Joined
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8 Posts
Hello Everyone,
This journey of mine to get my 06 750 to function has been an insane uphill battle and now that I can see the light at the end of the tunnel I am relieved that I found a solution and can talk about it like an expert. There was a lot of trial and error that came along with this modification and it still isn't perfect but with more time and patience I believe this could be a suitable replacement for the horrible stock carburetors.
This story begins with the purchase of a used 06 vn750 with 2000 miles on it. The first thing I knew I would have to do is pull carbs since the bike had sat for a few years. The carbs on a stock vn750 are not fun to pull out and that's when I come to this forum looking for an airbox mod and found out about the ear shave, well the earshave did not work out for me like I thought it would, too many vacuum and reliability issues to consider the mod a success. so I found myself in a situation where I could either reinstall the OEM airbox/emissions components or continue to mess around with the twin carbs.
That's where the idea of a single carb comes in, I knew some people on this forum had tried it before but nobody documented much beyond a few quick videos and answering questions.
So let's get into it.
I live in Las Vegas - 2,001 Elevation (For reference in regards to jetting)
You will need
Vn750 Single Carb Manifold
Throttle Cables for CV40 ( These worked good but you might want to consider just a bit more length 115cm or 120cm if you can find it)
Choke Cable CV40
CV40 Carburetor
Air Filter & Mount (Without Sportster bracket)
Emgo Crankcase Filter (Optional See Step 2)
1. Get rid of all OEM Emissions and Airbox connections, tubing, Carburetors, etc.
2. You will need to Vent your Crankcase to the Atmosphere or you can connect it to the Airfilter that is linked above with the supplied fitting you just have to attach a 3/8 hose to the original hose and route it.
NOTE: If you decide to vent to atmosphere put an emgo filter on it and connect it to the side of the bike. Emgo Crankcase Filter
3. Get rid of your factory carb boots (the Manifold kit listed above comes with boots.)
4. Remove OEM Choke Cable & Throttle Cables
5. Plug or Coaster the Reed Valves
6. Install (Video will come later today)
Running 170 Main, 42 Idle for the Jets
Tuning:
This part is where you are on your own, frankly, we just made a major modification to the air and fuel intake of this engine. Your climate, elevation, bikes age, mileage, and exhaust will affect how well this runs on the low end and top end, You may gain or lose power but now you have a setup where removing the carb bowl take 2 minutes and you can test new jets, filters and gas/ethanol blends to your hearts content without spending the whole day pulling the dual carbs out of the most awkward configuration I've ever experienced on a bike.
This is a big modification and if you're not the tinkering type then I don't recommend you do this to your own bike. There are many variables that this write-up cannot control and it's up to you to decide if the time and effort it will take to make these changes are worth it.
In my personal situation, it is, the stock carbs don't work for me and by the time I realized my mistake I had already invested a large amount of time and money into the earshave that I wasn't willing to sacrifice so I made my own solution and I think it works great. I don't know how your bike will run but I will advise you that my bike, a 2006 with very low mileage runs great with this configuration.
Look forward to the video where I will go over some more pros/cons and you can see what the bike looks and sounds like.
I also plan to do some ride testing and videos so you can see acceleration and throttle response on the low and high end. Maybe stick it on the dyno and get it tuned 100% by a local shop.
Side Note:
There is also a Mikuni version of this mod but I have not tried it yet.
This journey of mine to get my 06 750 to function has been an insane uphill battle and now that I can see the light at the end of the tunnel I am relieved that I found a solution and can talk about it like an expert. There was a lot of trial and error that came along with this modification and it still isn't perfect but with more time and patience I believe this could be a suitable replacement for the horrible stock carburetors.
This story begins with the purchase of a used 06 vn750 with 2000 miles on it. The first thing I knew I would have to do is pull carbs since the bike had sat for a few years. The carbs on a stock vn750 are not fun to pull out and that's when I come to this forum looking for an airbox mod and found out about the ear shave, well the earshave did not work out for me like I thought it would, too many vacuum and reliability issues to consider the mod a success. so I found myself in a situation where I could either reinstall the OEM airbox/emissions components or continue to mess around with the twin carbs.
That's where the idea of a single carb comes in, I knew some people on this forum had tried it before but nobody documented much beyond a few quick videos and answering questions.
So let's get into it.
I live in Las Vegas - 2,001 Elevation (For reference in regards to jetting)
You will need
Vn750 Single Carb Manifold
Throttle Cables for CV40 ( These worked good but you might want to consider just a bit more length 115cm or 120cm if you can find it)
Choke Cable CV40
CV40 Carburetor
Air Filter & Mount (Without Sportster bracket)
Emgo Crankcase Filter (Optional See Step 2)
1. Get rid of all OEM Emissions and Airbox connections, tubing, Carburetors, etc.
2. You will need to Vent your Crankcase to the Atmosphere or you can connect it to the Airfilter that is linked above with the supplied fitting you just have to attach a 3/8 hose to the original hose and route it.
NOTE: If you decide to vent to atmosphere put an emgo filter on it and connect it to the side of the bike. Emgo Crankcase Filter
3. Get rid of your factory carb boots (the Manifold kit listed above comes with boots.)
4. Remove OEM Choke Cable & Throttle Cables
5. Plug or Coaster the Reed Valves
6. Install (Video will come later today)
Running 170 Main, 42 Idle for the Jets
Tuning:
This part is where you are on your own, frankly, we just made a major modification to the air and fuel intake of this engine. Your climate, elevation, bikes age, mileage, and exhaust will affect how well this runs on the low end and top end, You may gain or lose power but now you have a setup where removing the carb bowl take 2 minutes and you can test new jets, filters and gas/ethanol blends to your hearts content without spending the whole day pulling the dual carbs out of the most awkward configuration I've ever experienced on a bike.
This is a big modification and if you're not the tinkering type then I don't recommend you do this to your own bike. There are many variables that this write-up cannot control and it's up to you to decide if the time and effort it will take to make these changes are worth it.
In my personal situation, it is, the stock carbs don't work for me and by the time I realized my mistake I had already invested a large amount of time and money into the earshave that I wasn't willing to sacrifice so I made my own solution and I think it works great. I don't know how your bike will run but I will advise you that my bike, a 2006 with very low mileage runs great with this configuration.
Look forward to the video where I will go over some more pros/cons and you can see what the bike looks and sounds like.
I also plan to do some ride testing and videos so you can see acceleration and throttle response on the low and high end. Maybe stick it on the dyno and get it tuned 100% by a local shop.
Side Note:
There is also a Mikuni version of this mod but I have not tried it yet.
