Welcome to Billys Out Back Home of V4Carbs


  • What is the difference between a kit and a plus (+) kit? 
     Price is one. The other is the type of float bowl gaskets supplied with the kit (the plus/+ indicates a pre-formed gasket). To cut costs without sacrificing quality on a kit we went with o-ring seals for the float bowls. The bowl has a channel cast around the perimeter. The o-ring seats in the channel and seals very well. We use them on our own bikes and all our carb rebuilds. We would not if we did not trust them. Some folks insist on the factory preformed style so we supply them with the + kit. They are pricy so that kit costs more. If $$$ is tight, get the non + kit. It works great. 

  • NOTE: Some models (3rd gens) do not have a compatible shape of float bowl and ONLY plus kits are available.

  • I replaced my factory air filter with a K&N filter.   Do I need to re-jet?  No, a re-jet is not necessary. A K&N flows no more air than the factory filter and if you over oil it, it will flow less.

  • I replaced my factory mufflers with aftermarket cans. Do I need to re-jet? No, a re-jet is not necessary. The factory collector supplies most of the back pressure. The collector is the metal box under the engine that all 4 header pipes lead into.

  • I am planning to install a Kerker 4-1 exhaust on my Magna. Do I need to re-jet? OH yeah! No collector, no back pressure. The engine is flowing free and will run lean. It is time to up your jetting. Talk to us, we can tell you what sizes you need.

  • Do I really need the jets in this Super kit or can I buy a cheaper version?  We have a family. We understand the value of a buck and we all work hard for our money. That's why you are looking at our ad instead of calling the Honda parts dept. So, we try to cover all the needs and budgets out there. The Super kit is our top of the line kit and is not intended for the budget minded. If you absolutely want the best kit you can buy then congrats, you found it. You can rest assured you have the correct parts for your exact yr/model/engine size. You don't have to worry about "are my jets worn beyond spec"?  Did some Dilbert before me booger them up trying to fine tune it? Most of our customers are decent wrenches but few are really carburetor experts and do not have the tools or expertise to check out their old jets. If you've ever struggled with plugged up idle jets, this kit eliminates that. Toss the old ones and install nice new clean ones. With this kit you're not just buying a carb kit. You're buying us. -Our tech support. -Our years of experience with Honda V4 carbs. -Pics and data sent to your email acct. Try calling the big guys and ask which emulsion tube goes in the right rear carburetor of your bike?

  • Why do Harleys and VTX's outrun my V45?  Three possible reasons. 1 - You actually have to shift to 2nd gear at some point in the race. 2 - You forgot to hook the rear spark plug wires back up at your last tune up. 3 - You really need to do a carburetor rebuild.

  • I am confused by all the different variations of the carb kits. How do I make sense of which one comes with what?   We added pictures and descriptions to the site that we hope will help with that. 


  •  How long does this service take?  Tough question to be specific on. It can be as little as 6 days to as long as 4 weeks. We encourage riders to send their carbs in during the off season (winter for most) when business is slow for the fastest turnaround. Send them to us in the Spring time and Summer and it will take longer because everybody wants them at the same time. During peak riding season the average wait runs appx 3 weeks. We stay very busy then and the line of racks awaiting rebuilds can get long indeed.

  • What is the difference between the Primo and Econo services? Functionally they are identical rebuilds. One works just as well as the other. The Primo has a polished,shiny exterior! The Econo is not polished. If it comes in ugly it will leave ugly but clean. Shiny is more for the Magna guys but some folks are picky about their Sabres and Interceptors and want them cosmetically nice.

  • I'm thinking about rejetting. Can you do that for me? Yes. It will cost extra. We charge $40.00 for a new set of 4 main and 4 slow jets.

  • Should I rejet? Several reasons actually. The majority of the time there is no valid reason. Honda did a great job on dialing these carbs in. If you install a header system you need to up the main and slow jets. If you primarily ride in a very cold climate, extreme heat or high altitude a rejet may be in order. We are happy to discuss it with you so that we can get it right. See the 'about us' or 'contact us' links on this site to call or email.

  • My 700cc bike has a flat spot around 5k - 6k rpms, wth? This is one Honda blew it on. It's a common problem and we suspect it had more to do with the EPA and their restrictive emissions rules. As a matter of course we will shim the main jet needles to cure this problem. All of our carb kits come with these shims for the DIY'er.

  • My carbs are leaking fuel down the sides. 30 + yr old rubber seals are way past their use by date. The fuel tube seals and the float bowl seals harden and crack resulting in leaks. Our rebuilds replace all seals and you should be good to go for another 20 + years.

  • My carbs are dumping fuel out the rear overflow and/or is flooding badly. It's a float valve assy problem. It may just be dirt caught in the needle/seat area and sometimes a soft tap on the sides of the bowls with a screwdriver handle will fix it (temporarily). The problem is, the float needles have rubber tips which are 30 + yrs old. They are hard and maybe worn causing a poor seal. The other problem is the opposite end of the float needles have a spring loaded pin. The spring is weak/worn out and the pin is likely corroding which can cause intermittent hanging up of the float. Our rebuild service replaces all this for a long term fix. We will add this. If your bike has these symptoms check your oil for the presence of fuel. It will leak past an open intake valve, pour onto the piston and leak past the rings into the crankcase. Gasoline makes a very poor lubricant and can cause a spun main/rod bearing. Dump the oil and filter and fix the carb issues before adding fresh oil.

  • My bike won't idle unless I add choke or idles rough and dies when I touch the throttle.90% of our rebuild work is directly related to this problem. You have dirty/clogged idle circuits. Causes are: dirty gas, clogged/damaged fuel filter, and the biggie is the bike sat up for an extended period unprepped for storage. The new Ethanol blended fuels are notorious for separating out the chemicals and clogging your idle circuits.

  • How do I avoid the long term storage problems with Ethanol fuels? You can run marine grade fuel stabilizers and that will certainly help but the best way is just drain the bowls. Shut off the petcock if so equipped.

  • Will I need to do anything else to my carbs after install? The carbs are set as perfect as is possible on the bench. The trouble is every engine varies. Carbon deposits, ring wear, valve wear, valve adjustment variations, minute vacuum leaks etc all cause compression variations which affect the vacuum that is seen on each cylinder. There are also variances caused by temperature and altitude. This is why a vacuum synch and pilot screw adjust must be performed for optimal performance. They will normally run well out of the box and definitely much better than when they came off the bike but if you want perfection you gotta do the extra work. You will get better throttle response and mileage/power with a good vacuum synch and idle air/fuel mixture adjustment.