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Discussion Starter #21
Sorry, took a little break over the holidays, now im back. Here are photos of the plugs immediately after the bike dies. Don't know if it means anything, probably not, but trying to mention everything I notice, the front cylinder actually had exhaust smoke coming out when I removed the plug, the rear cylinder did not. The rear cylinder plug was wetter.
 

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rich and fuel soaked. the plugs should be almost white, ethinol burns very clean. when i did pods my plugs were white and i got worried so i backed the pms screws out a little at a time till the plugs showed a little tan. use regular gas 87 or 89. what size jets did you put in. pilot is 17.5 stock and mains are 12.5 and 15.0 the pms screws should be 2 turns out. do you have stock intake and exhaust.
 

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Discussion Starter #23
All jets are new and stock sizes. Pilots are 17.5, mains are 110 and 112.5. I believe I set the PMS screws at 2 1/2 turns out, I can certainly reset them to 2 turns. Everything is stock accept for cobra exhaust pipes.
 

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Yes, very rich. How long did it run? Was choke open when it was running? Definitely close PMS screws down to 2 turns out. Are those BPR7ES (5534) plugs?, that's the stock plug and the correct heat range.
 

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Discussion Starter #25
Yep they are stock plugs,NGK BPR7ES. I will turn the screws to 2 turns out and see what that does. As far as the choke goes, that was with no choke on. It's inside at about 65 degrees so no need to use choke.
 

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All jets are new and stock sizes. Pilots are 17.5, mains are 110 and 112.5. I believe I set the PMS screws at 2 1/2 turns out, I can certainly reset them to 2 turns. Everything is stock accept for cobra exhaust pipes.
with the cobra pipes you can put 115 in both the mains. 2 to 2.5 turns is fine. there should be one shim on the needle. your setup is good there is something else wrong. definitely rich in both carbs. if it was jetted before you got it, it may have dynojet needles.
 

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something else must be off, could the floats be adjusted too high and flooding the jets

or the choke is somehow stuck on

or you are missing a part somewhere in the carbs and its flooding thru the jets.
 

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Discussion Starter #28
I thought of the floats as well and checked them using the tube method out of the service manual, I'm not used to doing it that way, I've always measured from the bowl surface. Anyways, the level was good. As far as something missing, it's certainly a possibility. I don't know what it could be, I've looked at the parts breakdown quite a bit because while rebuilding them, I had a couple of mysterious parts left over. One was a small aluminum piece, which was the main nozzle, which I've never seen them fall out before, and I only had one so I had to order one for the second carb. The other mysteries piece was a copper ring, which I had 2 of those and I guessed that fit around the main nozzle, it was the perfect size. Some parts diagrams didn't even show the main nozzles and it isn't shown in the service manual, but I did finally find it, however, I don't think I ever found the copper rings.

So all that being said, it certainly is possible, something is missing or wrong, I just don't know what it could be.

I also talked to the owner saturday, told him all that was going on so far, he mentioned that when this happened, it seemed like the exhaust sounded louder before this happened, so now im wondering if the exhaust might be plugged?
 

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... The other mysteries piece was a copper ring, which I had 2 of those and I guessed that fit around the main nozzle, it was the perfect size....
My son has a habit of taking things off his car engine, when he doesnt know what they are, and he tells me "that doesnt do anything". Then he complains the car in not running right.

Some engineer spent months designing the part, and GM spent good money to make it and put it on his engine.

If you had parts left over after taking the carbs apart I think that is the likely cause of the flooding. There was another guy here a few months ago who rebuilt his carbs and something like a small cylinder fell out, and he didnt put it back in. His front cylinder was flooding too - he figured out where that part goes and it fixed his bike.

Im assuming the copper rings came out of the carbs, or were they in the rebuild kit? It sounds like a seal or a spacer. If the main jets or TMS screws... are not sealing on one side, the gas will just flood thru.
 

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Discussion Starter #30
Sorry KCW, I didn't clearly explain myself. When I rebuilt the carbs and had them back together U found those parts, once I discovered what they were, I disassembled the carbs again and put them back in. However, that got me to thinking about the copper rings. I did put them in, but I just looked at the parts breakdown again on bikebandit and it shows the nozzle, but not the cipper ring. I think I will take the carbs off again and pull them apart, take pics of the rings and see if anyone can identify them. Maybe they are in the wrong spot. They aren't from the kit, they came out of the carb somewhere. I will do that tonight when I get home.
 

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Discussion Starter #31
So I took the carbs out, bowls off, and removed the main jets. Took a pic with the nozzles still in place, then I removed them and the brass, not copper, rings. The rings only fit one side of the nozzle, if in fact that's where they go. Not even sure what the purpose of them would be in that place. The nozzles are different on each end, and I assumed the concave end would be towards the needle, but that could also be wrong. The nozzles come out very easy, Im wondering if they are suppose to be seated somehow, or if the emulsion tube holds them in place? That's what I got so far though, what do you think?
 

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other than pointing towards the exploded carb diagrams on websites like Bikebandit, I cant help much with this part.

Ive never had to pull a carb apart yet (which is what gave me the confidence to buy my Royal Star, with 4 carbs).
 

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Discussion Starter #33
Yep, that's the problem though, the nozzle is shown in the diagrams, but the brass ring is not, unless it goes in a completely different area of the carb and im just not seeing it. I have actually rebuilt countless number of carbs and this is the first time ever the nozzles have come out. Im sure someone else has seen this, so I'll just have to wait for them to chime in and see what they say.
 

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I recall one of those rings and almost had the same problem. If you look at the exploded carb diagram, there are several rings listed. Specifically, part #19, 5EL–14918–00, is one of those copper rings which goes onto part#20 3G2–1423A–59 ..JET, MAIN (# 42.5).

Those silver nozzles doesn't look familiar to me. I don't see a part like that on the diagram?
 

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Discussion Starter #35
I will look at that, the silver nozzle is #32,

NOZZLE, MAIN 5DM-14141-40-00

The throttle valve needle goes through it into the emulsion tube of the main jet.

One was missing, probably in the bottom of my parts washer somewhere, but they both were out of the carbs. Took me a while to figure out what it was and where it went since I only had one. So I had to order one.
 

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Discussion Starter #36
So I will have to look when I get home to see if that ring, #19, is on the jet. I think it is, but I will look. The only other rings listed are #22 and #44, and it is neither of those and they are both there. Thanks for the tip, we shall see.
 

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Discussion Starter #37
CanadianMohawk, you my friend are a genius!!! That is exactly where those rings went. I don't quite understand the purpose of them, but I don't have to. Carbs are back on the bike and I can now twist the throttle without it dieing. Still have to tune it properly, but that seemed to be the fix. Thanks for all the help, you guys are awesome!!!
 

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I went back and read your first post, and everything up to here.

Originally the owner said he went to fill up the tank, and on the way back the engine backfired, and then it would not run right (bogged when the throttle was twisted).

You cleaned the carbs and the problem remained the same....

After a bunch of other tests and stuff, you found the carbs were not assembled right (in so many words).

There are two possible paths here:

1. The bike sat for a long time, the tank was full of old gas and goop. Owner took the bike and filled the tank up, flushed the goop into the carbs, backfire, wont run... You cleaned the carbs and fixed the original problem but in the process made a mistake putting them back together. The odd thing here is your mis-assembly step resulted in a symptom the same as the gooped up carbs. That seems odd.

2. Owner took the carbs apart, messed them up, put them back together and did not tell you. Maybe the bike sat for a long time and putting new gas in the tank flushed the goop into the carbs, and then he tried to clean them and messed them up. When you took them apart you put them back together the same way that they were. This seems more likely.
 

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CanadianMohawk, you my friend are a genius!!! That is exactly where those rings went. I don't quite understand the purpose of them, but I don't have to. Carbs are back on the bike and I can now twist the throttle without it dieing. Still have to tune it properly, but that seemed to be the fix. Thanks for all the help, you guys are awesome!!!
awesome! Glad I could help! I definitely owed one to this community from getting so much help trying to get my own bike up and running last summer.
 

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Discussion Starter #40
KCW, you are pretty much correct. One thing you have to remember though, I based my initial prognosis off of what he told me the symptoms were. The bike sat for about 6 months to a year, when he told me what it was doing I told him it sounded like dirty carbs and they needed rebuilt. Months later I asked him if he'd gotten around to it and he said "no, but to be honest I feel uncomfortable in my abilities to do it" so I said just bring it on over and I will take care of it. So, I'm not sure if the symptoms were exactly the same but pretty close, however when your talking about carb issues alot of things can cause the same symptoms it seems. So I think the original issue was dirty carbs, and when I pulled them apart there were crystals in the bowls and holes in the jets plugged, I've seen alot worse, but it needed cleaning. The next problem was the shotty workmanship of the mechanic🤬 I'm just glad it's figured out, I'll work on it more tonight to hopefully get it dialed in.
 
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