2008 LS650. 5400 miles. All mods listed in footer/signature.

OK...bike was running ok before but I felt like the stock petcock was causing a sputter now and then so I:

a) got a stock petcock rebuild kit and installed it.
b) cleaned the carb for good measure (it was super clean already) and installed Dave's stainless allen screws.
c) new front brake pads.
d) installed my rear pulley shim.

Now I know "c" and "d" have nothing to do with this, but I am just splanin' it all anyhow.  

Yesterday was the first really good ride I did since the maintenance above and on the 8 mile trip to work it ran top notch. Stopped and fueled up half way and then drove the remaining few miles to work.

On the way home after a few miles in, I felt like the response to my throttle adjustments around 45-55mph were jerky. The closer I got to home I noticed that if I didn't stay in the throttle pretty good at a stop light the engine would cut out. I babied it home and tried to adjust the air/mix with no impact. Switched the petcock to reserve/prime sveral times just to see if maybe the new petcock innards were stiff and needed a little jogging. Prime seemed to make it not choke out as bad, but still not running all that great, especially at idle.

I drained about a cup of fuel from the float bowl drain and it seemed to flow pretty well and clear. Had a few specs of stuff in there but I think it was from me using a cup with some dust in it. Subsequent draining showed a clear, clean cup.

I know I need to pull the fuel line off the carb and test the flow directly and as well do the old petcock test to see if in fact the stock petcock is still failing despite the new innards. I am also going to see if the local small engine shop has a vacuum line to replace the stock one for good measure also.

Anyhow, aside from knowing what I need to look at as noted above, why would the bike run "ok" at speed but really piss out at idle?  If it's not a petcock or fuel flow issue, could it be that some trash snuck past the petcock screen and has jammed up one of the jets?  With my new allen bolts I can and will check and clean the jets again for good measure although they were spotless 20 miles ago when I cleaned the carb.

I know...I know...get the raptor anyway!

stewmills wrote on 11/20/15 at 09:46:07:

Yaahuh... ...

I would do the test where you block off the petcock vacuum line and switch to PRIME....and see if it makes any difference.

If it does.....then the petcock might be working weird as you stated.

Dave: Yes, will do that test.

Todd James: Yes, I thought about that too but the gas came out of the float pretty clean.  However, I think I may drain it so I can check the petcock innards and go get some fresh gas. One of the pumps was bagged so I wonder if it was because the tank was getting low and that particular pump "died" first, hence pulling crap from the bottom?  

Versy: But they were Hello Kitty brake pads from Japan and I put them on with her standing right side up...those Japanese must have printer her picture on there upside down.

Serow and Art Webb:

Stewie! you dog you... got a little pu$$y on your bike... awesome.  

norm92de wrote on 11/20/15 at 13:21:45:


In the photo......looks more like a dog that needs an attitude adjustment!

ok gang. to diagnose things one at a time i first replaced the vacuum line today. took it a minute to warm up and after a few minutes it seems to be running good now. i am probably over anxious since it was acting up befire, but when i rack the throttle open pretty good in neutral and let go it drops back a bit below idle speed then immediately catches up to a good steady idle. prob did this before and is to be expectd on a manual carb. before it would drop off and shut down, so I guess it was a leaky 7 year old vacuum line.  we'll see what the next few rides do but hopefully that was it.

 

thanks dave. i do typically treat her well and am easy on the throttle action. i was just being nore aggressive than usual trying to see if i could get it to choke out like it was before. sounds like im back to normal...well, the bike anyway...