ECM

[bradbates]

I'm brand new to Valkyrie's.  Specifically a 2000 GL1500 Interstate.  Do these rascals use an ECM?  I am experiencing roughness at constant throttle, and speed.  It idles and accelerates fine but it's at constant throttle it bucks. 

[sandy]

Yes there is an ECM. I doubt that's your problem. The carbs may have some gunk in them. Run the tank down to a couple of gallons and add a whole bottle of Berryman's B12. Take a drive at slower speeds and keep the revs down below 2500 for most of the time. Then get the carbs synched. The carb cleaner routine might have to be repeated. It took me six tanks to clean mine after buying my latest Valk.

[Hook#3287]

Bucks?  Slight or serious?

Our Valks use a ICM (Ignition Control Module) which in my experience has proven to be very reliable.

I would look to the carbs for the issues you describe, carb sync is what I'd look at first.

[BudMan]

In my world that used to mean Electronic Counter Measures.
I certainly hope I don't EVER need THAT again, especially on a Valk! 
Seriously, I expect the problem in the carb jets. Time and Berrymans, Seafome, Textron etc. will cure it or a real carb cleaning.

[Bagger John - #3785]

Before you sync the carbs, look into changing all the rubber hoses and vacuum caps on the intake runners if it hasn't been done recently. That way you won't be syncing against a vacuum leak.

[bradbates]

Some more detail.  It's hard to work full time and wrench on the bike.  It ran fine when I test rode it.  The issue developed somewhere on the end of the 80 mile ride home.  Same gas in the tank as when I bought it sol I don't think it's bad gas unless I got towards the bottom and sucked up something.  I did not hit reserve.  Reason I asked about the ECM/ICM whatever the hell it's called is I read a post about a sensor in the water pipe can cause what I'm experiencing.  I had an '08 Goldwing and had it torn down all the way to pulling the fuel tank so I'm fairly handy.  It's been a while since I've dealt with carbs and vacuum lines though.  I found the vac plugs on the carbs had hardened and cracked.  Made 3 news one and no difference.  Mine still has the smog crap near as I can tell.  Vacuum lines on #4 & #3 running up into the dark spaces under the tank.  I was wondering if one of the smog vac lines has gone bad?  I have poured a full can of Berryman's in about 1/2 tank of gas.  My thoughts are a fuel delivery issue in the petcock, vacuum issue or that water pipe sensor decided to shoot craps on me.  The thing idles and surges slightly but it's most noticeable above 2500 RPM.  When I grab a handful of throttle the thing goes GREAT!  Also thoughts on removing  smog stuff.  It appears it would eliminate some current (?) future  vacuum issues as well as clean things up a bit.

[Hook#3287]

Some more detail.  It's hard to work full time and wrench on the bike.  It ran fine when I test rode it.  The issue developed somewhere on the end of the 80 mile ride home.  Same gas in the tank as when I bought it sol I don't think it's bad gas unless I got towards the bottom and sucked up something.  I did not hit reserve.  Reason I asked about the ECM/ICM whatever the hell it's called is I read a post about a sensor in the water pipe can cause what I'm experiencing.  I had an '08 Goldwing and had it torn down all the way to pulling the fuel tank so I'm fairly handy.  It's been a while since I've dealt with carbs and vacuum lines though.  I found the vac plugs on the carbs had hardened and cracked.  Made 3 news one and no difference.  Mine still has the smog crap near as I can tell.  Vacuum lines on #4 & #3 running up into the dark spaces under the tank.  I was wondering if one of the smog vac lines has gone bad?  I have poured a full can of Berryman's in about 1/2 tank of gas.  My thoughts are a fuel delivery issue in the petcock, vacuum issue or that water pipe sensor decided to shoot craps on me.  The thing idles and surges slightly but it's most noticeable above 2500 RPM.  When I grab a handful of throttle the thing runs GREAT!  Also thoughts on removing  smog stuff.  It appears it would eliminate some potential vacuum issues as well as clean thing up a bit.

Bagger John is right, you should check all hoses and all vacuum caps.  Not a bad idea to check the carb air intake boots and clamps. 

Sounds like a vacuum issue.

Desmog is a way to avoid some of these vacuum problems.

I've done all mine and a couple buddies also.

[bradbates]

I ran across the post about the carb intakes boots and clamps earlier today.  I'll try that soon as I can.

Since it still starts well and runs I gotta think it's some little simple something I haven't discovered.  I'm a stickler for things working as they should, not kinda like they should.

[Bigwolf]

It could be the ignition control.....maybe.  However, I am going to agree with the others posted here.  Check/repair/replace all hoses and other sources of vacuum leaks.  Don't forget the intake O-rings. 

As for the ICM, the original factory units seem to be pretty trouble free.  There are some aftermarket ICMs around that are not so reliable.  I tried such a unit, a Dyna 3000.  When the weather got into the 80s and above, it ran just exactly as you describe.  Great acceleration, miss when cruising between 2000 and 3500, and a surge at idle.  It ran as it should when the weather was cold.

The ICM is under the left side cover and behind the coolant overflow tank.  The original will be black and held in place by a rubber boot.  If you find a blue one with 2 small knobs on top, then it is probably a Dyna.  The Dyna fits well in the original boot but should not be mounted that way.

[bradbates]

I got to wondering....if I do have a vacuum leak in chasing it down can I unhook the smog vac lines from
number three and number five, cap the nipple to determine if the leak is in the smog stuff?  Will the bike run with the smog stuff partially disabled?

[Hook#3287]

I got to wondering....if I do have a vacuum leak in chasing it down can I unhook the smog vac lines from
number three and number five, cap the nipple to determine if the leak is in the smog stuff?  Will the bike run with the smog stuff partially disabled?

You know, I've ripped 5 or 6 of those systems out, so you'd think I'd have a decent understanding of them, but nope.

My guess would be no,  there is a hole in the air box that gets plugged when desmogging, so that may prevent you from doing the test that way.

I'd have to do research to give you any help and don't have time now, but look here, may help.

http://www.valkyrieriders.com/shoptalk/smog.htm

[98valk]

I got to wondering....if I do have a vacuum leak in chasing it down can I unhook the smog vac lines from
number three and number five, cap the nipple to determine if the leak is in the smog stuff?  Will the bike run with the smog stuff partially disabled?

smog system only puts extra air into exhaust during decel. all other rpms it does nothing, so disconnecting will not affect running of engine.

[Jersey]

You can test the ICM using a basic VOM (volt ohm meter) and a Peak Voltage Adapter.  These can be bought at most places (harbour Freight, Amazon, etc.)  Or you can make the adapter if you have basic electronic skills.  check out this site:  https://thumpertalk.com/forums/topic/1034259-build-your-own-peak-voltage-adapter/


However, I just went through a similar deal as you're describing.  It was a combination of BOTH the Carbs being dirty AND the ICM not putting out full voltage.

'99 I/S

[bradbates]

I've had little time to work on the old girl but I wanted to ask you guys.  I hooked my Mighty
Vac to the line running to the petcock.  It would barely pull any vacuum and would not hold what little it did pull.  Petcock diaphragm?  I have a rebuild kit on the workbench and hope to get into it tonight.  I probably should hook the Mighty Vac to the vac lines on #3 & #4 for the smog stuff and see how they act too.

[98valk]

I've had little time to work on the old girl but I wanted to ask you guys.  I hooked my Mighty
Vac to the line running to the petcock.  It would barely pull any vacuum and would not hold what little it did pull.  Petcock diaphragm?  I have a rebuild kit on the workbench and hope to get into it tonight.  I probably should hook the Mighty Vac to the vac lines on #3 & #4 for the smog stuff and see how they act too.

only use a couple inches of vacuum when testing. not holding vacuum rebuild. once apart using an eyepiece u will see the leakage near the center.
the the PAIR valves there is a test in the manual. best thing to do is remove them. valves and all piping loses 3lbs of dead weight. california model with canister is even more weight removed.

[bradbates]

Couple inches of vacuum eh?  Good thing I have the rebuild kit because I put a bit more than that on the line.  

[Skinhead]

Remove, plug, and test the line itself to make sure it isn't the source of the leak before tearing into the petcock.

[bradbates]

Got the petcock rebuilt last night.  Looking at the old diaphragm I didn't see any obvious tears or holes.  It was kinda light colored around the rubber button in the center which I guess is where my leakage was.  I replaced the vacuum line and on Atticrat's suggestion I ran the line down to #5 for vacuum.  He said much simpler that way and he's right!  Hopefully this evening I can get the tank back on and fire the old girl up and see how she runs.  Fingers crossed!  I'm trying to get the old girl running right at least to get me through the rest of the season and this winter will tear her down and go through the carbs.  I still have yet to synch the carbs and that's on the "to do" list.  I'm still uncertain of which screw is used for the synch process.  I read that #3 is the cylinder to synch the others to and it has no adjustment.  Question is, where the heck IS the adjustment.  I read look for a blue screw.  I don't see any.  The clamps on the boots up under the gas tank were very loose.  I tightened the snot out of them so now all the intake connections are snug.

[bradbates]

Petcock rebuilt, new vacuum line on petcock, new plugs gapped to .035, new vacuum, intake boot clamps tight (all 18 of 'em), can of Berryman's in the tank, carbs synched, STILL surges at constant throttle.  One last thing to try is replace the ECT sensor.  Beyond that it looks like a carb overhaul.  At least I'm learning my way around the old girl...

[98valk]

Petcock rebuilt, new vacuum line on petcock, new plugs gapped to .035, new vacuum, intake boot clamps tight (all 18 of 'em), can of Berryman's in the tank, carbs synched, STILL surges at constant throttle.  One last thing to try is replace the ECT sensor.  Beyond that it looks like a carb overhaul.  At least I'm learning my way around the old girl...

surging?  up and down @ idle?  always indicates a vacuum leak. PAIR valve vacuum hoses know to leak over time.
at steady throttle road speeds, Pilot jets, let Berry work, also check needle slide diaphragm and PAIR vacuum hoses.
New manifold O-rings might be in order. OEM are Buna-N.  better find Viton.

[bradbates]

No, idle is pretty darn steady.  Surging is at speed, above and below 2500 rpm.  It's not a miss, more like lightly giving and dialing back throttle.  I have put the mighty vac on the vac line to the PAIR valve and no leakage indicated.  I have not capped the nipples where the PAIR valve vac lines connect to the intake tubes and test rode it.  I'll do that this evening and see how it does.  Manifold o-rings are ordered however, I see no evidence of leakage i.e. the coffee stains around the bottom.  Needle slide diaphragm?  Hmmm, I'm gonna need to research what that is.  Thanks

[bradbates]

Needle Slide Diaphragm. OK, got it.  Inside the carbs.  I think if this issue goes so far as to rebuild the carbs I'll pull them and take them to Atticrat for a good going over.  I talked to him the other day on the phone and I believe he has forgotten more about Valkyries than I will ever know.

[98valk]

did u determine as BW mentioned if your ICM is OEM or a Dyna?  Dyna's are known to slightly miss around 2k rpms sometimes. Mine does.

[bradbates]

Yes sir, Ignition Control Module is original.

[bradbates]

Well, I know a heck of a lot more about a Valkyrie today than I did a month or so ago.  I have the cuts and bruises to prove it!  I pulled the carbs and took them to Attic Rat to work his magic.  Great guy!  Dealing with all the other distractions it was a couple of weeks before I could get them in and then another week to get that cursed air box in!  :-).  Fired the fat girl up and she sang sweetly to me, that is until I got her out on the road and that cursed roughness at constant throttle is still there although, not as pronounced as it was but still there never the less.  I have synched the carbs, rebuilt the petcock incl. new petcock screen, new fuel lines, de-smogged, new plugs, replaced the ICM temp control sensor on the thermostat housing, new thermostat, coolant and upper and lower radiator hoses, K&N Air Filter cleaned and serviced, New throttle and choke cables, new vacuum line run to the petcock from #5 instead of #6 based on Attic Rat's suggestion and he's right, much easier routing.  New vacuum plugs and o-rings in intake tubes.  I'm starting to suspect the Ignition Control Module which I erroneously referred to in my subject line above as ECM meaning Electronic Control Modules and NOT Electronic Counter Measures as pointed out to me in an earlier reply to my post.  I talked to Attic Rat and he can't look at her until the first of October which I may just have to wait.  What the hell am I missing?  Aside from the ICM I have not checked the valve clearance.   I'd think if it was valve clearance I'd notice something off at any speed/rpm.  Yes?

[falconbrother]

My 1999 IS was hesitating coming off of idle.  I have run a can of STP's Seafoam knockoff and it seems to be clearing up.  I plan to run another can of STP through it as well.  The stuff is nearly half the price of Seafoam so, I run it through my Suburban as well. 

This IS has never been real smooth coming off of idle.  I will ignore that for now.  I think it has to do with the 4 inch exhaust that was on it when I got it.  I'd love to go back to a stock exhaust system, or at least one that wasn't as loud as this one.

[bradbates]

My issue is not coming off idle, it's at constant speed, particularly noticeable in the lower gears.  Acceleration is GREAT from any rpm.

[Blackduck]

Have seen the list of parts changed but did not see if you have changed the spark plugs.
May also pay to check the plug cap resisters and wires. Even for water or residue on the plugs from a blocked drain hole.
At constant cruise you will be at the leanest mixture which is the hard to fire.
Also check the connections on the coils, came up recently on here where someone found a wire with the terminal alongside the coil terminal, just held on by the insulating cover.
Cheers Steve

[bradbates]

Good tip on the coils.  I'll check them out.  My post was rather long winded, new plugs have been installed, the plug wells were clean and the drain holes are all open.  It could be plug wires, I reckon the only way to know is to change them out.  That looks like a bit of a chore.

[98valk]

Good tip on the coils.  I'll check them out.  My post was rather long winded, new plugs have been installed, the plug wells were clean and the drain holes are all open.  It could be plug wires, I reckon the only way to know is to change them out.  That looks like a bit of a chore.

oem plug wires have resistors installed plug end. check that end plug is tight.
also too much dielectric grease (does not conduct electricity) inside plug ends will cause mis-fires.

[Blackduck]

No need to replace wires to see if that is the problem.
Check them and the resisters with a multimeter.
The only thing the multimeter will not show is if the wire insulation is breaking down and the spark is dissipating through the insulation to ground. Have not had that problem with a Valk but did on an old GL1000. Only found it by chance, got home from work after dark and was looking around the engine in the dark and could see a glow from a lead. Just had a very slight miss that was driving me nuts trying to sort out.  New resistance cable and deleted the resisters and no more problem.
Cheers Steve

[Firefighter]

Seems your moving away from fuel to spark, right? Thinking after all the work and the fact that the bike always accelerates good then not fuel, correct? Probably right.

I know you replaced the fuel line, but wanted to add (if you don't know) these machines cant usually tolerate a added fuel filter or a fuel line that is too long or is not constantly going down hill. Usually at half tank or under will starve for fuel, sometimes the engine will die. Doesn't really sound like yours. Also, the fuel vent can cause similar trouble, some place a tie strap or similar under the fuel cap to see if it is a vent problem.

Ignition: One thought (2 cents) maybe, cause it happened on my 2000 IS, is grounds. The coils ground to the engine frame. The frame grounds to the engine via a wire, then the engine grounds to the battery negative via another wire. The ignition system requires a very good battery, mine with a bad frame to engine ground would miss at low speeds, coils were missing. With a weak battery the engine will spin like new but not enough voltage to fire the ignition (info). Check battery voltage at battery then test battery positive and negative to frame and see if they are the same. Long shot!

[bradbates]

No fuel filter other than the screen in the tank. It idles smooth.  I'm going to check the connections on all the coils. During the carb job the coil I loosened had som corrosion where it bolts to the frame and the attached ground connection.  I replaced the fuel lines with genuine Honda lines. I'm going to check the vent line too. I'm kinda stumped. I think it's something simple I'm missing. 

[Firefighter]

My meaning is not coil to frame ground connection but frame to battery negative connection. Take a battery voltage reading at the two battery terminals then leave the positive probe on the batt. positive and place the negative probe on the frame (somewhere like a bolt) and see if the readings are the same.

Like I said it's a long shot but it happened to me.

[bradbates]

Update.  Better but still not right.  At constant throttle both under load and sitting still there is roughness and small backfires in primarily left exhaust at in the 2500 - 3000 range.  I've had 1200 and 1800 wings but this is my first 1500.  The 1200 was carbureted but the 1800 was fuel injected.  I had Attic Rat do the carbs so surely it can't be a fuel issue but it sure acts like it to me.  Idle is pretty darn smooth and acceleration is very good.  I don't seem to notice the exhaust burbling at lower rpm's, below 2500 but I'm not one to lug an engine if you catch my drift.  I have checked over and over vac lines.  This goofiness wouldn't have anything to do the the de-smog job would it?  Like the gaskets on the bottom of the heads not sealed?

Another thought just came to me.  I have a K&N air filter and have the foam pad installed, could my issue be an air rather than fuel thing?

[Bagger John - #3785]

Another thought just came to me.  I have a K&N air filter and have the foam pad installed, could my issue be an air rather than fuel thing?

Put a new OEM air filter in the airbox and see if the surging persists.

[bradbates]

I'm going to pull the tank and take out that foam prefilter on the K&N and try it while the new original is being shipped to me. Will update. Thanks to all who have responded for your advice and wisdom.

[Firefighter]

I used to check different plug wires with a timing light to try and find a miss. Don't mean while your riding of coarse, but if you are able to create this miss, roughness, etc. on the side stand, might be able to rule out ignition, maybe in low light. Move from wire to wire and compare??

[bradbates]

Removed the foam K&N prefilter, took her for a spin last night, no joy.  Same 'ol same 'ol.  I can create the issue while the bike is on the side stand.  Mild popping/backfiring/burbling at constant throttle in the 2500-3000 range.  I guess next I will pull the K&N out and try an original paper filter and see if that makes a difference.  I serviced the K&N myself, could I have over oiled it?  If so maybe I just need to ride the old girl a long ways and see if things improve.

[John Schmidt]

I didn't go back and read all your posts on symptoms, but one thing comes to mind is the trigger wheel and the associated clearance between it and the pulse generators. One side might be a bit too wide, letting it operate rather normal at lower RPM but a bit wide to do so when running up higher. What you have described doesn't strike me as a fuel issue, sounds more like a faulty ignition problem when under stress of higher RPM. Might be as simple as a loosely seated plug wire in a coil, easily fixed. Might be a cracked resistor in one of the plug wires, easily fixed. If it were me(thank goodness it's not  ), I'd be tempted to pull each plug wire one at a time and measure the resistance on each to see if they all match....bike not running obviously. While checking each wire, give each one some good twists like a snake attacking a meal. Just a few thoughts passing through my addled brain.