I ask again, whats the trick to tune 81 carbs??????

[andy]

The 81/82 carbs are really lean on the bottom and slow to warm-up; is there a trick to enrichen the mixture during carb synching short of tilting the motor and re-jetting?

Only reason I ask again, 35 views, no reply.

[Tom Whaley]

Andy,

I don't know of a way to richen the mixture as you ask. I believe that is the way Honda sent them out of the factory. It has to do with emissions.

[xneric]

Andy, syncing carbs is to get all butterflys to open at the same time so each cylinder is doing it's fair share. There is no way this affects the mixture, but a good sync will make the engine run more smoothly, and sharpen throttle response more than you could imagine. It might not eliminate your problems completely, but it could help a lot. Eric

[andy]

Thanx 4 your response! But I thought there was some way to outsmart those factory set idle mixture screws on the bottom of the carbs, something about bypassing the tabs or some other ingenuity to make it a bit richer. Some other models had plugs hiding idle air screws that were ez to remove.

[xneric]

Yes, Andy, you can melt those plastic caps off the metal screw. I think some people use a soldering iron to heat the screw to melt the plastic cap. This allows you to adjust the screw to any position. Getting them right might help your problem a little too. Also, make sure your accelerator pump is working. Eric

[andy]

Aha! So those black caps should come off. Anybody have experiance tweaking this procedure?

[Dave Ditner]

I think you'll find that the limiter caps are not plastic, but zinc die cast pieces. Not to worry though, they're held on with super glue and a soldering gun held on to the bottom will heat them enough to melt the glue so the gaps can be removed. Ain't gonna be easy though with the carbs on the bike. Open the screws to2 turns to start. You'll probably end up at about 2 1/2. If you really get frustrated and take the carbs off to remove the caps shim the needles while you've got them out. Mine are up .028" Mains should be pretty close with everything else stock, (exhaust and air filter) Emission testing ignores wfo conditions, looking only at part throttle.

[Ric]

Yeah....be careful pulling those caps off, you'll break one of those pilot needles their attached too.

[cbxlarry]

Previous comments are correct that the adjuster screw caps are zinc. Got to be VERY careful not to break the screw stems. The stems intentionally are very thin to do just that: break if someone tries to force them. Obviously, removing the carbs and heating the caps on the stems to break the glue joint works. An alternative that I just did involved some tedious knuckle busting and some time; but, it worked and didn't require removing carbs.



It was as simple as wiggling a hacksaw blade back under the carb bodies and cutting away enough of the boss on the carb bodies so that the wing on the screw caps can clear for rotation. The zinc cuts easily. Turn the screws a 1/4 turn 'in' to get clearance for the hacksaw blade. Note: on the left side you will have to pull the alternator to have enough clearance to work on the inner carb. Clearance was OK on the right side. Be careful when turning the screws. They might stick initially because they've been sitting for years. Use the screw driver slots if at all possible by whatever means you can find or buy.



After you have the lugs cut, turn the screws in to full closed. You can tell by feel. When they quite turning, they're closed. I opened mine 2 1/2 turns. Improved starting, improved warm-up greatly, and improved off-idle response significantly. Good luck.