RGS Mikuni RS36 Main Jet Size

[ksoholm]

Lads,

I have 127.5s in my stock RGS with filter pods and free-flowing mufflers on stock headers and collector. Plugs are a mite dark; could be from a spell of too-rich idle circuit, but what are you other RS36 users using for mains? I'm planning a dyno session soon for verification.

Thanks,

Kristian

 

[Laverda SF]

Please describe your exhaust and intake system ;o)

 

[piranha-bro2]

Lads,

I have 127.5s in my stock RGS with filter pods and free-flowing mufflers on stock headers and collector. Plugs are a mite dark; could be from a spell of too-rich idle circuit, but what are you other RS36 users using for mains? I'm planning a dyno session soon for verification.

Thanks,

Kristian

It's quite difficult to read a plug on modern unleaded fuels. Dark is probably fine, but a dyno sesh is definitely a must if you want it to be right.

 

[1200 JOTA]

I've tried 122.5 (at 6000') and the bike seemed to prefer the richer jet @ 127.5.

A 3 into 1 though ... and even then the pipes are a tad sooty but plugs / ports look good.

 

[ksoholm]

I've tried 122.5 (at 6000') and the bike seemed to prefer the richer jet @ 127.5.

A 3 into 1 though ... and even then the pipes are a tad sooty but plugs / ports look good.

Yeah, and that's at 6000'. I'll stick with the 127s, it's also what Red installed.

 

[hooksey]

Info posted up here previously.

 

[ksoholm]

Info posted up here previously. View attachment 58320

I searched high and low - this is perfect, thanks! Confirms my suspicions re size.

 

[redax5]

that is an old spreadsheet, for your engine if you feel 127.5 is too large, go down to the 125 mains that I supplied in the kit and try them but do not go lower without doing a dyno session to check fueling
I don't use 15 pilot jets anymore either, your carb set will have 17.5 pilots in them
Pilot jets have far more effect on the tune and running then the mains do

 

[piranha-bro2]

Pilot jets have far more effect on the tune and running then the mains do

Very difficult to get this simple fact through many people's heads.

 

[ksoholm]

that is an old spreadsheet, for your engine if you feel 127.5 is too large, go down to the 125 mains that I supplied in the kit and try them but do not go lower without doing a dyno session to check fueling
I don't use 15 pilot jets anymore either, your carb set will have 17.5 pilots in them
Pilot jets have far more effect on the tune and running then the mains do

Funny enough, after pulling the carbs to go over things I discovered the accelerator pump adjusting screw had gone AWOL. Pump was active right off idle. No wonder things got a touch sooty! Heading to dyno shortly.

 

[1200 JOTA]

Funny enough, after pulling the carbs to go over things I discovered the accelerator pump adjusting screw had gone AWOL. Pump was active right off idle. No wonder things got a touch sooty! Heading to dyno shortly.

looking forward to the results ..

 

[Vince]

Ditto