Project CB1100F

MB-5 Joined: Mar 12, 2018 Posts: 23 Location: Western PA

Thanks for adding us to the forum. We had an opportunity to purchase a tired CB1100F that had sat for a number of years. The tank had serious rust in it and when I first put a battery on it, smoke was coming up from near the solenoid; yah buddy! Smile

I believe this will be a LONG term project but looking forward to it. Now I am going to start searching the tech forum...... lol

Posted: Wed Mar 21, 2018 10:20 pm

Looks to me like an 83 CB1100F, sir. Definitely worthy of a project! Welcome to the site, keep posting pics... we like pics!

FYI, on the left side of the steering neck is the VIN plate, that will have what should be the real model and year. I say should because it is possible to replace the plate (I just did it on my 82 900F, putting the same plate back on after powdercoating). If there's no plate, or the plate says something different than 1983 CB1100F, then the original VIN is stamped into the steering head tube, on the right side.

Posted: Wed Mar 21, 2018 10:28 pm

Nice find Springer 2!

I had that on my "to collect" list, had dug my trailer out of the snow, and was ready to collect it on Friday. Unfortunately, the seller told me someone (you!) picked it up already. Congrats on a good purchase.

It is definitely an '83 CB1100F, and has much potential. If I can be of assistance with the resurrection please let me know!

Enjoy!

Steve

MB-5 Joined: Mar 12, 2018 Posts: 23 Location: Western PA

SteveG wrote:

Nice find Springer 2!

I had that on my "to collect" list, had dug my trailer out of the snow, and was ready to collect it on Friday. Unfortunately, the seller told me someone (you!) picked it up already. Congrats on a good purchase.

It is definitely an '83 CB1100F, and has much potential. If I can be of assistance with the resurrection please let me know!

Enjoy!

Steve

It is most likely the same one, Milford, PA, which is just across the river from NY and NJ. It had been posted for a while and I don't know how much activity he had gotten about it. The seller was a very nice guy and he and his GF were so helpful. I appreciate your offer to help and your understanding about us buying it. Thank you.

Posted: Wed Mar 21, 2018 11:31 pm

Springer, I was a close third on that bike. I was going to make the trip when I get back from travelling for work. Oh well, it'll get some good love from a fellow forum member. Enjoy it!

Posted: Thu Mar 22, 2018 11:15 pm

Lattice rear-sets and everything! Great score.

MB-5 Joined: Mar 12, 2018 Posts: 23 Location: Western PA

Thanks for all the replies. I did get a couple of minutes to peel open the wiring harness to try to find what was burning. There is a large diode there and it appears to be shorted, less than 1 ohm in both directions. Looking at the wiring diagram also explains why the neutral light came on without the switch being turned on. The last owner never tried to start the motor as he got this in a 2-for-1 deal and really wanted the other bike; this one was just part of the deal. I mention that because all of the insulation is burned off the diode wire and it would appear that it was ridden for a while with the short to do that much damage to the wire. I do hope a new diode and wire will stop the smoking. All part of the challenge. Smile

Posted: Fri Mar 23, 2018 2:35 am

If there is current through the blocking diode then you should check the engine ground, that diode is only there to keep the neutral light from illuminating with the clutch lever closes the clutch safety switch.

It seems your starting current is being returned by that path with indicates a ground problem between the battery and the engine block. If you look at the right side, the battery ground should go to the frame and from there to the engine (carrying the high starting current). Almost any other electrical will blow a fuse.

Posted: Fri Mar 23, 2018 12:11 pm

Sillygoose, you are an electrical genius. Can I be your apprentice? Smile

Kidding, I hate electrical Very Happy

MB-5 Joined: Mar 12, 2018 Posts: 23 Location: Western PA

sillygoose wrote:

If there is current through the blocking diode then you should check the engine ground, that diode is only there to keep the neutral light from illuminating with the clutch lever closes the clutch safety switch.

It seems your starting current is being returned by that path with indicates a ground problem between the battery and the engine block. If you look at the right side, the battery ground should go to the frame and from there to the engine (carrying the high starting current). Almost any other electrical will blow a fuse.

Thanks a bunch, that helps. I did a quick check and the negative battery cable goes to the frame and to the rear of the engine. I just tried to wiggle the cables as I was pressed for time. Both connections appear tight but I am going to check resistance from the battery cable to engine to see if it is making a good ground.

MB-5 Joined: Mar 12, 2018 Posts: 23 Location: Western PA

I just noticed I put CB1100R instead of CB1100F at the top of the thread. Title changed to CB1100F. Thanks sillygoose for the help.

Posted: Sat Mar 24, 2018 4:42 am

There should be an edit button on your original post, from there you can change the title or edit the post.

Twinstar Joined: Sep 25, 2010 Posts: 238 Location: Vermont

Good score, I had been emailing the seller for weeks trying to get a response and would've picked that bike up also.... seems like there was quite a few of us after this one.

MB-5 Joined: Mar 12, 2018 Posts: 23 Location: Western PA

adk_finn wrote:

Good score, I had been emailing the seller for weeks trying to get a response and would've picked that bike up also.... seems like there was quite a few of us after this one.

I wanted a project and I am looking forward to this one. The seller is a great guy and it was worth the trip to go just to look at some of his bikes. He had a very nice Suzuki 2-stroke street bike along with a BSA and 2 Triumphs that look like new along with a number of nice Harleys. He just was out of room for the bikes.

Posted: Sat Mar 24, 2018 4:36 pm

Back to your problem. Only the starter motor is not fused, it is grounded to the cases so if the case ground is compromised then the high current will return via a different path, the clutch cable might be one way it works back to the battery but the large current means heating will be involved.

Most of the electrical circuits are protected by the 15A glass fuses so should blow a fuse if there is any kind of short that could result in heating.

A couple of circuits are only protected by the 30A main fuse, these are the starter solenoid coil and the regulator (used by the alternator to create the magnetic field). The starter solenoid actuator coil gets 12V from the start push button switch and requires a ground from either the clutch safety switch or neutral switch to complete the circuit and energize the solenoid. The return side of the actuator coil is directly connected to the clutch safety switch and one side of the diode, when neutral is engaged the diode is forward biased and it completes the circuit and allows the solenoid to be energized.

Since it appears the diode is heating up it carries a high current it was not designed for so I would start there. Assuming the bike grounds are ok (battery to the frame, frame to the engine case, harness to frame by the coils), I am thinking the starter solenoid is bad/damaged or the wire harness has been compromised.

I would start by removing the starter wire from the solenoid and seeing what happens. Of course nothing should happen but hearing the solenoid activated but if you get heating I would suspect the starter solenoid to be the problem. Electrical problems are often not obvious but if you tell us what is going on we can probably sort it out for you.

MB-5 Joined: Mar 12, 2018 Posts: 23 Location: Western PA

I checked the fuses, all check okay. The solenoid looks bad AND it appears like a pretty heavy wire is used as a fusible link. I ordered a new solenoid and it is here. It also has a 30 amp fuse in the new solenoid. The diode should be here next week. I am going to try some tests next week. sillygoose I greatly appreciate all of your help as well as the others here on the forum. I will let you know how it tests out. Again, many thanks.
Randy

Twinstar Joined: Aug 03, 2010 Posts: 258 Location: se pa

Randy, Lots of great guys here willing to help. When you learn how to use the ‘search’ feature, you can spend hours reading. Be sure to take notes or save them in your favorites. I have gotten so much help from toddk & many others. Don’t be afraid to ask.

Posted: Mon Mar 26, 2018 4:17 pm

Also check the neutral switch wire. Alot of times it can get pinched by the starter cover and short to ground.

Posted: Mon Mar 26, 2018 5:25 pm

1100russ wrote:

Also check the neutral switch wire. Alot of times it can get pinched by the starter cover and short to ground.

Time to wake from a long winters nap. Shocked

Grounding the neutral switch wire will only cause the light to turn on and allow you to start the bike in gear, when the switch closes it connects the wire to ground.

Posted: Tue Mar 27, 2018 3:27 pm

sillygoose wrote:

1100russ wrote:

Also check the neutral switch wire. Alot of times it can get pinched by the starter cover and short to ground.

Time to wake from a long winters nap. Shocked

Grounding the neutral switch wire will only cause the light to turn on and allow you to start the bike in gear, when the switch closes it connects the wire to ground.

Yep. Oops lol.

MB-5 Joined: Mar 12, 2018 Posts: 23 Location: Western PA

Thanks again for all of the help-it is much appreciated. The new diode arrived and testing it verified the original diode was shorted. My moonlighting job, the weather and a cold are keeping me from getting much done. I did manage to put sealer in the tank and it will be curing the next couple of days. By the time I get the burned wiring replaced, it should be more than ready for gas. Smile

MB-5 Joined: Mar 12, 2018 Posts: 23 Location: Western PA

I replaced the solenoid, the diode, and the burnt wiring. The one alternator brush looked like it was stuck all the way down and touching the housing so I cleaned that up and replaced the brushes. After all of that, still no change with the electrics. I used a battery charger this time so I could see if excessive current was flowing. With the switch off, the neutral light comes on if in neutral. Turn the switch to on and nothing changes, nothing electrical works, and the current draw is so low the meter does not noticeably change. I am questioning the ignition switch as I am running out of ideas. Any thoughts?

Posted: Mon Apr 02, 2018 4:59 am

For the neutral light to be on with the ignition switch off you would have to have power at the fuses. Also, since the neutral light and oil pressure light are connected together, the oil pressure light should also be on if the oil pressure sender is wired up and working.

For you to have power at the fuses with the ignition switch off you would have to have a bad ignition switch. In the off position none of the contacts are connected, for the neutral light to be on with the ignition switch off the switch must be bad.

Or your wire harness is toast, I happen to have a new 1100f wire harness if yours is beyond repair, PM if you wish to explore that option.

MB-5 Joined: Mar 12, 2018 Posts: 23 Location: Western PA

I am finding some of the electrical issues. Even with the ignition switch out, the neutral light comes on as soon as the battery is connected. I tried to disconnect the stator connector but it would not release. After some work it came loose but it was partially melted together. Despite that the stator actually checks out okay however the rectifier is toast. I started tracing the wiring out and while the neutral light comes on the oil pressure light does not. I took the cover off the starter and seen a replacement starter and the oil wire was very tight. I removed the starter and found the one wire was under the mount and nearly severed from the bolt and the insulation was gone where it was pinched. I will take care of that and see what is next. Love this electrical stuff...... Smile

MB-5 Joined: Mar 12, 2018 Posts: 23 Location: Western PA

Finally got a chance to work on the bike some. I found a number of electrical problems; repaired most and worked around 2 of them. Anyway the good news is it started! At first the system was not charging but wiggling the stator connector pictured above and the voltage jumped from 12.5 to 13.6. The burnt connector was not making good contact so it will be replaced. The engine has an intermittent miss but one of the coils is missing the screw cap and I just have the wire pushed in. I am trying to find one but not even exactly sure what it is called. A lot of work to do but it is a big lift to have it running. Smile

CB1100F Joined: May 13, 2005 Posts: 3249 Location: NE OHIO

Springer2 wrote:

Finally got a chance to work on the bike some. I found a number of electrical problems; repaired most and worked around 2 of them. Anyway the good news is it started! At first the system was not charging but wiggling the stator connector pictured above and the voltage jumped from 12.5 to 13.6. The burnt connector was not making good contact so it will be replaced. The engine has an intermittent miss but one of the coils is missing the screw cap and I just have the wire pushed in. I am trying to find one but not even exactly sure what it is called. A lot of work to do but it is a big lift to have it running. Smile

Stock coils ? send me an address and I'll send one .

MB-5 Joined: Mar 12, 2018 Posts: 23 Location: Western PA

Luckysox wrote:

Stock coils ? send me an address and I'll send one .

PM sent. Thank you so much!

Twinstar Joined: Sep 25, 2010 Posts: 238 Location: Vermont

It is good to see the update, thanks for sharing. I am happy to see that the bike landed in good hands. Post some pics of the bike for us to see when you get the chance.

MB-5 Joined: Mar 12, 2018 Posts: 23 Location: Western PA

Okay so it starts and runs now. When I took off the cover on the left side of the engine (where the ignition crank pick ups are) there was oil in there. Is that correct? I can find oil seals for the right side of the crankshaft but not for the left. Thanks in advance.

MB-5 Joined: Mar 12, 2018 Posts: 23 Location: Western PA

adk_finn wrote:

It is good to see the update, thanks for sharing. I am happy to see that the bike landed in good hands. Post some pics of the bike for us to see when you get the chance.

Will do. Still not much to look at yet as I had been working on the electrics so it looks the same, just fewer body parts on it now to access the wires. Thanks to all for the help.