SuzukiSavage.com - Carb Confusion

DrunkenDwarf

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Re: Carb Confusion
Reply #30 - 08/08/10 at 11:38:32

Serowbot wrote on 08/01/10 at 13:30:02:

Give a suck on the vacuum line,... if you get gas,(don't swallow)... the diaphragm is leaky and you need a new petcock,... if you don't get any gas, you need a new hose...

Installed new hose, tried the suck test. No gas. However, it still exhibits the same behavior that ralfyguy demonstrated.

A pinched vacuum hose results in a higher RPM than a free one. Undecided

Can someone else try this? I'd prefer to have more than 2 data points before blaming both our petcocks.

Serowbot wrote on 07/28/10 at 20:14:01:

To test the main, accelerate from 30 or 40 mph, in 4th or 5th gear at full throttle for several seconds, then reduce throttle by about 1/8,...if power increases for a second, you are lean on the main jet. Go up one jet size and test again.

Tried this again today. I don't have throttle positions marked currently, so I had to guess on the 1/8.
30mph in 4th gear. Man the engine was at a low RPM. I'm usually shifting from 2 to 3 at this point. Slammed open the throttle, engine sounds like a jack hammer. Wait a few seconds (about 10 mph faster) and closed the throttle slightly. The engine sounds got "smoother", there wasn't an obvious change in acceleration.

-D. Dwarf

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Pearl White 2007 S40; Dyna exhaust; Current jets: 52.5 w/ bleed (2 turns out) / 1.5mm (0.06") spacer / 150; raptor petcock

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justin_o_guy2 Serious Thumper Offline What happened? Posts: 55279 East Texas, 1/2 dallas/la.	Re: Carb Confusion Reply #31 - 08/08/10 at 12:23:03 30 mph in 4th & slappin WFO isnt okay, IMO,, 40 mph, maybe, but 30 is gonna lug thecrap outta the thing. You could accelerate gently from there, butWFO dont seem okay. Id have top go try it, & mines shut down rightnow.
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Routy Serious Thumper Offline SuzukiSavage.com Rocks! Posts: 2280 Winston Oregon Gender:	Re: Carb Confusion Reply #32 - 08/09/10 at 05:29:19 Agreed, I would never go WOT at 30-40 in 4th or 5th. And you don't have to. Start at 60 in 5th, go WOT 10 seconds max, then quickly back of to 1/2 throttle. If its running rich at all, there will be a very noticeable stumble for a second before leveling out.
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bill67 Serious Thumper Offline old tired Posts: 8517 genoa city wisconsin Gender:	Re: Carb Confusion Reply #33 - 08/09/10 at 05:38:42 I go wot at 40mph in 5th a lot thats what I like to do,It really pulls strong.It pulls strong at 35 but I think thats a little low rpm for the engine.
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ralfyguy

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Re: Carb Confusion
Reply #34 - 08/09/10 at 07:07:59

bill67 wrote on 08/09/10 at 05:38:42:

I go wot at 40mph in 5th a lot thats what I like to do,It really pulls strong.It pulls strong at 35 but I think thats a little low rpm for the engine.

I kinda ride the same way. If I'm not in a hurry. But it does pull strong from 40mph in 5th. In fact it pulls from 40-70 in under 10 seconds. That's what I like about the bike. Torque! Displacement not spoilers! Cheesy

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DrunkenDwarf Senior Member Offline Morning Zombie Posts: 325 Seattle, WA Gender:	Re: Carb Confusion Reply #35 - 08/09/10 at 15:40:15 It seems I got some bad advice. Oh well. -D. Dwarf
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Routy

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Re: Carb Confusion
Reply #36 - 08/09/10 at 17:34:47

Well no kidding Bill,....what ever brought you to that conclusion ?
It couldn't have been because its trying to hammer the crankshaft out of it.... now could it ? Ride anyway you want, its your lower end thats being hammered ! Good thing they are tough, huh ?
bill67 wrote on 08/09/10 at 05:38:42:

I go wot at 40mph in 5th a lot thats what I like to do,It really pulls strong.It pulls strong at 35 but I think thats a little low rpm for the engine.

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Rich
'07 S40 Blvd stocker, except drilled OEM exhaust and white spacer mod...1/2 (.055)

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Jay

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Re: Carb Confusion
Reply #37 - 08/11/10 at 20:03:13

OK, I have a question. Warning: I'm dumber than a box of rocks on carbs. An earlier post said if it pops more in humid weather, it's running rich. Everytime it clouds up that's what mine does. It also does a bit of a stumble at stop lights, but never dies on me. I'm in Fort Worth, Texas, no idea my elevation; no previous owner, my carb and bike are stock, except for the idle screw adjust, and my pipes are turning a nice golden hue. I've been frusrtated with my mpg (it steadily dropped after breakin from 55 to about 48mpg where it's rested ever since.) Anything I should be concerned about?

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Jay

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LANCER Serious Thumper Alliance Member Offline Savage Beast Performance Parts Posts: 10661 Oklahoma Gender:	Re: Carb Confusion Reply #38 - 08/12/10 at 02:16:17 DrunkenDwarf wrote on 08/09/10 at 15:40:15: It seems I got some bad advice. Oh well. -D. Dwarf you're still having the same issue with it ?
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DrunkenDwarf

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Re: Carb Confusion
Reply #39 - 08/12/10 at 09:16:40

LANCER wrote on 08/12/10 at 02:16:17:

DrunkenDwarf wrote on 08/09/10 at 15:40:15:

It seems I got some bad advice.
Oh well.

-D. Dwarf

you're still having the same issue with it ?

I haven't been able to ride much recently - failed inspection - no front brakes left. Getting pads today (FA106), I'll do the job over the weekend.

I replaced the vacuum hose but it still does that weird RPM pick up with the vacuum hose pinched. I have no good explanation. Either the petcock has a slight leak and I must not suck hard enough. Shocked

Or...???

re: spark plug
http://www.4secondsflat.com/Spark_plug_reading.html
Mine looks pretty close to example #2 on this page, which supports verslagen1 suggestions in post #3. A leaky petcock could be a contributing factor.

So yes, nothings change and I'm still learning.

-D. Dwarf

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Pearl White 2007 S40; Dyna exhaust; Current jets: 52.5 w/ bleed (2 turns out) / 1.5mm (0.06") spacer / 150; raptor petcock

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DrunkenDwarf

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Re: Carb Confusion
Reply #40 - 08/18/10 at 09:36:02

On the road again!
Yay for new brakes. So much quieter.

Back to the issues at hand. Actually, I need to gather some data and I'll probably make a new thread.

Talked to an old shovelhead mechanic. He thought it was an intake leak. He could be right. I did use an impact driver on the screws on the top of the carb - without removing the carb. Dumb, I know.

Anyway, no one else is willing to pinch their vacuum tube? Sad

-D. Dwarf

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Pearl White 2007 S40; Dyna exhaust; Current jets: 52.5 w/ bleed (2 turns out) / 1.5mm (0.06") spacer / 150; raptor petcock

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ralfyguy Serious Thumper Offline Posts: 932	Re: Carb Confusion Reply #41 - 08/18/10 at 10:37:17 DrunkenDwarf wrote on 08/18/10 at 09:36:02: Anyway, no one else is willing to pinch their vacuum tube? -D. Dwarf I'm curious about that too. I wanna know if this is normal
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Routy

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Re: Carb Confusion
Reply #42 - 08/19/10 at 05:34:36

I did it for someone some time back. There was no change at all.
Of course it is not normal !,....how could it be normal unless there was a vacuum leak ? Think ! Shocked

ralfyguy wrote on 08/18/10 at 10:37:17:

DrunkenDwarf wrote on 08/18/10 at 09:36:02:

Anyway, no one else is willing to pinch their vacuum tube? Sad

-D. Dwarf

I'm curious about that too. I wanna know if this is normal

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Rich
'07 S40 Blvd stocker, except drilled OEM exhaust and white spacer mod...1/2 (.055)

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DrunkenDwarf Senior Member Offline Morning Zombie Posts: 325 Seattle, WA Gender:	Re: Carb Confusion Reply #43 - 08/19/10 at 06:40:12 Routy wrote on 08/19/10 at 05:34:36: I did it for someone some time back. There was no change at all. Of course it is not normal !,....how could it be normal unless there was a vacuum leak ? Think ! Vacuum leak? Intake leak? Petcock leak? All three? Guess I've got some leak hunting ahead of me. -D. Dwarf
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