OP
@coastalviews avatar
UTC

Enthusiast
P125X
Joined: UTC
Posts: 66
Location: San DIego, CA
 
Enthusiast
@coastalviews avatar
P125X
Joined: UTC
Posts: 66
Location: San DIego, CA
UTC quote
So ive had the 177/road2/26.26/drilled heart, kit up and running for the past week as I break it in with the following jets:

Idle 52-140 - Turned idle up, mixer screw all the way in, backed it out until it no longer affected the rpms, lowered the idle.


AC140 - i was using a 120 up until today.
BE4
125mj

Starts up on the 2nd or third kick with no choke, maybe just a slight twist of the throttle, then idles by itself.

The throttle is very responsive, and crisp off idle, but once I start getting on it, I get sputtering/spluttering(sounds like its blowing a raspberry) through 1/4-3/4 or so. I havent even gotten it to WOT since im on 35mph city streets. The plug looks dark brown, and the air filter has fuel on the inside of it.

I don't mind running a little rich if it means a cooler engine, and less chance of a seize. This isn't a performance build. But the noise sounds like crap.

I was thinking maybe stepping down the mixer, since I have yet to hear anyone running a 177 with an AC larger than the 140.

Any ideas where to start?
⚠️ Last edited by coastalviews on UTC; edited 1 time
@peeteboy2 avatar
UTC

Hooked
1980 P125x 2002 Bajaj Chetak
Joined: UTC
Posts: 151
Location: Southern California, but Crete is where my heart is!
 
Hooked
@peeteboy2 avatar
1980 P125x 2002 Bajaj Chetak
Joined: UTC
Posts: 151
Location: Southern California, but Crete is where my heart is!
UTC quote
Your idle is the same as your air corrector? Maybe you know something I don't and that would explain my jetting problems
OP
@coastalviews avatar
UTC

Enthusiast
P125X
Joined: UTC
Posts: 66
Location: San DIego, CA
 
Enthusiast
@coastalviews avatar
P125X
Joined: UTC
Posts: 66
Location: San DIego, CA
UTC quote
Peeteboy2 wrote:
Your idle is the same as your air corrector? Maybe you know something I don't and that would explain my jetting problems
Nope! Just a bonehead mistake. Sorry i couldnt help ya! Laughing emoticon
UTC

Jet Eye Master
PX221 MHR, PX200 O tuned, PX181 M1XL, PX125 O tuned and some motorbikes
Joined: UTC
Posts: 4825
Location: London UK
 
Jet Eye Master
PX221 MHR, PX200 O tuned, PX181 M1XL, PX125 O tuned and some motorbikes
Joined: UTC
Posts: 4825
Location: London UK
UTC quote
Put the AC120 back in. Reduce the MJ from 125 until the raspberry sound goes away.
OP
@coastalviews avatar
UTC

Enthusiast
P125X
Joined: UTC
Posts: 66
Location: San DIego, CA
 
Enthusiast
@coastalviews avatar
P125X
Joined: UTC
Posts: 66
Location: San DIego, CA
UTC quote
I put the 120 back in and stepped the 25 down to 23. It seemed to run slightly better. I noticed it's sputtering when I'm barely to 1/4 throttle, but can roll the throttle right through it, and the sputtering disappears.
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