Hey guys, I've got a 95 Yamaha Fx1 with lots of modifications, but I'm having trouble with it cutting out power under full throttle. I've determined I need to richen the carb, which is a blackjack 46mm. I've read around online that adjusting the two mixture screws will take care of the job, but other people say I'll need to rejet it. They say that fiddling around with the adjustment screws while the ski is idling will only adjust the mixture during idle, and that in order to change the mixture ratio under throttle, (which is where my problem is occurring) requires replacing the jets. If anybody could provide some feedback, I'd appreciate it.
How do I richen a carb?
- Thread starter Brett Hanson
- Start date
waxhead
wannabe backflipper
- Location
- gold coast
you could gold plate it ??
Vumad
Super Hero, with a cape!
- Location
- St. Pete, FL
Read the mikuni tuning manual. We can help you but for such simple questions, you need to start with the manual. After you've read it a dozen times and you think you got it, read it a few more. And know it never seems to work exactly like it should on paper. Every motor is different.
Bottom end is needle and seat and pilot, low screw adjusts the idle.
High end is main and high screw.
Bottom end is needle and seat and pilot, low screw adjusts the idle.
High end is main and high screw.
VXSXH20
Sionis Industries
- Location
- Mid-Atlantic
call jetworks... see what art says. He rejetted mine and mentioned that the mix screws shouldnt be opened past 7/8 to a full Turn. beyond that is to go up the next logical jet size. as mentioned , test and tune is always a bear, keep your changes small and gradual until you feel it change slightly. dont just reset all and start over. thats a bad day waiting to happen..
- Location
- Stouffville, Ontario
You may also want to want to record the changes. It's easy to forget how many turns and what you've done.
VXSXH20
Sionis Industries
- Location
- Mid-Atlantic
Yes! Well said , forgot to mention that
NVJAY775
My home away from home.
- Location
- Gardnerville, Nevada, United States
Best read you'll get on carb tuning properly. I keep a copy with me all the time, because I'm still learning myself. But I'm gaining on it!!
http://www.mikuni.com/pdf/sbn_manual.pdf
Vumad
Super Hero, with a cape!
- Location
- St. Pete, FL
If you download the kindle app, you can save it to your phone.
NVJAY775
My home away from home.
- Location
- Gardnerville, Nevada, United States
I'm on it! Thanks for the tip there. Much easier than paper. Had to reprint last season, due to a beer spill.