Topic: Single Carb Manifold?

[Gearheadgreg]

Here is a Bad case of fuel puddling   

[Gearheadgreg]

I've thought this would be an alternative to the dwindling out supply of worn out 35f carbs.

I have a flat slide I have thought would work if I fab'd a manifold, but a friend says it will rob performance.


Anyone got info on this modification?   Will it, or has it worked?

I have a single HSR 45 flatslide on my 6 cylinder Valk, I have a Mikuni specialist building a larger excel pump for it now, he is welding in a larger pump chamber into the float bowl i have a flat spot in 5th gear when i hammer it,, here is his site may give you some ideas, been waiting 2 months for my new bowl!!! http://www.v-performance.com/products/air_fuel.html#mikuni_carbs

[Terry in Australia]

its his exhaust running out the back look in the project shop on the reverse port project. it should work just fine he didn't just go sticking an exhaust on the opposite sides he flipped the valves to the other side and needed to get a custom cam grounded so that the exhaust lifts where the intake lifted and the intake lifted where the exhaust does. should work that way there is no reversing of anything. in principle  it should work just a matter of getting the afr right it will be taking in allot more air.

by no reversing od anything i mean the cam chain still runs the same direction

Is that right mate? I read the whole thread and must have missed where he said he'd had a whole new camshaft built to reverse the intake/exhaust function, I did read where someone mentioned that there was not enough aluminum in the combustion chambers to hog out the exhaust valve seats to accept the larger inlet valves, and I saw no mention of how he was going to replace the aluminum on the inlet side and then install new seats, could you give me a link to where he did all that, or are you just assuming that it was done?

Not wanting to put a damper on your enthusiasm, I just don't think that Joey has any idea of what level of engineering is involved in this project.

[dave500]

a piston ported two stroke will run backwards easy with an ignition timing change.

[Terry in Australia]

It doesn't have run backwards Dave, Peter "Porky" Allan ran at least one reversed head Kawasaki Z1 powered drag bike back in the day, but it was a huge engineering task.

The Dohc engines are probably easier to do, as you can probably (I'm guessing) swap the inlet and exhaust cams, but a SOHC engine would be a lot trickier, as you'd have to make an entirely new cam to re-phase the lobes to do the opposite of what they're doing now, i.e., instead of opening an exhaust valve, opening an inlet valve etc. Cheers, Terry.  

[mlinder]

I've thought this would be an alternative to the dwindling out supply of worn out 35f carbs.

I have a flat slide I have thought would work if I fab'd a manifold, but a friend says it will rob performance.


Anyone got info on this modification?   Will it, or has it worked?

 What you are seeing in this pic is the exhaust..........http://www.dotheton.com/forum/index.php?topic=19961.0


but of course I have been wrong before ........

its his exhaust running out the back look in the project shop on the reverse port project. it should work just fine he didn't just go sticking an exhaust on the opposite sides he flipped the valves to the other side and needed to get a custom cam grounded so that the exhaust lifts where the intake lifted and the intake lifted where the exhaust does. should work that way there is no reversing of anything. in principle  it should work just a matter of getting the afr right it will be taking in allot more air.

by no reversing od anything i mean the cam chain still runs the same direction

Youdoundestandthefuel has tobepressurized too, right?

[KeithB]

The single carb idea is probably a bad one.
However, a dual carb manifold, one for 1-2 and one for 3-4 could be a lot easier to fab correctly.
Just a thouight...

[joeyputt]

I just found this thread, I understand it is an old thread however for future readers I thought I would clear the air a little about the engine in question in the photo that started this discussion. The engine is not running a single carburetor, the intake manifold that you are discussing is actually the beginning of the header that I built.

I do call it a reverse port as in the ports are changing their roles with the intake ports becoming the exhaust ports and the exhaust ports becoming the intake ports, the cylinder head is not turned and is still in its stock location however to answer one of the questions that seems to be of interest the cam chain does still turn in its stock direction and is not reversed, the reverse port title is in referance to reversing the roles of the ports and the airflow throught the head.

While I have not revealed the internal modifications of this engine to everyone they are not quite as complicated as some may think however they are very time consuming especially when they are being built by hand as I have always done.

Also to answer the question of seeing this engine with different intakes on it if you would like to read the build thread on this engine and motorcycle the explanation is there however for those of you that do not know this engine is very special to me as I have owned it for around 25 years, when I first decided to rebuild it I was planning on leaving it in its stock configuration however after I started the build I decided to take it back down and build the reverse port as it is something I have always wanted to do and with this engine being as special as it is to me and I plan on keeping it forever I thought she deserved something special. It is all in the build thread.

As far as the carburetors go they do not need pressurizing on this particular build.

I must thank the overwhelming majority of the members here for their support of this project, as for the few that have questioned my or the engines abilities there will be an unveiling with several videos very soon as well as a few other special things that we have planned in her honor.

I do have a build thread for her here on SOHC4 if any one else is interested in more photos or discussion please visit this link in the project shop http://forums.sohc4.net/index.php?topic=80234.650 I am getting ready to take her apart for painting, polishing, and final assembly however for anyone that is interested to see how the engine looks in its current configuration this is how she is resting now.

[lucky]

I've thought this would be an alternative to the dwindling out supply of worn out 35f carbs.

I have a flat slide I have thought would work if I fab'd a manifold, but a friend says it will rob performance.


Anyone got info on this modification?   Will it, or has it worked?

I have a single HSR 45 flatslide on my 6 cylinder Valk, I have a Mikuni specialist building a larger excel pump for it now, he is welding in a larger pump chamber into the float bowl i have a flat spot in 5th gear when i hammer it,, here is his site may give you some ideas, been waiting 2 months for my new bowl!!! http://www.v-performance.com/products/air_fuel.html#mikuni_carbs

Nice set up Greg!!!