Carb Tuning Success Story

[motoman]

Yuppers, I'll get to the shop in the morning before work. I was waiting on your reply Motoman. Thank you. Will try the 137.5's tomorrow after work.

Several others know this stuff well also, and A couple regularly bust my chops when I get it wrong. No offense to me, as we all are here to learn.......or be corrected, as incorrect info is of no help, specially when frustration level is already at its peak.....BTDT. Let us know her what that all triggers out of it for smooth respones.........or not.

[DiverRay]

I would start with the float level! Drop it to about 26mm, as the "new gas" is lighter due to the alc. in it. You should be fine on the mains, or you may even need to go up one. But do the float level FIRST, as it has a BIG effect on the idle and top end. JMHO

[IanDMacDonald]

Interesting. Thank you Ray. I'll try the float height first, as I have great mid and top-end power, so I assume Main is good. Plus, correct me if I'm wrong, but a one size difference can be over-compensated with the mixture screws, right?

[motoman]

I would start with the float level! Drop it to about 26mm, as the "new gas" is lighter due to the alc. in it. You should be fine on the mains, or you may even need to go up one. But do the float level FIRST, as it has a BIG effect on the idle and top end. JMHO

Totally follow that theory Ray, as we've discussed that on several occassions in person. Does make sense, no doubt, its just that the alcohol level has reduced the BTU's, so a tad more fuel needed to produce the same 'work'. Would'nt that mean float levels RAISED a couple tenths from stock setting?

[IanDMacDonald]

A diamond always looks different from a different angle: if the carbs were upright, you'd drop the floats a few tenths. If the carbs were upside-down, they would then be raised a few tenths.

[motoman]

A diamond always looks different from a different angle: if the carbs were upright, you'd drop the floats a few tenths. If the carbs were upside-down, they would then be raised a few tenths.

Very true, but the suggested 26mm is lowering, any way you cut it.....

[IanDMacDonald]

I'm lowering them as we speak.

[IanDMacDonald]

I feel stupid now, as I realized from 25.7mm to 26mm is literally the thickness of a piece of paper. Will I really see any differences lowering the float height by that little?

[motoman]

I feel stupid now, as I realized from 25.7mm to 26mm is literally the thickness of a piece of paper. Will I really see any differences lowering the float height by that little?

Maybe, if you know how it was reacting before. Guess if you've went to the trouble to make that minute change, curiosity if nothing else would answer your question.

[Rasputin]

Almost time to move this thread to the proper forum. Ian had Pm'ed me and asked a few questions which I did reply to. I see some of the same questions I posed to him, asked here. He did not bother to reply to my PM.
Things like "Same goes for 'slightly modified air box', whatever that may mean." (posted by Motoman), can make a huge difference in answering to carb problems.
K+N, drilled airbox, no filter, pods ran into air box, snorkel cut or removed, Bottom half missing, special home made filter installation... we have seen them all and without info our hands are somewhat tied.
Like I say this thread has developed into other than a members lounge thread and a new one should be started.