ANYONE with Mikuni 26mm Starting Point?

Does your Spree/Elite already run great, and you're trying to make it quicker/faster? Need a monster motor swap? Discuss your ideas here.

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Wheelman-111
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ANYONE with Mikuni 26mm Starting Point?

Post by Wheelman-111 »

Greetings:

Same question; anyone running one of these or even a TM 24 for a guess at starting-point jets for the VM? I opened it up just today. It came with a 60 Pilot and a whopping 180 main. Or is that really all that Whopping, in Mikuni-Speak? Sheesh, my XL1200 Sportster S ran a 180. (I know Keihin CV40 - different carb, different numbering...) Still, somebody somewhere must have installed one of these, No?
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
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Wheelman-111
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Re: ANYONE with Mikuni 26mm Starting Point?

Post by Wheelman-111 »

Greetings:

Well there were just too gosh-darn many VM experts to know where to start, but I sensed 190 would be Way rich. My biggest pilot 35 and a 160 Main went in.

Problem 1: throttle cable too short caused 5000-RPM "idle".
Fixed by removing the nut from the carb top cable socket.

I am not certain about the 35 pilot. Didn't quite stall with air screw fully closed. I think it's too small because of the awkward transition to the main, which seemed about right. Better with the needle Full Rich, so I guess I need 40/155.

Documenting here for reference.

Cool float system:
MikVM26FloatSystem.jpg
MikVM26FloatSystem.jpg (1.15 MiB) Viewed 1607 times
The floats are fixed to a couple standing shafts articulating with the brass forked lever that works the needle. Less friction, more Precision.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
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LMH
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Re: ANYONE with Mikuni 26mm Starting Point?

Post by LMH »

Thats the same carb set up as a 82 Kawasaki KDX175, except its a 30mm instead of a 26. On the KDX I use a 40 pilot and 162.5 main, just for a little reference if it helps any at all.
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Wheelman-111
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Re: ANYONE with Mikuni 26mm Starting Point?

Post by Wheelman-111 »

Greetings:

BIG help, reaffirming my ballpark. Thanks, LMH!
Right now I'm thinking up or down 1 Pilot size and 155.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
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