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#1: starting issue 86 XV1100 (SOLVED) Author: wb1100,

Posted: Sat Apr 03, 2010 12:40 pm

I have a 1986 XV1100. The problem is that it won't start on it's own, but you can push start it. When I try to start it the bike it will turnover for a couple of seconds then stop acting as if the battery is dead. The battery is fine and does the same thing with the battery charger on it.
How I got to this point. A friend and I tore in to it and found the idler gear was pretty ground up. The gear wouldn't even engage to the flywheel it was in such bad shape. I took it to work and had a buddy turn down all the mushroomed end of the gear. I then put it all back together, the idler gear moves in and out of flywheel very smoothly now. I thought that we had fixed the problem but as I mentioned earlier now when I try to start the bike it acts like the battery is dead. We did all the basic checks the starter spins, the soleniod seems to be working, checked all the grounds.

My questions are:

Could there be something binding in the gears I thought I had fixed, that would draw that much power to stop turning over the motor?

Could the starter be worn out just enough to where it would act like this?

I know it sounds like it could be a grounding issue. I checked all the grounds, Is there anything I could be missing with this?

Any help would be much appreciated. Thank you! wb1100

Last edited by wb1100 on Fri Apr 16, 2010 12:50 pm; edited 1 time in total

#2: Author: Con,

Posted: Sat Apr 03, 2010 8:01 pm

1. pull your spark plugs out and see if it turns over OK. this will find any binding problems without stressing the starter too much.

2. Yes, replace the bushes and clean any carbon buildups.

3. did you check the +ve from battery to solenoid and solenoid to starter? Do you have a -ve from battery to frame and battery to engine case? Have you cleaned AND TIGHTENED the connections to the starter relay?

Are you sure the battery is OK? A battery charger can supply about 4A but a good battery will supply more than 200A during starting.

#3: Re: starting issue 86 XV1100 Author: eaglebeak,

Posted: Sat Apr 03, 2010 11:07 pm

From the symptoms you mention, your problem is low battery voltage that could be from (1) bad battery, (2) dirty connections as Con mentioned, or (3) a bad frame ground.

Since you can push start the bike, the ignition system and everything else is working. But, since the TCI (ignition module) must have at least 10.5 to 11 volts on it to work, cranking the starter with a weak battery drops the system voltage down enough to keep the ignition module from working. When you push start the bike, there's no starter drain and voltage stays high enough for the TCI to work.

After cleaning your existing battery and ground connections, do the "frame ground" modification that's outlined in the "tech info" section. The OEM system only has a battery ground cable attaching to the lower engine case, and the frame only gets ground through the complicated path through all the engine components to the engine mounts. Years of vibration loosening and mild corrosion eventually create much resistance in the engine-to-frame ground path which creates a low voltage condition to the ignition module, all accessories, and even the rectifier/regulator module (for charging the battery) that all ground to the frame.

Do the frame ground modification first, charge the battery overnight, and see if that's a fix. If not, we can explore a battery hydrometer check and checking the voltage regulator output.

#4: Author: wb1100,

Posted: Sun Apr 04, 2010 11:58 am

Thank you for all your ideas. I will try these and reply with what happens.

#5: Re: starting issue 86 XV1100 Author: wb1100,

Posted: Fri Apr 09, 2010 2:09 pm

I pulled everything back apart to check any binding issues. Decided to check the starter again, with the starter completely out of the bike. Put power to it with jumpers and the battery out of the bike. The starter spins fast at first and then starts slowing down on it's own. I then tried with a different battery and was told to try it with a battery charger since it has constant power and it does the same thing.

Shouldn't the starter keep spinning at a constant speed and not slow down?

Today going to do the ground mod and make sure all the power from the battery is getting to the starter.

#6: Author: Aussiexv1100,

Posted: Fri Apr 09, 2010 4:21 pm

I would check the condition of the starter motor brushes and commutator while you have it out of the bike.
Aussie

#7: Author: wb1100,

Posted: Sat Apr 10, 2010 12:00 pm

How do you know if the brushes are bad?

#8: Author: 1986 XV700,

Posted: Sat Apr 10, 2010 12:38 pm

They will be too short.
From Chapter 7 of the Clymer Manual:

3. Pull back the brush springs and remove the
brushes from their guides. Measure the length of
each brush with a vernier caliper (Figure 52). If they
are worn to less than 0.33 in. (8.5 mm), replace them.
4. Check spring tension. Replace springs if their
condition is in doubt.
5. Inspect the commutator. The mica in a good
commutator is below the surface of the copper bars
(Figure 53). A worn commutator is indicated by the
copper and mica being level with each other. A worn
commutator can be undercut, but it requires a specialist.
Take the job to a dealer or electrical shop.
6. Inspect the commutator bars for discoloration.
Pairs of discolored bars indicate grounded armature
coils.
7. Use an ohmmeter to check continuity between
commutator bars (Figure 54). There should be continuity
between pairs of bars. Also check for continuity
between commutator bars and the shaft
(Figure 55). There should be no continuity and if the
test indicates continuity, a short is indicated. If the
armature fails either of these tests, the starter should
be replaced.
8. Inspect the field coil by checking continuity from
the cable terminal to the motor case with an ohmmeter;
there should be no continuity. Also check from
the cable terminal to each brush wire; there should
be continuity. If the unit fails either of these tests, the
starter motor assembly must be replaced.

#9: Author: wb1100,

Posted: Sat Apr 10, 2010 12:46 pm

Thank you VX700 I have a haynes manual, but couldn't find as much info as you just gave me.

Do you know if the starter should turn over at a constant speed?

#10: Author: 1986 XV700,

Posted: Sat Apr 10, 2010 1:01 pm

If its not trying to turn the engine over it will be constant. If it is turning the engine over it will pulse a little during the compression cycles of the cylinders. If it or the battery is weak then the pulsing will be much more noticeable.

#11: Re: starting issue 86 XV1100 Author: greenagain,

Posted: Mon Apr 12, 2010 12:53 am

eaglebeak wrote (View Post): ›
After cleaning your existing battery and ground connections, do the "frame ground" modification that's outlined in the "tech info" section.

I've looked high and low for that article, but I can't seem to find it confused

#12: Re: starting issue 86 XV1100 Author: eaglebeak,

Posted: Mon Apr 12, 2010 8:36 pm

Unless someone has already changed things, there's usually only one ground wire leading from the battery's negative (-) terminal going straight down and connecting to the right rear portion of the engine case. Ground path to the frame must go clear through the engine and make though its mounts or other components that attach to the frame. Years of vibration and mild corrosion can easily result in quite a bit of voltage drop between the battery and frame.

Usually the flat bar under the seat which is welded between the upper frame tubes (some relays are mounted on it) is a good place to make the ground point. Drill a 1/4" hole through the bar, but make sure any cables under the bar are shielded with something to keep the drill bit from going through them. Scrape all the paint off down to bare metal for about 1/4" distance around the edge of the hole.

Use the same gauge wire (same size) as the OEM battery ground cable and make a new ground cable (with heavy wire lugs crimped or soldered to each end). The new cable will be bolted tightly to the flat bar with a bolt through the hole you drilled. The cable length will depend on whether you want to hook it directly to the battery's negative post along with the OEM cable (gets crowded), or run it down to connect under the same bolt on the engine case where the OEM cable is hooked. Clean all terminals and tighten everything securly.

The new ground now directly hooks the battery negative to the frame to fix any problems caused by poor ground to many components that use only frame ground. The OEM cable remains on the engine for best starter motor ground.

#13: Author: wb1100,

Posted: Fri Apr 16, 2010 12:59 pm

I ordered a rebuilt starter online. I put the new starter in and slapped everything back together and she fired right up!!!!!

I want to thank everyone for all their help.
wb1100

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