Rear cylinders not firing

[DWD6955]

Gentlemen, After cold starting 2005 xv1700a my rear cylinders (assuming 2 & 4) suddenly stopped firing. After checking connections, re-starting and testing again the cylinders once appeared to fire then stopped again. Obvious! I’ve checked ignition coil primary and secondary resistance and pick up coil resistance, every connection I could trace and they are within specs. Visually inspected wiring but did not continuity test wires. Primary and secondary wires lead to ignition unit according to wire diagram. Where is the ignition unit on this bike? I guess I need to check continuity but Not sure where to go from here. Please help if you can. I’m stuck! Thanks

[DWD6955]

Update, I located the ignitor unit or what we call computer for ignition. It’s behind the battery box. Would anybody know how to test it? An OEM unit cost $750, want to make sure it’s bad first.

[roadiemort]

http://www.werder.ee/Manual/XV1600.pdf

[roadiemort]

7-47

[DWD6955]

Thanks but I have the Clymer manual. They don’t instruct on how to test the ignitor unit. Still looking for help if anybody knows. I’ve tested ignition coils and pick up coil and they are within spec but can’t confirm if my ignitor unit is bad. The book calls it OEM term an ignitor unit, I think roadies know it as a control module or ignition computer. Example of the unit is the Dyna 3000. Attached pics. How do you test OEM module?

[roadiemort]

I take a buddy's unit out and put it in mine easy peasy. 1700 don't mix with 1600.

[DWD6955]

I like that manual though. Thank you!

[DWD6955]

I had issues getting the battery box out. The module is mounted on the back of the battery box and hard as hell unplugging the three harnesses that connects to the module. Had to remove fuse box, starter relay and box that contains those two components. There is no other way to get the module out except for pulling the battery box out. I tried like hell and it’s a pain in the ass. Of course unless I missed something. Took about 2 hours but I got the darn thing out. I just have to find the testing process for the ignitor unit. I would be pissed if I paid out $750 for a part and mine was good. I have no other indications of what could be bad. Will have to test the ignition wires continuity for sure. That’s another thing, can’t test continuity without pulling the ignitor unit. Sucks

[DWD6955]

Hey Roadiemort, 7-47 is fuel pump system right? Just want to know if I’m reading manual correctly. I really like that manual though!!!

[Father Pobasturd]

There's only one rear cylinder and one front cylinder. Two spark plugs per cylinder. It's a V-Twin.

[DWD6955]

Ok what would cause the back cylinder not to fire. The coil is good.

[DWD6955]

Could the ignitor unit cause the rear cylinder not to fire?

[DWD6955]

Right, I’m not thinking straight. Definitely feeling dumb, don’t know how to test the ignitor unit. May have to take it to a dealer to check that.

[DWD6955]

How do you know if the decompression solenoid is bad? Wouldn’t both cylinders not fire? Shit!

[DWD6955]

It sounds like it could be the ignition module but I don’t know how to test it.

[Father Pobasturd]

Checked plug wire for continuity?

[DWD6955]

Will make sure I do prior to purchasing ignition module. I checked cap and it was ok. Thanks FP

[DWD6955]

Darn shame I can’t test the ignitor unit I have but all indications are that the it’s bad. 53k miles and recent upgrades would make sense. New cobra slip ons and intake was probably too much for the old ignition module. The bike was running great then all hell broke out. It was intermittent. I Hope I didn’t miss anything, the aftermarket Dyna 3000 cost $320.

[Lug Nut]

You're modifications have absolutely nothing to do with your igniter box not working. I would look on eBay for a used one or see if anyone in your area has a 1700 2004 through 2007 (The igniter box on the fuel injected 2008 through 2014 models are differents than 04-07 carb ones) It's pretty rare for the igniter box to go bad. Have you used a temperature gun to make sure your rear cylinder and exhaust are not firing/cold? The igniter box is a pain in the ass and a knuckle scraper to get out isn't it? Lol the Dyna unit is nice for sure and cheaper than OEM and they work well.

[Lug Nut]

If you join the roadstar Clinic site on Facebook there is also a for sale parts and bike section on Facebook. I would bet you could find a stock 2004 to 2007 igniter box from where someone had swapped it out with the dining unit. Probably get it pretty cheap

[DWD6955]

Can I test svs with a meter? you would think if it was svs it wouldnt stop suddenly while idling, right? Bike has 53k miles on it. This is exactly what happened to get to this point....A couple weeks ago i cold started bike, it idled perfectly then same issue, while idling the rear cylinder suddenly stopped firing. Let bike sit a couple hours, started it again and it ran perfect for about a couple weeks. 2 days ago started bike and same thing happened but never recovered. i proceeded with ignition system testing process with my meter checking resistance, inspecting wires, moving wires around and making sure all connections were tight. Started bike up again but still firing on front cylinder only, but this time the rear cylinder tried to fire for a split second then stopped, didn't touch a thing, did it on its own. I have the ignitor unit out trying to figure out how to test continuity on terminals. So far i found 2 terminals to be open , no resistance. according to the wiring diagram rodiemort sent me the pins identify as the coil pins. still unsure of module testing process. i am going to recheck continuity on all ignition system wires one more time before i take the plunge and buy a Dyna 3000. if anything the bike will run better after i figure out WTH is wrong. if you see anything i may have missed let me know. Thanks Lug Nut

[DWD6955]

I got away from FB and Twitter. Too much drama for me! lol

[davej]

I think to check you might want to check the coil input voltage and ground signal. Did you pull the sparkplug and see if it is just carbon fouled? also make sure the plug wires on the rear cylinder are on the proper plugs. Other than that to check the module you would need to check the inputs and outputs right on the module. I don't have a clue where to find that info. If you decide to but a new module either buy a used one or buy a dyna 3000. neither are even close to the price of a new OEM module.

[DWD6955]

I can’t find that CDI testing process anywhere either. I read on the manual that it has to be sent to the manufacture for testing. Yah right! Not getting positive feedback from dealership either for testing CDI out of the bike. Basically it consist of capacitors and resistors maybe a transformer. Can’t even find an electronic diagram for the CDI.

[DWD6955]

I did check the coil and plug wire resistance but not the voltage to the coil. Plug wires are in correct position. The red/black lead from the coil goes thru a relay on the right side of the bike opposite of the fuse box. Also I’m assuming the voltage input is good because the same ground and hot lead go to both coils. That’s if I’m reading the wiring diagram right and I traced all the coil wires. I found that out by striping the wire harness shield, checking for continuity. All wires are good. Coils are carbon fouled probably due to idling too much. I ordered new plugs, wire harness shield and the Dyna 3000. I only seen one forum post where the ignitor unit was bad. They called it CDI But being that 53k miles on the bike, it may just have given out. Anything is possible. Any recommendations for Dyna 3000 settings Dave? Rev limit and curve setting? I don’t know much about them.

[davej]

dyna 3000 settings should be

sw1 off
sw2 on
sw3 on
sw4 on
sw5 off
sw6 on

that will set it to 5000 rpm and 32 º advance

If the inputs on the coils are correct then the CDI is OK. If the inputs at the coils are not OK then there is either a wiring issue from the cdi to the coils or the cdi is bad. If the rear plugs are carbon fouled then change them or clean them. I clean plugs by spraying with starting fluid or carb cleaner and then heat them with a propane torch until the carbon burns off.

[DWD6955]

I would have to re-install all components to check the inputs to ignition coil so I jumped the gun and went ahead and ordered new Dyna 3000 anyway. I will be sure to check inputs after everything is installed again. What else besides CDI or wiring could cause coil not to fire cylinder? I checked 3 times the continuity of orange lead, red/black lead and plug wires and all ok. The red/black wire on coil leads to a relay on opposite side of fuse box side. I’m assuming that relay provides power to both coils without checking wire diagram. What leads should I be checking on the coil for input? Orange to ground? Red/black to ground? The rear cylinder coil has the 2 leads orange and red/black plus of course plug wires. Does the bike need to be running or just key on to check inputs? Not sure of that process. I think I understand the ignition system sequence but not sure when power is applied to the coil. I’m thinking after starting the bike, would make sense but I’m not sure. Pretend I’m dumb, which I am. Lastly, is it possible that the ignition coil for rear cylinder can still be bad even if all resistance checks are to spec according to tables? The front and rear plugs were all carbon fouled evenly so I’m thinking that is not why rear isn’t firing.

[DWD6955]

Thanks for the info Dave. I just ordered new plugs, they are cheap enough. Hey Dave, will having aftermarket exhaust pipes, larger air intake and stage 2 jetting make a difference for Dyna settings? Just asking.

[davej]

jetting will make no difference on the settings. If front and rear are equally carbon fouled I would be looking into the fuel delivery a little more. (jetting and carb issues) but before digging into that replace the stuff you have ordered and ride it. If it turns out that your old CDI isn't bad you can always sell it to recoup some of the cost of the new one. People with 1600's will even buy a OEM 1700 CDI to raise their RPM from 4250 to 4750. A used OEM 1700 CDI is easily worth $100-$125 and will sell quick at that price.

[DWD6955]

Good point! eBay lowest price I seen for used CDI was $325. I would not sell it at that cost though. I honestly hope it is the CDI do I can move forward. How do I check input to coil Dave? Orange and ground with meter set to dc voltage? And does the bike need to be running?

[davej]

not sure of the colors but one should be battery voltage and the other should be modulating ground with bike running.

[DWD6955]

Dyna 3000 switches below in picture

[DWD6955]

Switch 7 & 8 are typically not useable or active on the stock Rodie are they. Am I correct by saying retard switches are usually used for a nitrous set up and I would have to modify wiring for TPS?

[davej]

7-8 are not used

[DWD6955]

Thanks for all your help, I will let you know after I put it back together what the conclusion is. Too cold to work in the shed today. Below 32 deg. This weekend it’ll be warm enough to ride and test. Again, thank you!