08 stumbling and not moving hard

[scorch]

So lately in the last few weeks my bike when its cold its fine. Rides well, tons of power and all of that.

After it warms up, it starts to stumble. So if i give it throttle i hear the bike, but the bike is not moving. And its gurgling a bit, as if its running out of gas.

I thought at first i got bad gas, but now im on my 3rd gas tank and still the same.

Feels like a carb issue. Because if iopen up the throttle wide it hesitates a bit.

Also when its warm, at idle it dies if i dont have some throttle on. ANd if i put it at 2k rpms and keep it stable it comes down by itself.

Anyone know any ideas of what it might be. 87k miles on the bike.

Thanks

[Ghostt]

What other information can you provide, did the bike sit? Daily rider? Did you make any changes before? Fuel filter? Etc..... You get the point

[scorch]

it sat a few days. I have 2 other bikes that i ride daily. I ride this one at least 2 times per week.

I didnt make any changes to the bike at all. Just ride it. Its had a recent oil and filter change. The oil level is fine. Checked the air filter and its clean.

But basically i do ride it often, often enough it shouldnt gunk up the carbs that easily if i leave it for a few days right?

[Ghostt]

87k is a lot of duty cycles for the moving parts inside those carbs

Yes, the unstable idle and inability to hold steady RPM at partial throttle indicate some problem in fuel metering.

I'd suggest to fully service the carbs (replace the float valves, set the fuel levels) , spark plugs, purge the fuel (water congeals at the bottom points of a tank, btw) , check all filters, etc etc.

Also have the other recommend services been performed.

[scorch]

The carbs are actually new from another bike. So they are the newest things in the bike lol. Ill have to pull the carbs apart and look at them. Not sure if the float valves are off. Might the needles be gunked up?

[Ghostt]

Check the slides too, and are you running a fuel filter? I would as long as you have them out, give them a good and through going over and clean, etc.....

What about other services done? Plugs? Plugs caps? Etc.....

[scorch]

not running a fuel filter. Just the one that is in the hose that comes with the bike.

The sparkplugs are fairly new, but i havent checked them. Ill have to do that first before i pul the carbs. But since i have it off, might as well check it.

Im going to tackle this tommorow. Thanks for the suggestions

[Ghostt]

Just remember to take your time and be methodical.

[scorch]

She is stumbling. So im taking her apart finally. anyone can read these plugs? They seem ok to me, just a little dirty.

When i pulled into my garage the bike smelled of gas.

[scorch]

btw, i had the gas on prime instead on the vertical position. I've run it like this for quite some time, would this effect it?

[scorch]

looked a bit more carefully and i think i might have found the source of the problem. There is a small crack in the airbox that goes from the carb to the box. I had some silicone there but it was flaking out. Im not entirely sure it is it.

But when i sparyed starter fluid when she was idling she wasw spike only in the section.

Im going to get some sealant and hopefuy close that very small crack off.

[scorch]

Alright, so it ws not the airbox. I rode the bike today and it displayed the sam symtoms. Funny is that when its cold with less than 5 iles it pulls really hard as normal. But after warm up, it displays the stuttering and lack of power.

I need to see if its still a vaccum leak anywhere, i didnt pull off the carb or the air box. So ill have to do that .

[jkv45]

Originally Posted by scorch

Alright, so it ws not the airbox. I rode the bike today and it displayed the sam symtoms. Funny is that when its cold with less than 5 iles it pulls really hard as normal. But after warm up, it displays the stuttering and lack of power.

I need to see if its still a vaccum leak anywhere, i didnt pull off the carb or the air box. So ill have to do that .

That sounds like it's too rich for whatever reason.

Pull the plugs and see what they look like to confirm.

[scorch]

The plugs look pretty good

[scorch]

could a weak battery be the culprit here? my battery this summer actually reverse polarity. When I got back from vacation it was on the battery tender and when I went to started it when I want but when I reversed it and the cables it worked.

[cadd]

Have you tried spraying starter fluid or carb cleaner on the boots of the carbs (carb to motor and carb to airbox)? Any reaction with idle speed?

I'm really interested to see what it is. It's just weird that this happens only when the bike is warm.

[scorch]

yes and sprayed starter fluid in the carb boots. The first time I sprayed them there was a little response. I filled a hairline crack width sealant. Now there is no fluctuation in the idle. There seems to be a small gap in test car boot but spraying starter fluid around does nothing. So now I'm not sure if its a vacuum leak. My air filter seems clean, but I've never replaced it. I have high miles on this bike so it could be the air filter?

[scorch]

my trying some seafoam too. Maybe you're running it through the carb my dick trick. I'll let you guys know

[jkv45]

Originally Posted by scorch

yes and sprayed starter fluid in the carb boots. The first time I sprayed them there was a little response. I filled a hairline crack width sealant. Now there is no fluctuation in the idle. There seems to be a small gap in test car boot but spraying starter fluid around does nothing. So now I'm not sure if its a vacuum leak. My air filter seems clean, but I've never replaced it. I have high miles on this bike so it could be the air filter?

Could be. Take the filter out and go for a ride. It would make sense.

Run some Chevron Techron Concentrate fuel system cleaner at 1oz per gal with your next tank. Use 87 octane.

Plugs don't look bad. Overall not black enough to be overly rich during most riding.

A bad battery will cause odd running problems. Check that it stays at 12.7V after leaving it set for a couple of hours (after a ride).

[Ghostt]

Sounds like a good time to upgrade to a K&N air filter to me, I'd personally change the plugs, after all your half way there anyway.

[cadd]

Is there a strong gasoline smell in the airbox when you inspected the air filter? I know you mentioned that you smelled a strong gasoline odor when you pulled the bike in the garage.

[scorch]

[scorch]

removed the carbs. there is a bit of plastic hose in the middle in that pic that is cracked.WHen i bought the this carb, it was broken and i still put it in, so im wondering if that is the reason? it didnt do it and ive ridden with it for several thousand miles.

[Finesse]

'tons of power'???
clearly something is indeed very wrong.




sorry, I had to........

[Enrgkid]

Sounds like a vacuum issue had this a few months back was a spider stuck in my vacuum and this was the cause of the issue

[csmith12]

Originally Posted by Enrgkid

Sounds like a vacuum issue had this a few months back was a spider stuck in my vacuum and this was the cause of the issue

[crazymadbastard]

when where the valve clearances checked last?

[Linkin]

Here is my assessment:

Your plugs don't look the same. As if one cyl is running lean and one is rich. Bogging down could be too lean on one cyl or too rich on the other. Or both. Maybe the mixture is wrong?

I would bench the carbs and have them synced, adjust the mixtures, etc. Run the bike for a bit and check the plugs again

[Ghostt]

Originally Posted by Linkin

Here is my assessment:

Your plugs don't look the same. As if one cyl is running lean and one is rich. Bogging down could be too lean on one cyl or too rich on the other. Or both. Maybe the mixture is wrong?

I would bench the carbs and have them synced, adjust the mixtures, etc. Run the bike for a bit and check the plugs again

Also if one plug looks lean I would seriously look at those connections and check for vacuum leaks.

Bench check those puppies for sure, but your problem is NOT carburetor synchronization, unless something really has gone sideways.