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jetting carb help

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Been dialing in the jetting on my 500.  The bike feels good pretty much everywhere except at idle and off idle to about 1/8th throttle.

Here are the details.  39mm pwk,  Rad valve, 162main, 40 pilot, DGN 3rd,  #6 slide

The symptoms

The bike starts no problem, it will idle in neutral no problem but i think it sounds rich, it doesn't idle very smooth.  Turning the air screw in will get the bike to stall out, turning it out further past 2 turns doesn't seem to change much.

If i turn the idle way in (raise the slide) i can get the bike to idle a little faster but it makes off idle - 1/4 throttle worse response.

While bike is idling in neutral if i put on the choke it stalls the bike.

Unless i have the idle screw almost all the way in so the idle is higher, the bike will not idle while in gear with the clutch pulled in at a stand still.  It must put just enough load on the engine that it stalls it out.   <--- this is my main problem.  I need the bike to be able to come to a stand still with the clutch in and not stall.  The type of riding i typically do involves lots of technical riding in gnarly rocks.  If it wasn't for this it probably wouldn't bother me for normal ripping around.  

my thoughts.

I'm rich at idle, need to either go down on pilot, go to a #7 slide, or my floats are too high, or a combination of those.

Does this make sense based on the symptoms?  Makes sense to me.

Anyone have any tricks for rouble shooting the floats, slide or pilot jet? 

Ill futz around with the bike tomorrow, hopefully i can figure something out and hopefully one of the first 2 or so things i try does the trick  

Edited by subxero

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messed around a bit today experimenting.

First thing, i thought i had the Sudco DGN needle in which is recommended by a lot of 500 riders, but it was actually the DGH.  Couldn't remember why i had the DGH and not the DGN in so i swapped them, the DGN is leaner on the straight.  It was way lean, had to bump the pilot up to a 52, it idled well but couldn't transition at all off idle onto the throttle, no matter what else i did. That's when i remembered why i had the DGH in there.   Then i started wondering if what i was feeling was actually a rich feeling and not a lean feeling, it's hard to tell at that small of a throttle opening and range?  

Either way, it will be more normal temps tomorrow, a bit chilly today.  I will mess with it more, will be a much nicer day for testing and riding. 

I ordered a #7 slide.  It is leaner than the 6, but i think to get this perfect it is going to be a combination of going leaner in one place and richer in another somewhere with the pilot, needle and slide.  It's really close, i'm really splitting hairs here but i want the throttle response on this to be perfect everywhere and the engine running in the safe yet good performance range.  

Edited by subxero

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not sure if it is part of my problem or not but i noticed a small amount of oil and burn fuel/exhaust coming out of my compression release valve in the head.   Took it out, everything seemed ok but for some reason it is not sealing 100%.   My thought, if air can get out, then it can certainly get in no? 

So it could a be possible source of an air leak.  

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I need help my thumpstar won't start after me being out on it it only starts off a bump start and suggestion how to fix 

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10 hours ago, Matthew123 said:

I need help my thumpstar won't start after me being out on it it only starts off a bump start and suggestion how to fix 

If you are talking about a 4 stroke you are in the wrong section.  Having said that, when my 4 stroke wouldn't kick start anymore, the valves were closed and the head needed rebuilt. If you are not talking about a 4 stroke, what bike do you have? Can you give us more details about the problem?

Edited by frdbtr

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removed the decomp valve and just blocked it with a bolt and crush washer to ensure it wasn't leaking.

I was lean on the pilot and idle but fat off idle, went up to a 48 pilot, and it took a #7 slide and a DGL needle to lean out the 1/8th - 1/4 throttle.  Needle feels best in 3rd clip.  That was the magic combo.

feels really good everywhere now.  good clean idle 

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