Neglected Basket Case Rescue

[Adamdrives]

Hey all, looking for some guidance on my 90 FJ1200.

I picked the bike up with 6700 miles here in California. According to the paperwork that came with the bike, it was imported from Mexico. At the time of purchase the bike started and ran, but poorly. The owner said he used to ride regularly, but due to an injury he wasn’t able to ride and hadn’t been on the bike for a year, but had started it once a month or so. I figured that the carbs just needed cleaning, my Bandit 1200 has done the same after sitting. The mileage seemed so low that I didn’t think there would be any large issues.

I trailered the bike home and got to work sorting it out. A few of the carb overflows were leaking when the bike was running. The PO had installed a Napa fuel pump with a mess of hoses, and the airbox couldn’t be installed. I replaced the pump with an oem style off eBay, and all the hoses with clear. I rebuilt all the carbs and replaced the needle jets, which solved the overflow issue. One carb had a missing washer on the main jet, and one pilot screw was missing the tiny washer. In short, the bike did not seem well maintained.

I installed the airbox using the subframe bolt trick, synched the carbs, and she idled pretty smooth and well. I checked oil level, which was above max on the sight glass. When I drained it, it smelled very, very gassy. I suspect fuel had been leaking into the cylinders for some time. I put in fresh and took her on a first ride. The bike was no longer leaking fuel, but wasn’t particularly rideable. Power felt very low. My Bandit is listed as 100hp stock, and with a dynojet kit in it, I estimated it was close to 130, and this felt much, much slower. It seemed to get better wide open about 7k or so, but had no low or mid punch, like I expected from a sport tourer.

I pulled the plugs and all were wet and dark. I verified spark was present on all 4, and cleaned then throughly. I ohmed the coils, and got readings of 2.25 and 2.15 ohm, slightly lower than 2.4 minimum spec according to my Clymer. When I tested the pick up coil, it ohmed low. 20 ohm or so, with spec being 149-182 for the DCI. The bike didn’t feel like it was missing, just low on power, but I replaced it anyway, verifying the new unit was within spec. There was no change in low power, so I took it on a longer ride to get it properly hot and try an Italian turn up to shake off the cobwebs.

On the ride the bike seemed like it was clearing up, but once it got hot in some stop and go it would completely die out and come back, constantly. The bike was completely shutting off in an instant, tach dying, then bump starting itself back to life. It seemed worse under higher load, but did not die once I came to a light. I put the high beam on while I rode and watched to see if the indicator light would go out when the tach died, indicating main power was going out. It stayed on, so I figured it must be ignition only.

Today I took most of the fairings off and checked the main ground, connections were clean on both ends. I tried wiggling any connector that might be on the ignition circuit, and couldn’t get the bike to die. The bike will start in neutral without clutch in or kickstand up, but won’t start in gear with kickstand down and clutch pulled in. I can hear the clutch switch clicking. I would expect it would start in gear or with kickstand down as long as clutch is pulled in, all my other bikes have been that way, but I’m not sure. The diagram is very crowded and hard to read. I may try making my own when I have more time, or if I really get stuck.

However, once I started bouncing the bike up and down, I could get it to die. At first it seemed like the rear of the bike was the source of the issue, But no matter what connector or part of the wiring harness I disturb, it stayed running. I noticed that the tail light and headlight both were flickering slightly, like they had poor grounding, but neither connector was damaged or improved from cleaning. The bike does charge and the battery tests OK. Voltage drop from frame to battery is 200mV or less.

After 30 minutes or so of idling the bike and trying to make it die, it started the smell…odd. Rich, but also just bad. During the process I put an infrared camera on the header pipes, and all were evenly hot, but when I put the camera on the oil cooler, it read out at 225 F. Coming from automotive, that seemed hot, so I put it on the cylinder head, which read 340+ degrees F. That’s too hot, isn’t it? Is it just because the bike has no airflow on an oil cooled motor? My bandit has never felt that warm, but I may have never idled and revved it indoors for as long, with little airflow.

Question 1: Any ideas on what seems to be ignition cutting out? I’d like to check the DCI ground, but the diagram doesn’t show where it is and I can’t tell. I may try cutting the wire and running my own. Clymer troubleshooting also says the check the “ignition ground” but afaik the coils are grounded through the DCI. Is the clutch switch behavior normal? I’m not sure how it interacts with the kickstand and neutral switch. Clymer tells me to check that, but doesn’t give any clues on what to look for.

Question 2: Is the bike is overheating? I’ve never dealt with this in a motorcycle, coming from automotive where everything is water cooled and has a gauge or warning light. You can really feel the heat rising up past the fairings though, it doesn’t seem right. This is in 70-80 degrees ambient temp here in Bay Area California.

The low power is also an issue, but I have a feeling it’s a symptom of whatever is going on with ignition. I’m also going to replace plugs, they had to be ordered and just came in, although I don’t think that explains ignition cutting out.

Thanks for reading. This issue seems to have been discussed a few times, but I haven’t come across any threads with a resolution. This bike has been much more of a project than I anticipated. Beyond engine issues it needs front rotors, fork seals and tires. Based on its condition, I think the seller was not honest about the bikes history. I think it’s been sitting for longer than a year, and wasn’t regularly ridden before that.

[balky1]

Jetting info of the carbs would help a lot.
If the rotors were bad, that bike has a lot more than 6000 miles, more like 106000.

[fj1289]

I'll second carbs.   (Carb problems offer masquerade as ignition problems - and vice versa).  The carbs need to be THOROUGHLY cleaned.  It takes most people three tries to clean them as well as they need to be cleaned - especially the idle and low speed circuits! 

Then get the carbs assembled correctly!  Not sure what the PO did - but for the bike to be right, it has to be right!

Carbs need the o-rings replaced - old dry o-rings will let fuel leak around the needle seats.  http://rpmracingca.com/proddetail.asp?prod=carbkit



http://rpmracingca.com/index.asp is your go-to for all things FJ.  Randy and Robert know their way around these bikes and engines extremely well - and are a direct importer with Yamaha - and have even been able to get a few "discontinued" parts "re-continued". 

I'm pretty sure Randy said they run these engines into the 400 degree range in the legend and roadster race cars.   The car racers are way more brutal on these engines than anything you can do to them on a street bike ... long stop and go traffic is the closest you can come to the abuse the cars deal out.   

Check out the Files section of the forum - ton of great info there. 

Other things to check on a new-to-you bike are the generator connector and voltage regulator and battery condition.  I had a couple bouts of ignition issues that were battery related.

Good luck!

[Adamdrives]

Thanks for the replies. The carbs are stock, although the main jets are 115s, not 112.5 like Clymer says they should be. I cleaned them well (but only twice so far  ), but I have considered taking them to my local shop to take a bath in the ultrasonic cleaner. I did replace the needle sets which fixed an overflow problem.

I could be wrong, but I have a strong suspicion this is an ignition issue. The bike completely shuts off for a second, there's no gradual loss of power. I'm going to try a new battery.

When I rebuilt the carbs, the only o-rings I found were around the needle valve set and pilot screws. I see the RPM kit has 16 "fuel transfer o-rings". I'm curious where those go, I dont see them in my diagram.

If this bike did roll over the odometer, that would really be dissapointing.

Thanks again

[RPM - Robert]

I see the RPM kit has 16 "fuel transfer o-rings".

If you didn't see these you didn't clean your carbs properly. These are for the transfer tubes in between each carb body. You need to break the entire carb bank down in order to get any cleaner out of the choke plungers, transfer tubes , etc, etc.

[Adamdrives]

I see the RPM kit has 16 "fuel transfer o-rings".

If you didn't see these you didn't clean your carbs properly. These are for the transfer tubes in between each carb body. You need to break the entire carb bank down in order to get any cleaner out of the choke plungers, transfer tubes , etc, etc.

Good to know.

[Adamdrives]

Spent some time with the bike tonight after work and verified with a meter that the coils were losing power when the bike was bounced up and down as I suspected. After taking all the fairings off and wiggling every connector and part of the harness, I couldn't get the bike to stall. In frustration I went to turn the bike off and knocked the key with my hand, and the bike stalled out for a moment. I wiggled the key, and sure enough, the ignition cylinder was slightly loose and would cause the bike to die when it was moved  

The irony is one of the first parts I ordered for the bike was a new tumbler because it would not turn into the "lock" position. I never got around to installing it because it wasn't a priority. For now I tightened the screws on the tumbler and I was able to ride the bike home for the first time. Still low on power, so I'll need to give the carbs some more attention, but I'm glad this part of the process is finished!

[Adamdrives]

With the bike now rideable I'm feeling better about the project. Hunting this cutting out issue was driving me up a wall.

I finally got around to picking up a fresh air filter and plugs from my local store. Turns out the bike had DPR7EAs in it. I got the correct DP8EAs in, I assume the R in the old plugs means they were resistor style, maybe that was giving me weak ignition. Anyway I synched carbs again (gained 3" vacuum from last time) and the bike is finally making power. Enough power to make it obvious on the first proper ride home that the clutch slips in 3rd gear and above   Still, it's nice to be able to feel the potential. Bike has some vibrations but I like how quiet it is when cruising. Bottom end is a bit soggy, I need to go through carbs again and check emulsion tubes for wear, but I can tell it wants the scream as the RPMs pick up.

The PO really didn't take care of this bike, and clearly was not honest about its history. Oh well!

I really need to get new tires, I was warned it would be difficult with the rear but I didn't realize there are no more radial options as far as I can tell. Looks like the Pirelli Demons are the best choice for cornering performance. A little more than I'm used to spending. Also considering the gsxr 750 17" rear upgrade if I can find a good deal, need to do more research.

edit: got onto my desktop and searched the forums for keyword "tires". Found someone in 2017 mention Shinko 016s in radial for front and rear, checked cycle gear and they have a Shinko 011 not sure how I missed that, I spent about an hour googling on my phone.

[mike g]

aVON RADIALS ARE GOOD

[melloncollie]

Not sure if you've come across this yet: when searching the site you get better results by going to a search engine and typing your search followed by site:fjowners.com

rear radial tire site:fjowners.com

is an example of what you'd enter into the google/bing/duckduckgo search bar.


As far as tires; I loved the Avon Spirit radials but it appears they're not making them anymore.  I couldn't find any at any of the tire vendors including wholesale.  I went with the Shinko 011 front and rear and have about 3k miles on them.  So far no complaints.

[Adamdrives]

Not sure if you've come across this yet: when searching the site you get better results by going to a search engine and typing your search followed by site:fjowners.com

rear radial tire site:fjowners.com

is an example of what you'd enter into the google/bing/duckduckgo search bar.


As far as tires; I loved the Avon Spirit radials but it appears they're not making them anymore.  I couldn't find any at any of the tire vendors including wholesale.  I went with the Shinko 011 front and rear and have about 3k miles on them.  So far no complaints.

Good tip.

I'm looking forward to getting the Shinkos on, they'll take a week to get here from the east coast. The current tires have a date code of 2005 If I had looked a little closer that would have been a dead giveaway the bike had been sitting for some time. I knew it would need tires, so I didn't bother checking.