New guy needs help. 2nd time bike died while riding

[strappinglad]

Hi All! I've been snooping around the forum for the last few months reading up on the 650. I bought '78 Special in Oregon a few weeks back and rode it home to Las Vegas. It did an 800 mile journey without a single problem.

Now I can't ride for more than a couple miles before it dies on me. Two fridays ago, I put on a new cherry bomb muffler and took it for a spin and 2 miles from the house the bike just died while crossing an intersection. Electric start would crank over, but seemed like no spark. Tried to kick start... nothing. Tried every trick I knew to get it going, just dead. I pushed it the two miles back to the house.

From what the symptoms told me, I figured the coil died on me. I ordered a new coil from MikesXS. After 10 long days of waiting it showed up today. I was THRILLED to see my $70 coil was made in Taiwan and no markings to indicate + or - on the coil spades. I cleaned up some ground connections, slapped in the coil and the bikes fired right up. Success!

I ride the bike around the block to bed the new front pads. (Since I had so much time before the coil came I went through the entire front end.) The bike was running fantastic. Soon after I head over to my buddies place to talk bikes and hang. The bike just dies while going down the road. Exactly the same thing as last time and a couple miles from my house. My buddy is nice enough to bring his truck and ramps. While I'm waiting I try to start it again and it fires up and runs for about 15 seconds and dies. Now it is completely dead I'm sure.

If the coil is fired again I blame MikesXS and that POS expensive Taiwanese made coil! I'm not sure what is going on other than no spark. The plugs look good, caps and wires were replaced with the coil. Studied the harness while replacing the coil today and everything looked good. No bad connections or damaged wiring. No blown fuses and connections are clean.

The bike is fitted with an old Allison/Crane XR700 electronic ignition. It's pretty simple, fool proof, and I figure if if it wasn't working correctly the bike wouldn't start, even with a new coil.

Is it possible to plug the two wires into the coil incorrectly and have it fry? It seems like if that were the case, it wouldn't run at all or it would have burnt out much sooner than it did. I really don't want to buy another coil... I'm already pissed at MikesXS for taking so long and all the parts they send me seem to be such poor quality.

Any advice is appreciated! Not being able to ride just makes me depressed!

Thanks Gents!
Rusty

 

[peanut]

have you tested either of the coils ? there is a simple test which you should have done before ordering a new coil to be sure that it is the coil that is at fault.
Heres a link to a typical video guide . Also check the excellent technical section on this forum

http://www.dansmc.com/electricaltesting.htm

Are you sure that around the time you fitted new exhausts that you didn't adjust, tweek or fiddle with anything else ?

The fact that it starts and runs normally for a short while suggests a basic problem that possibly may be related to heat .

The only other thing i can think of that could cause an otherwise normally starting and running bike to cut out after a short time is if the gas tank is not venting and a vacuum is building up preventing fuel flow ? i know it sounds like a long shot but try run the bike with the filla cap off see what happens ?

 

[strappinglad]

I'll pick up an Ohm meter tomorrow to be sure. Lots my old one in a move.

But no, I didn't mess with any electrical related bits when putting on the muffler. I cleaned the carbs after I bought it, no adjustments, just cleaning. I've put down a few hundred miles since I took them off for a cleaning. It runs amazing when it starts, idles smooth, pulls hard, everything works.

I was also thinking it might be heat related... The coil getting too hot? The ignition? Wires? The bike never died while sitting in traffic. Only on the move.

 

[strappinglad]

........

 

[retiredgentleman]

If the bike still has the original fuse panel (4 position glass fuse type), replace it with new automotive blade type fuse holders. Solder and use heat shrink insulation.

 

[Tomterrific]

It's not the coil. With the meager info you gave and the experience of XS650.com you can pretty much figure out that the battery isn't being charged. It could be other stuff but the charging system would be my first guess.

Charge the battery and start the bike.

A field test to see if the headlight gets bright with a throttle blip from idle. The headlight gets brighter means the charging system is putting out enough charge to keep the battery up. Use the brights and hit the brakes so you're sure plenty of current is being used. I do this when I'm riding home at night. Trunk lids of the car in front are great but your garage door is good too.

You can use a mulimeter to test for voltage at the battery.

Tom

Edit: Oops! I read your post wrong. I see you state the starter montor spins the engine as normal not doesn't work which is what I was thinking. I leave the advise but the battery should be charged if the starter motor is working.

 

[freddy3]

How old is the battery and what voltages are you getting (at the battery terminals) with the bike idling?

 

[strappinglad]

A field test to see if the headlight gets bright with a throttle blip from idle. The headlight gets brighter means the charging system is putting out enough charge to keep the battery up. Use the brights and hit the brakes so you're sure plenty of current is being used. I do this when I'm riding home at night. Trunk lids of the car in front are great but your garage door is good too.

You can use a mulimeter to test for voltage at the battery.

Tom

Edit: Oops! I read your post wrong. I see you state the starter montor spins the engine as normal not doesn't work which is what I was thinking. I leave the advise but the battery should be charged if the starter motor is working.

Yes, when it idles the head light will get brighter after revving the engine a bit. I'll do some readings with the multimeter today and report back.

Thanks again for your input guys.

 

[Paulrxs650]

Hi

Change you plugs leads out. I had a very similar problem and spent a small fortune replacing coils, batteries, wring and even ignition system! Eventually realised my stupidity and chaned the leads. Quick simple fix!

Best regards

Paul

 

[strappinglad]

Alright! Made some progress for the little time I had. I wired in a new modern fuse block and rerouted some wires to keep them away from the hot bits. It fired right up! I didn't run it very long, but its working. I put a multimeter on the battery before I tried to do anything to the bike and it showed 12.7v. I'll do some more checking on the charging system tomorrow.

 

[strappinglad]

I got to run the beast around the block today to make sure everything was tip-top. Charging system looks good. (about 13.5v when running) Everything looks good, but I probably won't take to far from home for the next few rides in case I have to push it home again.

Thank you all for the suggestions, comments, and getting me back on the road. I think Hugh's PMA will be my next upgrade when the time comes.

Cheers!

Here's a shot of my beast in progress.

 

[peanut]

looks stunning.The drilled disks look great are they standard disks that have been drilled ? or are they off a different model/bike ?

 

[XSLeo]

13.5 volts at what rpms? That is ok at idle but at 2000-2500 rpms it should come up to 14.5 volts and not go any higher at 5000 rpms.
As far as the coil being made over seas, most are. They can be made over there much cheaper than they can be made in the states.
I as well as many other run Mike's coils with out trouble. By the way never heard of an Allison/Crane XR700 ignition. Sounds like something for a Harley.
Leo

 

[strappinglad]

The PO owns a machine shop so he went a little crazy with the drill press when he did the discs.

13.5v at idle. 1100-1200 rpm. I'll hold the revs and see where it stops.

The ignition setup being for a Harley would make sense. He did have a couple old Harley's sitting in the garage too.

 

[Stigda]

Hi, just an idea. Disconnect a gas tube and let gas flow into a bottle. If it runs nicely, test th other side.
If only drops come slowly down, you have to clean youre petcocks, that happened ut me. Good luck!