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Another scary noise thread
- Thread starter Devin
- Start date
I've still gotta drop the bowls and see whats in there. I'd assume its stock but you never know. I wasn't able to do much with it the last couple days but I did take it for a good ride and it's running pretty good. It seems to lean out a bit when it's really up to temp. The airboxes are stock as they should be lol. Hopefully I can take the carbs apart again soon and give you guys some specs.
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Likely NOT lean when warm, otherwise it would be very lean when cold. More likely it is running rich when warm.
Ok, so I pulled the carbs and the mains are stock at 132.5. So I should go and get a set of 131s or 130s? When its hot midrange has a stumble and top end is weak. So with a set of smaller mains where should I set my needle?
Start with the top end, above 8K RPM and full throttle, to get the main jets correct. If 132.5's are weak, try 130's (the jets come in 2.5 increments). Ignore how the bike runs at any other RPM or throttle setting! Pick the larger jets that run the strongest if you find yourself wishing for jets "in between". It is easier to remove carbon than to replace pistons. Once you have the main jets sorted, you can try the mid range and play with needle height and then float levels.
This is a process that takes time, patience and dedication. That is why so few ever get it right.
This is a process that takes time, patience and dedication. That is why so few ever get it right.
So I'm getting my jets tomorrow. I'll grab a set of 130s and 127.5s. I gave the carbs another really good cleaning. I verified all the jetting is stock but the floats were set waaay off. They were around 23-24mm so I set them back on the rich side of factory spec.
After doing some research on float height I threw the stock mains back on and I'm gonna see how it runs with the super clean carbs and correct floats. From what I read that alone should take quite a bit of richness away.
Tried her out this morning. The floats are going to go back to where I found them. The bike wouldn't even rev without choke. Which is odd because I have them well within spec at 1.156" so why doesn't it like that? Spec according to the book in the stickies is 32mm (1.259")
This.
A quick search of this site said the same thing. Just set them to 26mm and took her for a 3 mile spin, BIG difference. Granted it wasn't toatally warmed up but I wanted to show you guys the plugs first. These were after a mile long 4.5k cruise in 6th. You can definitely see the line of carbon on the line of carbon on the insulator.Attachments
The plugs still look rich, but not too bad.
When checking the float levels, now that you have them close by measuring their height, check the actual fuel level in the float bowls with the bike running. A length of clear tubing connected to the bowl drain and a level spot to park the bike is all that is needed.
When checking the float levels, now that you have them close by measuring their height, check the actual fuel level in the float bowls with the bike running. A length of clear tubing connected to the bowl drain and a level spot to park the bike is all that is needed.
Well I did and I got... interesting results. After 4 or 5 miles I started doing my plug chops. Low rpm cruise and 5k chops looked just like the previous pics, a tad rich but I'm ok with that. Then I started the WOT tests. I've been testing on a dirt road (bike isn't registered yet) so obviously 4th gear at 8k would be suicidal. So I was revving her up through second gear and I held it at 8k in second for about 5 seconds and my dumb@ss pulled the clutch a second before I let off the throttle and I watched the tach hit 10k before I killed it and pulled the plugs. I don't think it hurt anything but I was wondering what the redline is on these and how forgiving are they? But anyway, after that I said screw it I'm just gonna go down to a 2 lane backroad and do this right. I got 2 WOT chops one in second and one in 4th. Both are wierd. The right cyl is almost a pinkish light tan like the other plug chops. So I'm good with that. But the left, is sooty and yellow. Wtf? And when I rode a mile back to the house the last thing I did was another 5k chop and the left cyl started to get normal color back.
Pic 1: wot 4th right
Pic 2: wot 4th left
Pic 3: wot 4th left
Pic 4: 5k left when I got home
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Look inside the plug, at the base of the ceramic insulator. Use a magnifying glass and the sunlight, or a bright light. That is where you read the mixture on an extended reach spark plug.
90% of your riding is going to be at 4-5k rpm's. If your bike idles well and runs good under a normal rpm range I would leave it be. If your going to be racing the bike or spend hours on the interstate at 90 mph don't worry about them. You will spend too much time chasing a "perfect" tune. If you want that find a dyno to test the bike on or put an o2 censor in you exhaust.
I'm seriously thinking I'm gonna leave it be. I'm just worried about the massive difference between the two carbs at high rpm.
Ok guys, bikes running good so far I've put 100 miles on her cruising backroads. But the ticking that made me start this thread never REALLY went away. I realized the helmet I was wearing muffled it out. Amd I was going through partzilla today and I saw that there are a couple of parts in the oil filter cover that I'm missing. Parts 15 and 16 weren't in the assembly when I changed the filter. Could this be causing weak oil pressure? Meaning increased noise? Regardless the parts are on order but I wondered...
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I believe I've figured out whats making noise. The valves are slightly dished where they contact the tappets. So the adjustment is always loose. What's the correct fix here? I've read just to bs the adjustment a bit but I don't like that method very much.