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My 84 is getting harder to start. I thought it was the cold, then the hi-test gas. I run regular in it in the cold months for it's lower flash point. Now regardless of the temp or gas it takes a while to get it started. I think the ignition module (original so far as I know) is on it's way to the trash can. Opinions please!

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Maybe the choke (enrichment) linkage is not set correctly to move the enrichment plunger all the way out. The plunger is moved by a metal linkage that is activated by a cable clamped to the carb frame. The clamp provides the means to move the cable for the adjustment.

-Pete, in Tacoma WA USA

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In addition to checking for full enrichener opening by the cable adjustment Pete mentions, also check that all four enricheners are fully opening. Sometimes one or more of the enricheners are maladjusted. The individual enricheners may not all be fully opening when the 'choke' lever is fully rotated to 'choke'. Check that each enrichener actuating lever is adjusted correctly. The enrichener actuating levers are clamped to the common actuator bar with set screws. Check each for correct travel adjustment and for all the set screws to be secure.

Enrichener adjustment screw (Custom).jpg

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Do you have the 4 brush starter?

My 84 was rough to initially start as well & then of course, when it was hot it would be a pain.

Once I replaced the starter to a Gen 2 starter & got a new battery from Skydoc, my starting woes ended.

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Is your battery real good. If not I'd try that first. If the voltage is a bit low these beasts will turn over but not start. Try a set of jumpers from the car ( do not run the engine on the car) and see if it doesn't start better.

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Battery: GREAT

Choke: Story: One night I used the choke, I got so much gas in the the mufflers they went BOOM! I thought the cops were going to come investigate because it sounded like a weapons discharge.

Plugs: Less than 4k miles, of course that doesn't mean they aren't fouled from choking. I have a new set on hand.

It has been stated here on the forum that 1st Gens don't need much choke, I have found that to be true, it starts way easier with NO choke or VERY little choke.

Starter: 4 brush model. I replaced all the starter/battery related wiring with No. 4 stranded wire, soldered the terminals to the wire(s) too. The starter spins real nice, no voltage or amp issues there.

I wonder if the Ignition isn't going bad....sure would be a good reason to get (authorization from she who must be obeyed (swmbo) to buy) that electronic one offered here on the site....(looks around in a sneaky way) It IS 30 years old.....

When cold it takes 4 to 7 tries before it catches enough to stay running, then the RPMs increase as the oil gets flowing. I have LUCAS 10W30 M/C oil in it.

When it's warm it re-starts just fine.

I am pretty sure all the choke parts move and move equally, well i know the MOVE...I have never fooled with them except to get the crud off the out side of all the carbs,,,Pete has seen the carbs (when he kindly sync'ed them for me last summer) and I would be flabbergasted if he didn't notice something like the enrichers being out of whack but I'm sure it's possible he didn't but I have my doubts about that. Pete KNOWS these carbs; trust me.

Edited by dna9656
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...When cold it takes 4 to 7 tries before it catches enough to stay running, then the RPS increase as the oil gets flowing.

 

Doug, that's normal for me. I usually cycle the fuel pump 3 times by turning the emergency switch on & off with the ignition on until it doesn't click anymore.

But DEAD COLD especially in winter, it takes several tries before she will stay running.

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It's never done this before; even before I replaced (only God knows how old that thing was) the fuel filter. I'm leaning towards the plugs being fouled out or the Ignition is going south....I'm still waiting on more feedback here.

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With 4000 miles on the plugs, they should be fine, but new plugs will definitely help. Your engine filling up with unburned gas when you use full choke points to weak spark. My 83 has had this problem since it was new. One way I found to help was to use about 1/2 choke, and then started to crank and when I heard 'life' (a cylinder firing) I blip the throttle. The bike usually starts great. There have been times that I've had a terrible time getting it started though. If I think that it's become flooded, I turn off the choke, and crank it while I roll the throttle open and closed. Sometimes this makes it start. If not, I turn on about 1/2 choke and start all over. If it's about 40 degrees, I use full choke.

 

Here's something else to check......Seeing that a new battery and new plugs help so much, making the spark stronger will do wonders.

Venturous Randy found something that would help this problem. He found that on his 83 that when he was cranking it over, the voltage going to the TCI went way down and the spark was weak. He added a relay that used the red TCI lead for the relay's coil and wired it so that the relay contacts switched a better source of voltage to the TCI. Now, I haven't done this mod to my 83 because my brother is using it, and he never rides in cooler weather. Take a DC voltmeter and if your TCI is in the stock position, use a pin to puncture the TCI red wire's insulation. Connect the red meter lead to this pin, and the black meter lead to ground. Crank the engine over and read the voltage. Then move the meter's red lead to the battery and repeat the test. The difference between the two readings is the voltage drop in the bike's wiring harness. Now Yamaha changed a lot of the wiring in both the 84's and 85's compared to the 83's. You probably will have to pull the battery and battery box to get to this, but to test it just set the battery on the frame brace that holds the battery box. Mk II bikes are different yet, and they don't seem to have this problem. My 89 starts great, even with worn spark plugs and a battery so weak that it'll hardly crank the bike over.

 

I searched for Randy's message, but it didn't jump out and grab me. He's changed his handle though and I may be looking for the wrong one. Maybe he'll jump in here and let you know exactly how he did this. If not, I'll search more or write a detailed message that tells you how to do this step if it's necessary. Something you could do to tell if this will help your bike.....Using the pin in the TCI red wire, connect a jumper to it. Be careful that it doesn't touch ground or you'll blow a fuse. Turn the key ON and connect the other end of the jumper to your batteries positive terminal. Then see how well your bike starts.

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