Poorly Running Engine after Plug Reinserted.

[kmisterk]

So, I recently discovered that my r100, at one point or another, had the Pulse Air and Fuel Solenoid Deletion process done, but for some time (unknown if it was before or after I got the bike, as it's something I *just now* noticed), the right-side cylinder head has had its "plug" for that evap deletion missing.

After having found a suitable plug and crush-ring replacement for the hole, and having sealed it, it idles *extremely* poorly, and I wonder if, perhaps, it's been running like this (that is, without one of the pulse air injection holes plugged) for a while, and was tuned this way, how do I go about making it idle better? And, for that matter, run better at large. It loses power, now, after 3500 rpm under load. The bike is overall *much* quieter, now, unironically enough, considering the entirety of the muffler is now being utilized, but I digress.

For it to run optimally with both pulse air evap holes (or, whatever they're called, just below the exhaust ports on the front of the cylinder head) plugged, what do I need to do? What to adjust?

**Additionally**...

After reading through snowbum's PulseAir article, it doesn't seem that the hole being plugged again should have made all that much of a difference in how the carbs perform. But somehow...it seems like it has. Is this plausible at all or am I missing something here? I feel that more testing is needed, but any insights? I won't likely be able to get back to the bike until after this work week.

[gspd]

For it to run optimally with both pulse air evap holes (or, whatever they're called, just below the exhaust ports on the front of the cylinder head) plugged, what do I need to do? What to adjust?
It's called a EGR port (Exhaust Gas Recirculation). A missing plug will just cause more noise and have very little effect on performance.

How do I go about making it idle better? And, for that matter, run better at large. It loses power, now, after 3500 rpm under load.
Sounds like a textbook case of a holed carb diaphragm.

[Rob Frankham]

The first move is to carry out a full carb tune with the plug in place... or rather that's the second move, the first move is, as GSPD suggests, to check things like carb diaphragms and other obvious thing s that might affect running. The unblocked port may not affect achievable performance but it will upset carburation on the affected side and that means it will also affect carb balance.Once you've done a full tune, if the issue hasn't gone away, then is the time to start looking at other causes.

Rob

[daz]

Both throttle cables are seated properly?

[kmisterk]

Thanks for the responses, guys! I haven't ignored, but I do not have immediate access to the bike right now (it's at my parents).

I will check throttle cables, and then if it's good, I am thinking it's about time for a carb tuning/syncing. Rebuild, possibly.

[kmisterk]

How do I go about making it idle better? And, for that matter, run better at large. It loses power, now, after 3500 rpm under load.
Sounds like a textbook case of a holed carb diaphragm.

I don't believe this was the case, now. I did a lot of maintenance on the bike last week and it has been running like a *dream* ever since then.

Both throttle cables are seated properly?

Seated? Yes. But they were loose and improperly routed through the rubber tube clamp. Fixed that and adjusted them, among other tuning processes, and it's running amazing now!