Bruzer, look in the tech articles and look down to carb re-jetting.

http://roadstarclinic.com/content/view/60/96/

Thats one link to the jetting page, but you'll get the idea till some one on here wakes op from their hangover...

Did that help any?

Go to the menu here and go to the Road star riders forum more people run the 42 there I have read about the connection between the carb and the manifold not easy to seal causing alot of problems an air leak there will cause major problems.Also my understanding is that the speedstar mikunis are set up to run with the tps and the fuel pump other Mikunis bought else where are not and I assume your was not a speed star .The tech section has a write up on the VOES setup for the 42 and 45 carbs that replaces the TPS.Also there was a guy on RSR that used to setup the carbs to use the TPS for a fee plus shipping ask around but not sure if he still does it.Knowing your jetting setup would be helpful as well.I run the 40 sooooo all I can do is tell you what I have read ...good luck....and let us know how it goes as some here will probably do the same ...Coug

thanks, I got it going still over flowing. I think it is related to the fuel pump, might Have to go to gravity have bent tab in float tried differnt jetting as directed maybe not enough? Runs like a bag of !#*@, think this one may be fr the shop to figure out even down to the after market cables seems to be a lot of slop in them i have maxed them out still sloppy. when I blip the throtle no response lot of burping through the pipes on decel, and throught the carb on excel its been a long day any ideas are welcome PLEASE help if you think you can

Bruzer, get some carb cleaner, with the straw so you can direct it, and lightly spray around all the joints in the carb and manifold while it's idling. If it increases the rpm you have a vacuum leak. I would also get a lenGth of fuel hose and run direct from the petcock to the carb just to see how it runs with gravity feed. be sure to unplug the fuel pump.

This link should get you to a tuning guide, it should put you in the ball park...http://mikuni.com/fs-tuning_guide.html

Don't worry about the tps if you don't have one, the timing will revert to WOT if the tps is not hooked up..won't hurt anything at all accept you will loose a little bit of torque at the very bottom, not hardly noticable..What is the setup you have now?

these jet settings should get you close..l

Needle Manufacturer: Mikuni
Needle Clip: 3
Jet Manufacturer: Mikuni
Main Jet Size: 167
Pilot Jet Size: 25
PMS Screw Manufacturer: Mikuni
PMS Turns Out: 1.75


use the tuning guide for float settings, I don't recall what it is..hope this helps...

hotelfox wrote:
Flashback wrote:
What size float valve do you have? If the carb is setup for gravity feed (most are, unless they are a speedstar version), the fuel pump will not work with it..forces fuel past the needle...you will either need to remove the pump, or change to a smaller float valve...

Hey Flashback,
I just put that 2.5mm float valve in my carb and kept the fuel pump, so far no problems, are you telling me to watch for some? I didn't like the sound of that
The bike seems to be running good so far...
Howie


Well, You want to keep an eye on it as that's a pretty big orfice to be using with a pump..It's not recommended but it obviously works for you...

Day 2 starting to think winter is early I am going to try these tips and see what happens? might blow up,hope not focus and Ill get there its just so many stories melt downs blown springs ydayadayada sop here goes tear it apart and build again any input on intake manifolds?

No tps (mikuni42m) but do have dyna3k The jet is 160 can change as barons provided kit 167.5? bubs shortys with vortex baffle (awsome sound retarded loud)update... overflow has stopped (but it did last time) switched to a 167.5 jet factory mikuni needle set at I believe on the 3rd notch should this be changed? starts well, bad hesitation on the blip, backfiring tad of flame through pipe got the cable set much tighter now full throtle roll little sticky (lub I guess)any way improving still felling lost though.

I put a Barron's ported manifold on, I belive you could port it yourself if you had the time and the tools, now I have a spare manifold to play with some day.
Seemed to help I guess, who knows, I just spend money on shiny parts and have no idea if they make my bike faster, better or anything else. I know its loud as all hell.....lol.