'90 FJ1200

[FJmonkey]

The 84 to 86 years had a 2nd gear that was a known problem. The shift fork would get bent if a shift was not 100% into 2nd gear before letting the clutch engage during a spirited sprint. It was not as common on the later years 89+. The normal symptom is, it will jump in and out of 2nd gear under hard acceleration, like a rev limiter.  More likely in my opinion, is that 3rd gear was not fully engaged when you let the clutch out. One solution that many have tried and like, is the roller bearing shift kit. When I installed it, the shifting felt easier and positive.  RPM offers this kit for way less than handing your wallet over to a mechanic.

[red]

Hey Red, thanks for the help on methodology as far as narrowing down the circuit that is drawing power. It will help instead of me just poking around with my multimeter. I did find that the heated grips (aftermarket install) were showing 0.15V per side with ignition off. Possibly had been hardwired in somewhere.
While I was riding back to the house, the rear tire locked up momentarily and I started to slalom side-to side. Luckily I wasn't going very fast or around a bend and was able to save it from a crash.  Any guesses as to what happened are very welcome at this point.
-Nick

Nick,

As for the rear wheel lockup, what condition are your chain and sprockets in?  If the chain was trying to fit two barrels into one worn slot (more likely at the front sprocket), that might cause the rear wheel lockup.  If the chain and sprockets are newish, and the chain tension is good, then it was either a wheel bearing (not likely but easy to check for unwanted noises or roughness), or there was a transmission problem (for which I can not advise).  A chain/sprocket problem would have vanished, as soon as you rolled the bike back one inch.  I would track down that problem first, before doing any of the electrical stuff.

For the heated grips, check out a relay-controlled power distribution box.  Done correctly, the relay comes ON when the Ignition does, and the relay contacts send straight battery power to all of the accessories.  The relay draws very little power to switch and hold the switch ON.  So it does not overload the OEM wiring harness.  All of the accessories will be using wires straight through the relay from the battery, so there will be no extra strain on the OEM harness wiring, there.  The best part is, once you turn off the Ignition, you can not be leaving anything else on the bike connected, to drain power.

Good luck.

[sekter1]

Monkey & Red. Thanks for the replies, and valuable knowledge and insights.

My chain is probably in marginal condition at best, and my plan is to replace it along with both sprockets. I'm going to lean towards the chain problem, because it's the cheaper fix, and the chain looks to be looser than normal. The wheel only locked up for a maximum of 2 seconds, and I was still rolling and continued to ride home.  If the chain did load up into the front sprocket incorrectly, I'm thinking I will see some marking on the chain and/or sprocket, and it will ease my worries.

As for the relay-controlled distribution box, I had not thought about that. I guess I could wire it up pretty simply to the heated grips. But it was 104 Fahrenheit yesterday, and I'm not gonna need the grips for a while. I did think that if I just absolutely cannot find the power drain, I'll just install a battery kill switch, similar to what you'd see on the outside of a race car. At least I'd know 100% that the battery won't be connected, for about $25.00.

I'll take pics of the chain and sprockets when I get around to replacing it if I find any indications of damage.

[sekter1]

Found the battery drain.

Apparently being colorblind isn't conducive to correctly identifying dirty old faded wires. Especially a brown vs. red that's covered in dirt and grime. 

When I chopped out the "red plug" going to the generator, I mis-matched the brown and red wires. After switching them back to the correct wiring, no power drain overnight. 12.59V staying in the battery.

Here's a quick fun colorblind test (probably not 100% accurate, but still interesting.) https://colormax.org/color-blind-test/

[sekter1]

I was able to drag myself into the garage this weekend to install a new chain, sprockets, and rear brake pads.

The condition of the old EK chain wasn't great. A few links were kinda tight, but still swiveled with minimal force. I didn't see any evidence where it looks like it got bound up enough to cause the wheel lock incident I had previously described. The front sprocket was in great condition, the rear not so much.

Here are the worst spots on the rear sprocket:



And the only wear i saw on the chain is these vertical lines on the rollers. No major or even minor deformation of any links or rollers. I checked every single link and roller twice.



I've got the new chain riveted on, with the rivets flared ~0.3mm, and then my super high quality MotionPro chain tool crapped out on me (Threads stripped out.) So I'm wondering if this is enough flare on my rivets, as I've read that some people flare them 0.5mm. But they look like they might be over-flared at 0.5mm, decreasing the strength of the rivet.

What chain rivet tool do you use? I'm gonna buy one next paycheck and would like a quality tool that lasts. MotionPro does make a heavier duty chain tool, but I'm wondering if it's worth it.

-Nick

[red]

Nick,

That tooth with the notch across the top is one possible cause of your malfunction.  Lucky that the notch-hit did not snap the chain instantly.  You now owe a favor to a total stranger.    

Those side-worn corners at the tops of the sprocket teeth make it look like the chain has been run too loose, or maybe the front or rear sprockets are not aimed straight at each other.  C-clamp a straight square metal tube, U-channel, or angle iron to the side of the front sprocket (minus the chain) and see where the straightedge is pointed.  It should be pointed at the same side of the rear sprocket.  Do the same for the rear sprocket (minus the chain) and see if the straightedge points at the correct side of the front sprocket. If the front sprocket is set wrong (by the straightedge line), then maybe you have lost or misplaced a shim or two at the rear wheel or front sprocket.  If the rear sprocket is angled wrong, you can simply re-align that sprocket using the chain tensioners at the the rear of the swingarm.  Once the sprockets are correctly aligned, when tensioning the chain, always take an equal number of turns (or half-turns) on the adjusting nuts, on each side of the swingarm.

If the straightedge line from the front sprocket is offset but parallel to the rear sprocket straightedge line, then some shims are missing, or not installed where they should be.  Seek good help, no shame in that, if needed there.  Those old sprockets are now dangerous trash. 

This was a near-miss for you, as disasters go.  Glad that you or the bike were not damaged.   

[sekter1]

Just and update. I'm not dead yet.

Had to slow down on the bike because the truck needed work.

The chain alignment looks okay with some measuring, by way of extruded aluminum stock I had salvaged from work scraps.

But I have gotten a chance to do some work. Cleaned the carbs, found some pretty gunky stuff in one of them, the rest seemed marginally okay.

Also managed to change the oil pan and valve cover gaskets, as they were both slowly leaking.
Just waiting on getting exhaust gaskets from RPM so I can slap that back on and get the carbs synced, and hopefully check that there are no leaks anymore.

I do have one issue I could use help with.

On my bike,the front caliper has blue dots, with what looks like an accompanying change in master cylinder and brake lever. But there's an issue with this. When you turn the handlebars all the way to the left, the front brake lever on the right handlebar is depressed be the gauge cluster plastic housing, and the front brake engages. I really hate this custom feature, and am wondering if anyone has had a similar experience, and the solution you have found.