Honda 185s... So close, yet so far away...

[Jonny Robertz]

Okay, so I have posted the many issues I have had on this Honda 185s project. I think I have worked out most of the kinks and it is running again. Sort of. Now it runs okay with the choke fully on. By "okay", I mean it starts and runs but the idle is sort of all over the place. At first it is moderately high, then after about 2-3 seconds it slows down to normal. Then it is back and forth between normal idle and almost shutting off. This is all with the choke on. If I adjust the choke to half or off the trike dies immediately. It seems like I am an adjustment away from this thing running normally. Now, I am fairly new to diagnosing problems with these because, let's face it, this a Honda and generally only requires basic maintenance and the occasional carb cleaning. However, my guess is that I am getting too much air...? If the choke is on I am not allowing let air in, and with it off I am opening the carb to the air box, right? I know there is a pilot air screw up on the bottom of the carb and I have heard anywhere from 1/4 turn open, to 1.5 turns open, to the manual recommendation of 2 full turns open. Also, the screw on the side of the carb that actually touches and adjusts the slide level, any idea what the setting is on this, or is it just a tuning thing that I need to play with while it's running? This is also the pain in the ass idle adjustment that is a small nut on top of the cap on the carb with the needle and throttle cable running through it. This is really tough to adjust while it is running but I really don't know where it should be. When I had it running good before it was about 3/4 of the way up. It may be a combination of adjustments but any input would be helpful. Maybe I have an air leak? If so, where do I start looking? I always feel like I am on the right track with thing but it's like 1 step forward and 2 steps back for some reason. I bought this and an 85 250sx in the same deal and I had the 250 up and riding perfect in like 2 weeks and this little 185 is driving me nuts! Help!

[webbch]

- The nut on top of the carb isn't for adjusting the idle. It's for adjusting the free play in the thumb throttle.
- The screw on the side that adjusts the slide level is your idle adjusting screw. To adjust the idle, I use a timing light with an RPM readout. I believe spec is 1400 RPM +/- 100
- To check for air leaks, you spray carb cleaner on the intake port connections and listen for surging

Now move on to the carb. Nothing affects your fuel mixture in all ranges more than the float level....so remove your carb and set the float level to what's specified in the manual. Too high and you run rich. Too low, and you run lean. This should get you 90% of the way there. The reason some may have so much variation on their pilot screw settings IMO is quite likely because the float level isn't quite right, but you can compensate the idle to a degree, but may create mid or high range issues.

I went through what may be similar trials on my 200s recently. Idle was all over the place. In my case, when I would rev the engine, it was VERY slow to return to idle. The float level was WAY high, creating an excessively rich mixture.

I believe the stock slow jet on the 185s is a #35. A #38 or #40 may help a little as well.
here (http://www.3wheelerworld.com/showthread.php/141103-basic-carburetor-tuning?highlight=carb+tuning) is a very informative posting on carb tuning that I found helpful. I think the article doesn't stress enough how important the float level is, but is otherwise a fantastic help.