19 PHBG boggy on take off, shitty idle

Chris Rice /

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Mar 27, 2009 01:58AM

I've come to the conclusion that I need a smaller idle jet.

Running a light weight porting 70cc Airsal, Estoril Pipe, 19 PHBG, 22mm Bennasar intake, Malossi Red horn bendy filter, case matched on an E50.

I'm running a w7 needle on the 3rd notch (second richest). Main jet is an 86, idle jet is a 45.

The take off is boggy, twist the grip bog city. Ease on the throttle and let it creep over 1/4 and the mid range is great, pulls hard up to top speed. Top end is fine too although I might need to downjet again.

My bike is idling wierd. It revs and slows. Once I run it full throttle and come to a stop it wants to die and doesn't really surge. The surging thing is when I first start it up...

I've sprayed carb cleaner on every connection of the carb bottom end, cyclinder, head, etc... Can't find an air leak.

I had the same issue on the 2nd notch. Haven't tried all the way lean on the needle, but that scares me. I also have a w8 needle that I could use. The w8 is a leaner needle right?

I also have a 48 and 50 idle if you are thinking that I need to go richer, but I feel like it's getting too much fuel at idle...

I already ordered a 42, 40 and 38 idle jet. but I won't have it until next week.

Thanks in advance for any insight.

Chris

Re: 19 PHBG boggy on take off, shitty idle

Sunset Paul /

prodrigues

Mar 27, 2009 02:14AM

it its only crappy on take off and idle you could try lowering the needle since you got it on the rich side and that mainly affects the lower throttle positions. I like to play with the needle, to see which way the jet should go, change it and do it again.

Re: 19 PHBG boggy on take off, shitty idle

Chris Rice /

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chrisr OP

Mar 27, 2009 02:38AM

I thought the needle was mid range?

Re: 19 PHBG boggy on take off, shitty idle

poo /

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michaelt

Mar 27, 2009 03:32AM

Drop your idle jet down. How does it act without a filter.

Re: 19 PHBG boggy on take off, shitty idle

Sunset Paul /

prodrigues

Mar 27, 2009 03:40AM

i'm dum

Re: 19 PHBG boggy on take off, shitty idle

Tracy /

tracy

Mar 27, 2009 07:01AM

Screw the mix screw all the way in and see if it runs better, If it runs better, but not up to par, downjet(idle) more. If it runs best with the mix screw all the way out, upjet. My opinion is you're on the right track. Alot of peeps say that there bikes like really little idle jets, but my metra65'd e50 likes a 48 the best.

Re: 19 PHBG boggy on take off, shitty idle

Jesse -B /

jtbechtold

Mar 27, 2009 09:24AM

with my 70cc k-star I had this problem went down to a 42 idle jet. I am also running a w9 needle on the leanest setting.

Re: 19 PHBG boggy on take off, shitty idle

Chris Rice /

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chrisr OP

Mar 27, 2009 10:17AM

I haven't tried it without an air filter...

Re: 19 PHBG boggy on take off, shitty idle

Chris Rice /

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chrisr OP

Mar 27, 2009 10:24AM

It runs shitty with the screw out and it's still boggy with it all the way in. I was pretty sure that I was on the right track, but wanted some opinions...

Would leaning out the needle help at all? if so, is my w8 going to make for a leaner mix at idle? At this point I'm just thinking of things to do now, since I won't have my idle jets until next week...

Re: 19 PHBG boggy on take off, shitty idle

paul /

vdubbin

Mar 27, 2009 10:27AM

w8 would make it run leaner.. cause its fatter

Re: 19 PHBG boggy on take off, shitty idle

Chris Rice /

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chrisr OP

Mar 27, 2009 10:28AM

That's what I though... But does the needle effect idle at all? My mid range is sick as is.

Re: 19 PHBG boggy on take off, shitty idle

weeder /

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timr

Mar 27, 2009 10:34AM

Check your email buddy!

Re: 19 PHBG boggy on take off, shitty idle

Chris Rice /

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chrisr OP

Mar 27, 2009 10:37AM

Nice. Is that manual posted in the wiki? If not you should post it dood. Thanks! I still wanna hear people's opinions. Shay and I agree that the idle jet is too big. I tried to tune it for about 2 hours last night at the shop.

Re: 19 PHBG boggy on take off, shitty idle

mike Thomas /

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michaelt

Mar 27, 2009 11:43AM

The problem is not your needle, drop to a 42 jet (from your description of how it behaves with the mixture screw)

Re: 19 PHBG boggy on take off, shitty idle

paul /

vdubbin

Mar 27, 2009 12:28PM

use this how to...

http://www.mopedarmy.com/wiki/PHBG_tuning_made_easy._%28a_step_by_step_guide%29

Re: 19 PHBG boggy on take off, shitty idle

Chris Rice /

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chrisr OP

Mar 27, 2009 12:49PM

I am doing that for sure. I'm just wondering if the needle can lean out the idle so that it doesn't suck so bad riding it for the next week before my jets come in.

Re: 19 PHBG boggy on take off, shitty idle

Chris Rice /

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chrisr OP

Mar 27, 2009 12:50PM

I got all that. Thanks...

Re: 19 PHBG boggy on take off, shitty idle

Chris Rice /

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chrisr OP

Mar 27, 2009 12:51PM

My question at this point is:

Will a fatter needle lean out the idle up to 1/4 throttle at all?

Answer that and I'll buy you a beer at Whiskey Business.

Re: 19 PHBG boggy on take off, shitty idle

weeder /

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timr

Mar 27, 2009 12:56PM

no.

the needle only starts affecting the fuel metering after 1/4 throttle. its in the manual i sent you!

Re: 19 PHBG boggy on take off, shitty idle

weeder /

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timr

Mar 27, 2009 12:57PM

Page 4 Figure 2

Re: 19 PHBG boggy on take off, shitty idle

Chris Rice /

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chrisr OP

Mar 27, 2009 01:00PM

I know that it says that, but that doesn't mean that it's not possible...

if the height of the slide (ie idle screw) effects the idle and the needle goes through the center of the slide, you would think that it would effect the idle to have a fatter needle...

The main jet has to effect idle somewhat.

What about the throttle slide cutaway?

Chris Rice /

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chrisr OP

Mar 27, 2009 01:04PM

I noticed that there are different slide available with different amount cut away... Which way is leaner on the slide? lower number or higher number on the slide?

Re: What about the throttle slide cutaway?

Shalerrr rrr /

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shaler

Mar 27, 2009 01:14PM

dont change that needle, and definitely dont lean it out. its the idle jet. most people dont mess with the slide or emulsion tubes anyway.

Re: What about the throttle slide cutaway?

Chris Rice /

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chrisr OP

Mar 27, 2009 02:18PM

cool... I'll wait for smaller idle jets. Anybody got a 42 or 40 laying around?

Re: What about the throttle slide cutaway?

justin turner /

onlythebest131

Mar 27, 2009 04:28PM

play with your timing a bit and adjust your mixture screw.

Re: What about the throttle slide cutaway?

Chris Rice /

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chrisr OP

Mar 27, 2009 04:44PM

I'm planning on not fucking with the timing... I like to keep my timing stock... The mixture screw is rich all the way in and kills the bike if it's backed out more than 2 turns...

Re: What about the throttle slide cutaway?

Chris Rice /

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chrisr OP

Mar 27, 2009 04:46PM

That sounded mean. All I'm saying is that I prefer not to advance my timing to fix a jetting issue... Thanks for the ideas though. Maybe I will do it just to see what happens.

Re: What about the throttle slide cutaway?

bryan /

thefishstop

Mar 27, 2009 06:31PM

you will run much better with more timiing and you only wont it out 1/2 to 1 turn if you are stock timing if you advacne it i bet it will take that jet

Re: 19 PHBG boggy on take off, shitty idle

Novakarl /

novakarl

Mar 28, 2009 12:38PM

If you make it run right when you take off, it could go dangerously lean at high RPM.

You need more fuel at high RPM regardless of throttle opening.

One thing that kinda helped me, is making the clutch grab later, but this isn't really a fix, it's a workaround. It did help with the bogging though.

Re: 19 PHBG boggy on take off, shitty idle

justin turner /

onlythebest131

Mar 28, 2009 12:57PM

I did not mean change the timing.

I meant to say, make sure your timing is good and your spark is proper.

I had a phbg doing the same thing and i couldnt figure out why, i had great spark, my jetting was spot on( after i ported like crazy) it just ran like shit and i couldnt figure it out..

First i changed my exhaust because with the porting the bullet just couldnt do what i ported for. Changed to a proma and bla dow! porting and exhaust and clutch has to all work together.

you have any more exhaust to t4y out>?

anything lower than a 45 just seems too small with a ported and case matched e50. your mixture screw is sensitive, you gotta do it like a 1/8 turn at a atime.

also your condenser might be worn out.

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