Hesitation on throttle, and then worse

[dylanewilliams]

I checked the hall sensor and it seems to work fine. I followed the instructions on the link I asked about earlier, and at both cold and hot temps inserting a knife in the sensor shut off the led, although I think I might have got it too hot, as the plastic on one of the sensors started to melt.

I am now going back to focusing on fuel, checking and cleaning the injectors, and checking for leaks in the intake manifold.

I also have half a mind on the coil, my manual says the secondary resistance should be 1300, the advrider guide says it should be 13K and I have 7.25 Ohms.

One of the early services I did and didn't mention was cleaning and reoiling my K&N air filter. In a lot of other threads a new filter keeps coming up, so should I discard the K&N and get a new air filter?

EDIT:

I put the hall sensor back in, put everything back together, and tried starting the bike. it wouldn't run unless I kept the throttle fairly open, and died as soon as I let go. I pulled one of the fuel injectors, and the tip looked clean, but I'm going to Kragen and will buy a fuel injector cleaner and soak both overnight. I'll also buy something to test the pressure of the fuel pump.

A separate but possibly related issue, the tube that connects to the tank filler nozzle, that's for letting air in to not create a vacuum in the tank, leaks fule. It's done it for a while, but I didn't pay it any mind. I broke my rear shock on a pothole in costa rica and the charcoal canister was destroyed, so I figured the leaking gas was the condenate from the tank condensing in the line and then dripping out instead of evaporating, as it would have in the emissions canister. Today, however, after I just tried cranking the motor, about five seconds after I gave up, a fair amount(maybe a few ounces) of gas shot out of the tube. I have no idea what that's about



BTW, I would love to get a new bike. If this had happened six months ago I would have. Unfortunately, I just transitioned from working back to school, so that's not really feasible right now. If it comes down to it though, I probably will get a KLR650. I could probably get one for the price of this bike, and I saw a lot of guys in Central America with them. They seem like a good alternative to the GS for people on a student's budget.

[def]

Originally Posted by jalapenopete

I had a '98 GS that I rode the crap out of. The last couple of years it was fix this, fix that, what now? The last big trip was from my home in GA out to Yellowstone and back last summer. I had a $2K+ bill to get it ready. The bike was good throughout. But, I got back and said "y'know, it's time for a new bike". Bought a lightly used 2010 GS and I'm happy as a clam. The new bikes are stratospherically (not sure that's a word) better. Of course you'll have these guys telling you that an old GS can be fixed on the side of the road by whittling a wrench out of piece of wood and replacing the starter from a '65 VW parked conveniently nearby, shit like that, but I'm not a mechanic.
Maybe you should just get a newer bike. I mean carburetors.... hello 21st century! A newer bike under warranty means BMW will pick you and the bike up, fix it, put you in a hotel, and the hassles are done.
IMHO.

The oilhead boxer has been fuel injected for years without much drama. Carburetors have all but disappeared on everything but weed eaters. Maybe the OP will eventually opt for a new bike but, I'll bet he'll want to get to the bottom of his driveability issues on his current bike until that time. Stratospherically better? I'm not so sure. Stratospherically different? Yes. Stratospherically expensive? Absolutely! As for BMW picking you up and wining and dining you if their motorcycle hiccups? Not on this planet.

[def]

Originally Posted by dylanewilliams

I checked the hall sensor and it seems to work fine. I followed the instructions on the link I asked about earlier, and at both cold and hot temps inserting a knife in the sensor shut off the led, although I think I might have got it too hot, as the plastic on one of the sensors started to melt.

I am now going back to focusing on fuel, checking and cleaning the injectors, and checking for leaks in the intake manifold.

I also have half a mind on the coil, my manual says the secondary resistance should be 1300, the advrider guide says it should be 13K and I have 7.25 Ohms.

One of the early services I did and didn't mention was cleaning and reoiling my K&N air filter. In a lot of other threads a new filter keeps coming up, so should I discard the K&N and get a new air filter?

Here's my BMW REPROM Coil specs for my 2001 GS. Yours should be similar. Primary= ~0.5 Ohms Secondary= ~7.5K Ohms (cold) Remember, the ignition is a wasted spark design. K&N filter? Remove it and run the engine without the filter to determine if you're starving the engine for air. This may be the reason for the black plugs. Also, I read a recent post where the rider discovered air intake tubes that were blocked. Check for unobstructed air flow from the air box to the throttle bodies.

[Mrmerlin]

make sure to swap out the O2 sensor just checking wires isnt enough

[Jim Moore]

The 13K spec is wrong. it's 7K. You're good there.

[Jim Moore]

Originally Posted by dylanewilliams

A separate but possibly related issue, the tube that connects to the tank filler nozzle, that's for letting air in to not create a vacuum in the tank, leaks fule. It's done it for a while, but I didn't pay it any mind. I broke my rear shock on a pothole in costa rica and the charcoal canister was destroyed, so I figured the leaking gas was the condenate from the tank condensing in the line and then dripping out instead of evaporating, as it would have in the emissions canister. Today, however, after I just tried cranking the motor, about five seconds after I gave up, a fair amount(maybe a few ounces) of gas shot out of the tube. I have no idea what that's about

There is something wrong there. You have a problem inside your tank.

[jalapenopete]

Originally Posted by def

The oilhead boxer has been fuel injected for years without much drama. Carburetors have all but disappeared on everything but weed eaters. Maybe the OP will eventually opt for a new bike but, I'll bet he'll want to get to the bottom of his driveability issues on his current bike until that time. Stratospherically better? I'm not so sure. Stratospherically different? Yes. Stratospherically expensive? Absolutely! As for BMW picking you up and wining and dining you if their motorcycle hiccups? Not on this planet.

The BMW warranty definitely covers roadside pickup, and overnight accommodations when not within a day's travel to your home. It's just an insurance policy, and works just like the Allstate policy I have on my (out-of-warranty) R1200S.
No wining/dining stated or implied. The new bikes are also lighter, much more powerful, more nimble, and get better gas mileage. You'd have to come off of a 7,000 mile trip on a '98 GS and hop on a newer (mine's a used 2010) a week later. A much better bike.

[dylanewilliams]

After checking all the things I listed above, with everything seeming OK, I started the bike and it idled! although, not very well. I tried to sync the TBs, but wen I came into range on the R TB, it started knocking horrendously. I think that the problem turns out to be just that the throttle body is not functioning properly, and the sync got so bad the bike wouldn't run. I am trying to order a rebuild kit from Dan Cata now. I will post if that solves my woes.

[vintagerider]

"After one left hand turn the hesitation was enormous, the motor almost died"

Typical ignition switch harness failure symptom. Pull the tank, use the secret method which we don't publish on the forum to release the switch harness from the key lock. Check the switch solder contacts. Open the outer sheath and look for bad internal conductors. They zip tied the ign switch harness too tightly to the frame.

1996 model year- most had single throttle cable.

Can also unplug the side stand switch located under the air box LS and do a temporary by pass to eliminate high resistance in the switch. Also check the wire leading in to the switch block under the tank for signs of over-heating (green red stripe?).

Yes the early 1100 gs TB's and single cable suck and benefit from svs but I bet that is not the problem you described.

edit: so much here, remote diag is kinda silly. But did you do a compression test?

edit: Bet you blew off the out-flow limiting device located on the inside of filler neck. Never introduce compressed air in to the tank dual purpose vent/overflow line or the filler neck drain.

edit: When you busted the kanister did you: 1) block off the vacuum ports on the TB's? 2) insure that the dual purpose tank vent/fuel over flow vents freely to atmosphere? (seems like it). This is the stock set up for non-U.S. 1100. Ounces of fuel should not exit the tank unless over-filled. The kanister does not function as you described.

You may have several issues but best place to start is with full fuel prep and delivery system inspection and maintenance. It's a fairly simple system. It takes a little patience to sit down and study the system but once you do it will all click in place. The regulator doesn't do anything until the sys reaches op press then opens like a relief vlv to return un-used fuel to the tank. Def has a point on checking air inlet as critters like to build nest in there. Front large tank port should feed to the fuel dist inlet. Rear is fuel return.

If the pump is original then read crackhead's alt pump thread using my recommended pump sub. You can skip buying a fuel pressure test kit unless you are doing performance :) tuning.

Cool that you adv this in Central America.

[dylanewilliams]

Originally Posted by vintagerider

"After one left hand turn the hesitation was enormous, the motor almost died"

Typical ignition switch harness failure symptom. Pull the tank, use the secret method which we don't publish on the forum to release the switch harness from the key lock. Check the switch solder contacts. Open the outer sheath and look for bad internal conductors. They zip tied the ign switch harness too tightly to the frame.

After someone tried to steal the bike (I think), the steering column lock pin that engages into the frame broke, and actually stuck into the frame as I pulled out of a parking spot, causing me and the bike to go flying. In the process of removing the ignition switch, I drilled and easy outed the one way screws, and the drill chuck tore some insulation off the wires there, which I taped back up. Could that be causing the problem?

1996 model year- most had single throttle cable.

Can also unplug the side stand switch located under the air box LS and do a temporary by pass to eliminate high resistance in the switch. Also check the wire leading in to the switch block under the tank for signs of over-heating (green red stripe?).

Yes the early 1100 gs TB's and single cable suck and benefit from svs but I bet that is not the problem you described.

edit: so much here, remote diag is kinda silly. But did you do a compression test?

No, should I

edit: Bet you blew off the out-flow limiting device located on the inside of filler neck. Never introduce compressed air in to the tank dual purpose vent/overflow line or the filler neck drain.

How can I fix it? do I need to replace the whole filler neck assembly?

edit: When you busted the kanister did you: 1) block off the vacuum ports on the TB's? 2) insure that the dual purpose tank vent/fuel over flow vents freely to atmosphere? (seems like it). This is the stock set up for non-U.S. 1100. Ounces of fuel should not exit the tank unless over-filled. The kanister does not function as you described.

They are not blocked, they lead back to near the rear footpeg and are open to air there

You may have several issues but best place to start is with full fuel prep and delivery system inspection and maintenance. It's a fairly simple system. It takes a little patience to sit down and study the system but once you do it will all click in place. The regulator doesn't do anything until the sys reaches op press then opens like a relief vlv to return un-used fuel to the tank. Def has a point on checking air inlet as critters like to build nest in there. Front large tank port should feed to the fuel dist inlet. Rear is fuel return.

If the pump is original then read crackhead's alt pump thread using my recommended pump sub. You can skip buying a fuel pressure test kit unless you are doing performance :) tuning.

Cool that you adv this in Central America.

Thanks!

[vintagerider]

1. The switch can be separated from the lock w/o messing with the one way screws. Unplug the end under the tank Now you have the swtch w/harness on the bench that you can check/repair

2. ss switch also unplugs from harness. Follow the wire up to the connector which is kinda buried near fame and air box. Bypass to eliminate swtch resistance, if any.

3. Yes, I think you should perm compression test You heard an air whoosing pumping sound from the engine remember?

4. You can probably pull the the filler neck to re-attach the OPD (a black oval hollow plastic thing) but I would just pull the tank and go through the hoses, clean the ports ect. Easy to do after you've done it once. Draw the fuel circuit from tank to injector so that you understand it, also a simple affair.

It's difficult to tell what's wrong but start with the fuel supply and make sure that's right. Not much in the way of parts required. Keep compressed air away this time If you want to blow out the fuel distrib in the future just release an injec cap and blow with your breath in to the fuel dist inlet. Great for storage.

[dylanewilliams]

This evening I rebuilt the right throttle body. I ordered the throttle body rebuild kit from Bing. Dan Cata is $60 vs $120 for Bing, but I didn't want to wait twelve working days for it to ship from Romania. The shaft and and pulley are now one piece, they are no longer held together with a bolt. (BTW, my TB# is 75/45/104). Although the Bing website says they don't sell the bushings, they do. They wanted to scare you into buying the kit before the irreplaceable bushings wear, (just look at their website) but when people started ordering them from McMaster Carr, I think they got over it. To get out the bushings, I used a 3/8-16 tap, and when I got it into the bushing a decent amount, I inserted a 5/16 bolt(although if I did it over I'd have bought rod, not thread) through the other side bushing hole, which contacted the tap, and I gently hammered the rod, pushing out the tap and bushing together. I did kroil the bushings before I started and as I went.The rest was just as shown on Dan Cata's ADV page re the replacement, linked here

http://advrider.com/forums/showthread.php?t=630335

One thing to note, I didn't get a fuel injector gasket or a new c clip, although from what I can decipher, the invoice says they did. Check the contents when you get the package!

[def]

DW,

I hope your TB rebuild sorts your problem.

Good luck.

[biometrics]

you said you drained and cleaned the tank... but did you go back to the same gas source? In addition to your other issues, Maybe you have gotten some bad fuel?