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Posted
One thing these bikes are sensitive about is spark plugs. Once you have run a good dose of Sea Foam through them and had problems like you have had with the TCI, you need to replace the spark plugs. Unless I missed something, I saw where you replaced just one spark plug.

RandyA

 

Actually two, it's all they had. Going back Monday to get two more.

Posted

So the new TCI has brought new life to this bike. Now I get other people's references to this machine as very fast; the acceleration today caught me by surprise. Wowzer!

 

Now other issues that were masked are apparent. Removed the air cleaner to view the intakes while running and to check the throttle openings. Started it up and noted the following.

 

1) the #1 carb "chuffs" at idle till it warms up to about a quarter needle on the temp gauge. Every couple seconds it gently farts like a backfire, only it's very brief and not strong at all. This is the cylinder that for sure wasn't firing before, so possible stuck ring or valve blow-by?

 

2) the #2 carb has a visible spray of gas from the needle valve into the throat of the carb at idle. The #4 carb has it too, but barely visible. The others don't have it at all. Float height?

 

3) the throttle springs don't pull the throttle completely closed; I have to manually twist the throttle the last little bit. Not much, but enough for a couple hundred rpm. No clue on this one. First bike I've had with a double-cable throttle set-up. Seems like there's lots of room for slop with the plastic twist at the handle bars, the plastic cable cylinder and sliders, and the rod and springs between the four carbs. Not knocking the layout, just alot of moving parts.

 

And of course, leaving town till Tuesday so can't get back to it with whatever suggestions y'all come up with. Soaking the #1 cylinder with Deep Creep tonight. Will look further when I get back home.

Posted (edited)

No comment on 1 & 2

 

As for #3 the tight cable. I experienced a little of that after having my carbs off. What I found was that I had the throttle play adjustment at the carbs just a bit too tight. This is the adjustment between the cables from the throttle and the cables to the carb. There is instructions on page 4-9 in the manual. The spec is 15mm but that took all of the slack out of the carb side. So I loosened it just enough that the cable on the carb side was no longer taut.

 

The adjustment on the twistgrip is just for the amount of freeplay up there.

 

This may and may not fix your #3 problem, but it is an important adjustment none the less.

 

If you do not have a manual, there a link somewhere for it. One of the guys can post it for you.

 

IMG_20140525_110159511.jpg

 

IMG_20141006_082600704.jpg

 

 

So the new TCI has brought new life to this bike. Now I get other people's references to this machine as very fast; the acceleration today caught me by surprise. Wowzer!

 

Now other issues that were masked are apparent. Removed the air cleaner to view the intakes while running and to check the throttle openings. Started it up and noted the following.

 

1) the #1 carb "chuffs" at idle till it warms up to about a quarter needle on the temp gauge. Every couple seconds it gently farts like a backfire, only it's very brief and not strong at all. This is the cylinder that for sure wasn't firing before, so possible stuck ring or valve blow-by?

 

2) the #2 carb has a visible spray of gas from the needle valve into the throat of the carb at idle. The #4 carb has it too, but barely visible. The others don't have it at all. Float height?

 

3) the throttle springs don't pull the throttle completely closed; I have to manually twist the throttle the last little bit. Not much, but enough for a couple hundred rpm. No clue on this one. First bike I've had with a double-cable throttle set-up. Seems like there's lots of room for slop with the plastic twist at the handle bars, the plastic cable cylinder and sliders, and the rod and springs between the four carbs. Not knocking the layout, just alot of moving parts.

 

And of course, leaving town till Tuesday so can't get back to it with whatever suggestions y'all come up with. Soaking the #1 cylinder with Deep Creep tonight. Will look further when I get back home.

Edited by yamagrl
Posted

I ended up doing the same thing. I guess the 30 year-old cables are stretched, and I took too much slack out, so loosened till everything worked without binding. And my slider doesn't look like yours, it's just a rectangular block about 4" long. Also I do have a manual.

 

I've run out of time as far as troubleshooting the carbs. An initial check of the #2 carb float level has it in the normal range, so I don't think it's flooding. I put Seafoam in the tank and ran the engine till the fan came on, now it's soaking. Won't be able to get back to it till November now. Sure would like to get out and run it hard before we leave town for three weeks though. Guess it will have to wait.

Posted

You didn't mention if you aired up the tires....changed the fuel filter...at least I didn't catch it if you did...or even changed the oil.....Just pointing out other things to be considered...

Posted
You didn't mention if you aired up the tires....changed the fuel filter...at least I didn't catch it if you did...or even changed the oil.....Just pointing out other things to be considered...

 

This bike sat under a leaky shed for 6 years and had to be pushed onto a trailer to be hauled to my house. So I had to go through everything. Got a new tire up front, new oil and filter, new fuel filter, new air filter. Hell, the tank is a good unrusted ebay unit as the other one had a layer of rust and varnish in the bottom. New slide diaphragms, new gaskets and seals in all carbs, cleaned a lot of crud and varnish out of the carbs, blew out all passages. Replaced the exhaust collector, which had rusted through and had a mouse nest in it. On and on the list goes, not much original left on the bike at this point. Either a labor of love, or stupidity, only time will tell.

  • 4 weeks later...
Posted

Upon further review..

Been working with the new brain box and trying to iron out a new set of probs. Before going too deep I'll just remind all that this bike is new to me as of February so it's still pretty much unknown. I've only put about 300 miles on it since bringing it back to life.

 

It runs like a banshee being chased by a woolybooger :confused24: so happy there. But on startup and idle it chuffs on the right side only. At 2000 rpm there's a pretty good popping from the right pipe. Pulled each plug wire one at a time and it still popped. Pulled both boots and the popping went away and it ran like it did before the new TCI.

 

So my issues are with #3 and 4 cylinders. Checked float levels and they were close eyeballing it. Checked for leaks, both air and fuel, found none. As the engine got warmer idle increased from intermittently having to give it throttle to keep it running, to a mostly steady 1500 rpm.

 

As the temp gauge approached the top of the green, just before the fan kicked on, blue smoke started coming from the right side exhaust. That made me stop and come get on the forums to you folks. I'm wondering about valve blow-by, stuck rings, burnt pistons, broke rings, all the nightmare stuff that I can't fool with at the mo as we're between houses. I'm gonna pull both sparklers once it cools a bit to see if I can narrow down which cylinder it is, but it may be both since it pops with either plug wire off but not both.

 

So what's y'all's thoughts?

Screen Shot 2014-11-16 at 1.21.38 PM.jpg

Posted

Buy some Marvel Mystery Oil and put some in the crankcase. Run the bike for a bit to circulate the oil. Then I'd pull the two oily plugs and put some Marvel Mystery Oil in those cylinders and let it soak while you're moving. Maybe this will free up stuck rings. I also agree that new plugs are important to these bikes, especially 83's because the spark is a little weaker on them. I'd probably clean the old plugs up as best possible, and then verify that they spark before re-installing them. Then I'd run the bike for a bit to burn off the Marvel Mystery Oil. Then I'd put in new plugs.

Posted

Thanks, #3 is a new plug. I'll replace the other two old ones and try the Marvel. We used to use it in fish-spotting aircraft engines and fuel tanks all the time, everybody swore by the stuff.

Posted (edited)

Anybody know if the carb floats are solid or hollow? I think they're solid. Mine are looking their age so I might replace them if I can find them.

Also, my parts place says 83-85 is one part #, 86-93 is another. Anyone know if the floats are the same?

Edited by flyday58
Posted

The floats are solid, though buoyant. There have been some reports that the float can become 'fuel-logged'. Some have attempted to dry them thoroughly and then coat with a fuel resistant sealer. Mixed results.

Your parts guy is correct about the 1983-1985 floats being different from 1986-1993, but I don't know the difference. It does seem odd that there would be a difference.

Posted

yes...that's intake honk we hear with stock pipes. I have seen rpm well past redline a few times in the past 25 years with mine. But to back track. Your resistance on OEM caps is supposed to be 10k +/- 10% NOT 5k........... 5k is the spark plug or NGK caps resistance. With oem caps they do come apart. BUT the resistor should not be sanded. Which will increase the resistance. Odd but true..... I have also experienced the same thing with the resistor caps. JUST DON'T sand the resistors' ends

Posted

I'm gonna close this one out and say problem solved. The root of the issues was definitely the water-logged TCI. With the Ignitech unit installed the other problems were unmasked. Had one decel diaphragm that was turned to hard plastic, and the idle air ports were all clogged, along with 2 or three others I missed. Runs great, extremely quick, almost threw me off the first time I rapped the throttle open.

 

Thanks for everyone's help on this. Onward and upward.

Posted

Let us know what your mileage is on the 2nd tank. If you are like me, the first tank will be low MPG due to the wrist/throttle issue that develops once we get a taste of the power and thrust of a good running 1st Gen. I just corrected my carb issues a month ago and it almost threw me off when I cranked it open, so I know just what you mean.

  • 6 months later...
Posted

Not reopening this thread, just saw I didn't reply. Mileage continuously improved to 35, then 38, then 40 mpg. Bike is now parked in my new garage 1200 miles west and 9000 feet above our temp quartes in Ole Miss. Hopefully it doesn't have to sit much longer before we move in permanently or I'll be yankin carbs or going thru gallons of Sea Foam again!

Posted

i am getting on this late. But the caps should be 10k +/- 1k. The spark plugs are should be approx. 5k. The resistors in the caps should never be cleaned with sand paper. as the shorter they are the higher the resistance. It changes quickly.

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