen up my carbs. Even with new throttle cables it doesn't "snap" back when you release. Rather I have to actually push the throttle back to go to idle. I dunno guys. After startup she's a real ball breaker, lots of power and great throttle response. Since she IS 37 years old I guess I should be pleased but....

[pat english]

sorry to hear about the miss fire issue..sucks to do all that work and not run perfect..maybe youre timing is off?...you should take the throttle assembly apart and see if the grip is binding...it sounds dumb,but it happend to me the other day..i took the throttle assembly off my 750 and put it on the 250 bars..well theyre both 7/8s bars but the grip was binding on the 250 bars and not the 750 bars...very strange.

[Re-run]

Well the binding could be a routing issue, the throttle sleeve could be binding on the bars, did you lube the cables if they are not honda cables, do the carbs snap shut without the cables attached?
If the carbs snap shut, you know it is the cables somehow.

2 year old gas is bad gas. Especially if it had ethanol in it.

As for smoking, it can take a bit for rings to seat sometimes. After a few hundred miles, a leak down test should be done and should hopefully show good readings.

Another issue might be ignition or carbs. Old gas, in the carbs can cause misfires if things are crudded up.
Maybe after the bike is warmed up and off choke, pull the plugs and see if things are rich.

What color is the smoke?

[dave Esch]

The smoke is dark gray, pretty definitely oil. No the carbs dont snap back without the cables, cables are brand new. I'm not sure if this is the issue, but rode it again with same problem. Then started missing really bad. I switched to reserve and the missing stopped damn near instantly. About to put the seafoam in it now and ride it again.

[sgtslag]

SeaFoam will dissolve varnish pretty handily, but only if it is not plugging any jets.  Did you overhaul/clean the carbs yet?  Try the SeaFoam, first, as it is the easiest.  If that doesn't help, then pull the carbs off.  I've had a few friends use it in the gas tank, with great success.  It is a minor miracle, sometimes, other times, it does nothing noticable.  It is inexpensive, and easy to use, though.

I would recommend running it through the gas tank once every 45 days, or so, just as a precaution, to keep ahead of the varnish deposits in the fuel system.  Ethanol gas goes bad, according to some articles posted on the Internet, after just a couple of weeks time.  It will only reduce your mileage a little bit, but if it scours the fuel system, avoiding more severe problems, it is worth your time, and money.

I would recommend SeaFoam in the crankcase, as well.  Add according to the bottle's directions.  Run it on the center stand for five minutes (if cold), shifting through all gears, letting the rear tire spin with the engine idling only.  After five minutes, the oil will be around 180 F.  Check its color, before you start, and after:  it most likely will turn jet black after five minutes of running with SeaFoam in the crankcase.  This will be carbon deposits, varnish, and other sludge the SeaFoam will have dissolved within the engine, and the transmission.  Much of it will be caught by the oil filter -- change both the filter, and the oil, but do NOT add more SeaFoam (isn't necessary, one treatment will last many, many thousands of miles, with regular oil/filter changes).  YMMV.  Cheers!

[dave Esch]

Today on my way home for work I peeled my helmet off... accelerating. I don't know what happened, maybe the sea foam is working, but the second half of the ride home was a real ball buster. No hesitation. No sputtering. I checked and double checked the timing before I put it together because I was uncomfortable with it. The manual states to line the contact breaker plate line up using the line over the letter "T". In the manual the line is to the right of the T. On my bike, the line is to the left of the T. So I wasn't sure which line to use and this caused me to doubt my timing set up. Now I know by experience with CARS, being off even just one tooth will allow the car to run but very poorly since complete combustion is impossible. However, the bike was accelerating fine and idling fine as long as I didn't give it a lot of throttle all at once. This afternoon I was really putting the hammer down and it seemed great. The only running issue I had was the backfiring at idle. I have a four into one drag pipe with no baffles. The popping I am used to on deceleration, but it never did it at idle. I am idling a little high because I have to adjust my new cables still. But it still seemed odd to me. I did a lot of work to this and want to get it running as best I can, so there are still some this and that's to see to.

[dave Esch]

I think I have all my bugs worked out now. I found that my carb return spring was stretched beyond usability. I went to Lowes and bought a tractor return spring kit and found one almost the exact length. No more sticky throttle. She snaps right back now. As far as the popping at idle, as well as the high idle, just by looking at the carbs I could see that #4 was sticking up a little higher than the others. I pushed it down maybe 1/64 " and the idle dropped right down. So I adjusted the one carb. No more back firing at idle either. And the sea foam has evidently made it's value known. As soon as that motor gets warm the hesitation under full throttle goes away. I went out in full safety gear last night on a self-destruct mission. I wanted my confidence in my Honda back. So I rode it harder than I ever have or ever will, spinning that huge drag sprocket up to 110 mph with ease. I also left the needle on redline for a while as well. If it was going to fail, it would have done so yesterday, close to home, when I was prepared for it. She's a runner. Thanks everyone for all your input with this project. I couldn''t have done it without you guys.