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smallest mikuni for a UL

Post Wed Apr 07, 2010 6:36 pm

Posts: 83
Any of you guys are using a smaller than 34mm mikuni in your U model.
Just got a 30mm round slide mikuni and was wondering if it is possible/practical using it in a stock UL...the carburetor has the standard factory jetting (pilot 40, main 250, slide 2.5, needle 159 6F5, needle jet P5, air jet 2.0)
I have the victory library book but the suggestions for 74" displacement doesn't include the VM 30mm...
Any suggestions appreciated!

Post Wed Apr 07, 2010 9:06 pm

Last edited by panic on Sun Nov 28, 2010 6:20 pm, edited 1 time in total.

Post Thu Apr 08, 2010 7:11 am

Posts: 83
Thanks, I thought the same about the slide. Any suggestions for the needle/needle jet?

Post Thu Apr 08, 2010 7:37 am

Last edited by panic on Sun Nov 28, 2010 6:20 pm, edited 1 time in total.

Post Thu Apr 08, 2010 2:39 pm

Posts: 83

Post Fri Apr 09, 2010 4:42 pm

Posts: 51
what jetting would you suggest for the 34mm Mikuni on my stock 41U ?
Thank you, Tom

Post Fri Apr 09, 2010 7:10 pm

Posts: 83
I highly recommend you buying the "Mikuni Tuning Harley-Davidsons" from Victory Library.
I bought mine from their website
This book has the info you need, including the exact jets for a UL.
AFAIK the writer is a board member, right panic?

Post Fri Apr 09, 2010 7:17 pm

Posts: 83
You carburetor is a VM round slide? I forgot to add, the book covers mainly round slide VM Mikunis.

Post Sat Apr 10, 2010 12:00 am

Glad to hear you found it useful, but yes, it's for VM round slides only.

Post Sat Apr 10, 2010 8:06 am

Posts: 51
thank you for the link, helsingborg.
I will order the book as soon I can get some $ notes here in Spain. ( I don't have paypal).
Yes, I have the VM round slide Mikuni.

Post Tue Apr 13, 2010 6:43 pm

Posts: 12
I just put a 38mm VM on a 42 UL, and have some unreal cranking problems that turned out to be the most expensive little nothing. It cranks, runs like a dream, idles so slow I wonder if it will keep running, and I changed nothing from the stock needle and jets it came with. Plugs look wonderful, and I ain't even in Kansas. I did change the throttle cable that came with it by reversing a Harley cable and threading the end of the ninety. Works great.

By the way, there is a comprehensive VM tuning Manual on Mikuni's web site you can download for free. I have Victory's manual also, and it is a good one.

This is the link for the free tuning manual download. ... 20Carb.pdf

You are going to love that VM!


Post Wed May 05, 2010 6:18 am

Posts: 51
got my Mikuni Tuning from Victory Library today. WOW - it only tooks 3 days to Spain. Compared with Germany that takes 12 days :?
Will keep me in trouble for a while to translate and understand everything. Thanks again for the link :)

Post Wed May 05, 2010 8:59 pm

Posts: 976
Location: Markt Einersheim, Germany

Anythng coming to Germany takes does sending anything from here.

Sorry....just had to comment. :oops:


Post Wed May 05, 2010 11:47 pm

Posts: 1654
don't know about Germany, but we did pass by Helsingborg last week, I was a week late joining the vessel because of the volcano. I'll wave as we go back through.... :D

waiter, waiter, there's volcanic ash in my soup
yes,sir, it's a no-fly zone...
Shoot, a man could have a good weekend in Dallas with all that stuff...

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