Idle rises as bike warms up among other issues...

danisawesome

danisawesome

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Hello everyone! I'm running into a few snags as I'm attempting to figure out my fueling settings. First off, the bike has pods and straight pipes, so jetting has been changed to 142.5 mains, 45 pilots, and a washer on each needle to raise it. Mixture screws are at about 2 to 1.5 screws out.

Problems I have been combating are difficulty starting when cold, which takes around 10 kicks with either full or half-choke, accompanied by having to raise the idle speed to get the bike to start and then adjusting it back down as I ride and it warms up. Also, since shimming the needle I have experienced a bit of hesitation and possibly break-up (not sure if that is the correct term for it) at about 1/4 throttle at 3-4.5k rpms. I started with 2 shims on the needles and the stuttering was worse, but it felt amazing as I applied more throttle and just flew into the upper rpms.

Any advice from you jetting/carb gurus? I'm kind of stuck and not sure what the next step is. I'm thinking it all must be related to one main issue, but I'm not positive. Carbs are for sure squeaky clean (ultrasonic and dipped recently with all new seals (except butterfly), float needles, jets, etc.)
 
Turn your mix screw out to 3 and put the needle in the stock position. What do the plugs look like?
 
Alright, mixture screw is 3 turns out and needles back to stock and the idle is much smoother, the bike starts in about 3-4 kicks, and the breakup is gone. The idle is still a little unpredictable, but I'm wondering if it's the butterfly shaft seals as I dipped the carbs but never replaced them. I have them sitting in the garage, but it just seems like a pain in the ass to do. I also ordered new exhaust gaskets as they are the original ones and probably a little busted.

I will have to check plugs in a little bit as I took it out for a test run and it was the most fun I've had on the bike in a while! Before though the plugs were reading pretty rich with just a tinge of tan coming through.

Thanks a ton, Chris! I've been trying all sorts of settings and just couldn't find the right combination. I'm wondering if I need a larger main, but I will wait until I pull the plugs to see if it's necessary.
 
Left side plug looks to be rich with a slight tinge of tan and the right side looks like it's really close, maybe just a tad rich. It's supposed to rain all week, but hopefully I will be able to get out and do some fine-tuning if we get some sun breaks.
 
Ok, bringing my thread back as I'm still trying to figure out why I can't get things perfect. Everytime I pull the plugs they are black all over with one side showing a little tan coming through and a little on the ground strap. Is this normal? I just took these out in favor of new plugs and the pictures are from after a ride around town. Bike starts in 1 or 2 kicks, idle is a little bouncy, and it acts just the slightest rich in very low RPMs. Other than that the bike feels really good, so I don't want to make any drastic adjustments if I don't need to.

The dark side:
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The light side:
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Top:
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Poor idle seems to be common theme w/ these bikes. When you say bouncy, do you mean rough like its slow or sounds as though it wants to stall? Or more like it keeps gaining rpm and you have to keep adjusting it down?
 
I wonder if if my pods are obstructing my airjets also.I can get it to run almostperfect till I hook up the vacume line to the petcock or plug it off.
 
Bizzy13 said:
Carbs clean? Are you running pods that obstruct your air jets?
Click to expand...

Carbs are ultrasonic clean and have new everything in them and I used the stock intake tube so my pods don't obstruct the air jets. Just went out for a short ride today and it was having a tough time staying started when kicking it after stopping at the auto parts store. I had to give it a bit of throttle to wake it up and then it was fine again. I might just go a size smaller on my pilot jets to see if that cures the problem.

Scorpio1963 said:
I wonder if if my pods are obstructing my airjets also.I can get it to run almostperfect till I hook up the vacume line to the petcock or plug it off.
Click to expand...

I have those cheapy Emgos on mine and they have a rubber lip on the inside that will cause problems, which is why I use the stock intake tube so they aren't mounted right on the carb. You would think that your bike would hardly run without the vacuum hooked up as it would be a pretty big vacuum leak and run very lean.
 
I have the same pods they are gettting trashed soon as Im getting something much better.I used part of my airtube and made an extension so that the pods are about an inch away from opening of the carbs.As soon as I hook up the vacume line the throttle speed will just take of to about 4-5ks Didnt ever have this problem before.I noticed the problem with the emgos is they have no filter inside or outside of them.They literaly just suck way to much air.Im gettting a set of oval pods that are the K and N knockoffs.
 
If you use pods you should use proper filter oil on them. They will work much better:thumbsup:
 
I'm using oval MikesXS pods. Seem to be working nice. No oil though, maybe Ill try it but at the same time, Im getting nice tan plugs, hate to fix what isn't broken.
 
As far as Im concerned unless emgo starts going higher quality Im never buying their junk again.The pods they sell do nothing to protect the carbs from dirt or dust getting sucked into them.Yeah I know one particular member here told me so.For now I have filter material wrapped around the inside of them.
 
So, moving down a size on the pilot jets and readjusting the floats did the trick. No more black plugs; now I just need to fine tune via the mixture screws.

@Scorpio, were there any changes at all to the bike before it started revving to 4-5k with everything hooked up? I'm assuming you checked, but is your idle adjustment screw set properly? It sounds like something was compensating for the vacuum not being hooked up and now when it's hooked up it is functioning properly again and revs really high.
 

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