Author |
Message |
Scdobber
| Posted on Friday, April 23, 2010 - 03:22 pm: |
|
This Buell is really getting on my nerves,seems like every time I ride there is a carb related issue.A few weeks ago I installed new James blue intake seals as well as new 10R12 plugs,at the time the weather was cool mid 50's bike run perfect,today the temp is in the 80's and it's hesitating on off idle revs or if I let it idle for say 30 seconds at a stop light and rev it it pops through the airbox,not sure if it's getting too much fuel or not enough.I double checked the intake with propane for leaks and found none.It did this a while back on a warmer day.Any tips? I'm running a stock 195 main, 45 slow and 2.75 turns out on the mixture,no shims yet. |
Jramsey
| Posted on Friday, April 23, 2010 - 03:33 pm: |
|
Its lean if coughing back thru the intake. |
Scdobber
| Posted on Friday, April 23, 2010 - 05:10 pm: |
|
Why warmer weather than cooler? I always thought 4 strokes run leaner in cooler weather and richer in hot,I may be wrong on that.I'll toy with the mixture some and see what happens |
Jim2
| Posted on Friday, April 23, 2010 - 05:43 pm: |
|
Try turning your idle mixture in .75 to 1.0 turn and see if it continues. That should answer your question, "is it too rich, or too lean". You can try this when it's cold and not running so you don't need special tool and don't burn yourself. You can easily return it back to the same place again. Other than that your main jet shouldn't be a factor off idle and your slow jet is already what it should be. If that test answers your question you can then dial it in using a more proper method. |
Scdobber
| Posted on Friday, April 23, 2010 - 08:11 pm: |
|
Well,I went extreme and went 3.5 out and the issue remained,pulled the plugs and they were black,so I went back in to seated and out to 1.5 turns,that cleared the plugs up and seemed to help but the temps were also dropping so I will not be able to really tell till the next warm day |
Guell
| Posted on Saturday, April 24, 2010 - 09:17 am: |
|
I would shim the needle, I run about the same with a 200, 45, 2.75 turns out and a shimmed needle and it runs awesome |
Scdobber
| Posted on Saturday, April 24, 2010 - 11:03 am: |
|
How much shim would you run on a stock bike,I tried .050 which was too much? |
Scdobber
| Posted on Saturday, May 01, 2010 - 10:53 am: |
|
Well,I'm still having off idle hesitation when the weather is hot,looking at the plugs it is running rich.I am running the mixture 1 turn out with the 45 slow jet.I'm wondering if I need to go back to the 42 and work with the mixture setting.At cruising speed and WOT the bike runs fine.I think the vacuum leak at the intake was causing issues with the 42 jet causing it to lean out. |
Ratbuell
| Posted on Saturday, May 01, 2010 - 11:04 am: |
|
45 seems fat for a stock exhaust (you didn't say), or even for a mild aftermarket. I run a 42 in my S2 (stock 2" header/Buell race muffler), and did on my S1W with V&H slip-on...but the switch to the Buell race exhaust (header and muffler) made it happier with a 45. Both run 195 mains. Her M2L, full-stock, is happy with 42/190. |
Cyclonecharlie
| Posted on Saturday, May 01, 2010 - 01:26 pm: |
|
One thing that hasn't been mentioned, you could possibly be trying to run your idle too low. This isn't a sportster or Harley, it likes a higher idle(plus helps keep the oil press.up)I set mine at 1K-1200. If idle is too low, the bike will cough. |
Buellistic
| Posted on Saturday, May 01, 2010 - 01:51 pm: |
|
Cyclonecharlie, if "i" was up there it would be a nice ride to Mullins just to fix Scdobber's bike ... |
Cyclonecharlie
| Posted on Saturday, May 01, 2010 - 02:40 pm: |
|
LaFayette, If you were up here........we might just do that. |
Bluzm2
| Posted on Saturday, May 01, 2010 - 03:35 pm: |
|
45 is fine for the pilot. 42 is too small, way lean.. 2 1/2 turns is usually the starting point. |
Scdobber
| Posted on Monday, May 03, 2010 - 01:06 am: |
|
LaFayette,I wish you and Charlie were right down the street.When I first got the bike it had bad hiccups/surging at low speeds with stock jetting and a capped mixture screw.I went with the 45 slow jet and set the mixture at 2.5 turns which did help the surging but for some reason the bike lost power throughout the rpm band so I went back to the 42 jet and left the mixture at 2.5,it felt a tad better but after a few rides of dealing with the low speed cough went back to the 45 and with your help found a vacuum leak with propane which WD-40 failed to detect after going through almost a whole can.After replacing the seals with the James Blues it fixed the vacuum leak.The plugs went from snow white to a nice eggshell color but as the weather began getting hotter I noticed the bike would hesitate at off idle revs and after setting at a long stoplight it would hesitate more and pop,I feel like it is more like a slight bog from the shot of fuel from the accelerator pump,I thought lean but after looking at the plugs they were black,I turned the mixture out to 1.5 turns and it helped and the plugs cleared up some but still had light hesitation.I am now at 1 turn out running the 45,so far it seems ok,why richer when hot I have no idea?? I am past the issue of surging and bucking in town with no coughing so that's positive but it's still not perfect.The previous owner stated it always run fine,no coughing or surging until one day it started out the blue at 1100 miles on the clock but figured it was from lack of riding which now I see it was failed intake seals.I thought about trying the 42 slow jet again and work with the mixture seeing the vacuum leak has been eliminated but I'll try it like it is for a while.I can say I've got pretty quick at pulling the carb |
|