Another idle/throttle issue

[JGard]

I was hesitant to post a thread about this because I've seen SO many like it and I've spent the past two weeks reading through them all. However, I'm fairly stuck at this point, so I figured what the heck.

I bought an 02 R11S about three weeks ago and from the test ride on, I knew it had a "low idle", according to the previous owner. Since I hadn't taken it for really long rides for the test, I didn't think much of it, since the choke lever high idle was fine and it seemed totally fine at speed.

After two days of commuting on the bike I realized there was a real problem. The right-side cylinder seems to sputter a bit and at "low" idle it would stall after a few seconds. Warm startup also wasn't great. Since the owner told me the bike had a PCIII installed (from the owner before him), I assumed that was the issue. Long story short, there isn't one installed.

So now I've begun the full 12k service (even though it had one only 6k miles ago...bike has 20k miles now total). I did the fuel filter, valve adjustment, put in a Bosch o2 sensor, new wires, and an oil change so far. (something that's frightening is that the fuel pump is much louder now after that filter replacement, but another issue for another day!)

I just went out to try and sync the TBs and I'm having absolutely no luck. I backed the BBS' out to 1.5 turns each, loosened each throttle cable, and tried adjusting the left throttle stop-screw, first, because both were all the way backed out when I first looked at the bike. I just wanted the idle to be around 1,000-1,100RPM. Now that I have the left set so that it is around 1,000, I go to set the right-side.

This is where it gets tricky and annoying. No matter how much I turn in the stop-screw on the right TB, nor no matter how much I back out the BBS, the left-side cylinder is always pulling more air than the right-side. On the Twinmax, if I have sensitivity turned all the way up, it's around the 3 mark, if I have sens turned up about 3/4, it's more around 1 mark left.

That said, the bike is idling pretty well right now (in so far as the sputtering is gone and it stays at a constant speed without stalling). However, it's still very vibratey (not a word, but the best I could think of) and whenever I twist the throttle, it pops and bogs before the engine spins up.

I have not done the zero=zero TPS adjustment yet, so I figure that is next. But I'm not convinced that'll solve the inability to balance the TBs. Any thoughts, advice, words of encouragement, insults? I appreciate it. Sorry for the long post, I'm beginning to think this was a bad purchase.

[boxa]

Have you done a compression or leak down test?

Thanx
Dave

[JGard]

I haven't, yet, but I fear that's the next test. I can't get the spark plugs out right now because the toolkit that came with the bike just happens to be missing that tool, and of the 5 sockets I have that should fit a spark plug, none will... But yeah, I'm beginning to think there's a potential compression issue in the right cylinder which would really, really, ruin my day.

[ckcarr]

Maybe the previous owner was a slacker and didn't tighten a plug or plugs all the way correctly. Perhaps he had the same issue you seem to have (no proper tools). Might be a simple fix.

I have to ask, now that I've re-read this thread, have you ever removed or changed the plugs? There was no mention whatsoever in the first post. Yet you did all that other work?

A serious mechanical issue is highly unlikely,like blown head gaskets or stuff like that. I believe you are relying on information that may or may not be true as far as the 6,000 mile service being performed. Who did it?

Change the plugs, add some Chevron Techron (ha! ha! stole from below) and ride it for a tankful.

[R111S]

A 10 year old fuel injected motorcycle with only 20k miles would be ripe for clogged/varnished/dirty fuel injectors. Maybe that's why the fuel pump is loud?

I'd run two or three tanks (400-500 miles) with Techron Fuel System Cleaner before doing anything else.

I use Techron two maybe three times a year in all my fuel injected engines ('07 VW Passat w/111K Miles, '97 BMW 318ti w/138K Miles, and '99 R1100S w/74K Miles) and they all run well.

[JGard]

Yeah, that's the other thing I'm hoping for, is a clogged injector. Much better than having to rebuild the motor. I have a full tank of Chevron in there now and honestly I'm a little afraid to ride the thing. It can't hurt to send the injectors out to get flow tested and cleaned, I'm thinking.

I'm hoping I can find the spark plug tool soon, then I'll go buy a compression tester and see how it goes. It's just to the point where I'm nervous and expecting the worst.

[jaytee]

Yeah, spark plugs first for sure. Until those have been replaced I'm not sure I would be worried about anything. Also, do you know if the bike has a temp spoofer on it? Could be over-richening perhaps? Another thought is a bad coil.

[rckendall]

From the statement that the right throttle body is not responding to adjustments to the BBS, it seems like the passage is blocked. Maybe try removing the BBS and blowing through it. You should be able to adjust it.

Or, you may need to remove both throttle bodies and clean them up on the bench, where you can really check them out thoroughly.

Richard

[Drews323i]

I had these same symptoms with my bike when I got it. Heck it died 3 times on me when I was riding home. Horrible idle and stumbling on acceleration. I installed new plugs, TB sync, and Techron for 2 tank fuels. Runs perfect now. Definitely need to change those plugs before going any further so you know what your working with.

[R1100S2000]

Certainly not a bad purchase. with the help from this forum you will get through this and you will certainly enjoy the uniqueness of the this wonderful bike.

This prob not the issue but what the heck, maybe the throttle cable isn't sitting correctly on the TB it is very easy to knock it off and not notice.

[JGard]

Thanks all. I'm hoping beemerboneyard comes through and has the stock spark plug tool so I can replace that. but yeah, the throttle cables all look and work ok. I replaced the wires for the same reason I want to replace the plugs, figuring they may be bad.

I have tried removing and cleaning the bbs', too, and the right-side was, in fact, quite dirty compared to the left.

finally, if it's a bad coil, i'm ok with that, too. easy fix. From what I've been reading, at this bike's age, it's entirely possible it's gone bad.

Thanks again. I don't have a ton of time to work on the bike this morning, but I'm tempted to pull and clean the fuel injectors. If that fails, I'll wait for the spark plug socket remedy, and if the plugs don't fix it, then I'll think about removing and cleaning the throttle bodies entirely.

[PFFOG]

Originally Posted by jaytee

Yeah, spark plugs first for sure. Until those have been replaced I'm not sure I would be worried about anything. Also, do you know if the bike has a temp spoofer on it? Could be over-richening perhaps? Another thought is a bad coil.

Agree 1000%, in my 40+ years of playing with internal combustion engines, and being service manager in dealerships, I have seen many a professional mechanic pull out their hair, trying to fix an issue that was caused by the simple bad spark plug. AND the fact that they were fairly new, and looked fine, CHANGE THEM, If the identical symptom exists before and after, then start looking. I have seen as many bad new plugs as old.

[JGard]

low and behold, I fixed it... mostly fixed my being a damned idiot

the right-side throttle cable/sync cable, which I thought was pretty loose, apparently wasn't nearly loose enough. That, and I guess the way the twinmax was reading was the opposite of what I was expecting.

So I did pull the injectors and remove the bbs's and spray a liberal amount of tb cleaner in both openings on both sides. Then once I put it all back together and completely loosened the sync cable, the twinmax read in the opposite direction, so I knew the cylinder wasn't bad.

Yeah, so at this point, it's idling smoothly at 1,000RPM, engine spins up smoothly, and decelerates smoothly. Once again, I guess I hit the panic button too soon

but I still plan on replacing those stupid sparkplugs soon! haha

[R111S]

Great news and good work!

[ckcarr]

More evidence that doing the simple things first usually work.
Occam's Razor in a way, although not exactly.