Single Carb Conversion for ST?

STgriz

The Old Bear
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Looked through the "carb" threads and didn't find anything on this topic, so here goes:

I understand the advantage of multiple (one per cylinder) carbs for high-rev performance. However, keeping four of them happy and healthy can be problematic (see other threads on "carb"). Has anyone successfully fabricated a four-pipe, single-carb mod for the ST? I have seen GoldWing conversions for a VW carb, but nothing for STs. As I age, my riding becomes more and more sedate, and I'm not sure I need an 8000 rpm redline anymore (would the old '94 hold together at extended high revs?)

Feedback welcome -

-O.G.
 

ST1100Y

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I'm pretty sure that such would only F_up the engine characteristics... problems on firing it up, idle, awkward throttle response and more issues...
That design is so much focussed on torque, that its depending on the proper gas columns... 'snorkels' to manage the stand-off, etc...

Never change a running system and that...

4-port intake manifold EFI might be a way (thinking of a 'Type 4' since we're already talking VW carbs)... lots of efforts to consider though... who fabricates and programs the ECU required...
 

sirepair

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About the quickest way to mess up a sweet-running engine, especially a carburated Honda V4, is to start jacking with the carbs. If you have the resources to do it, by all means please do! I would LOVE to see what you come up with!

Back in the 80s, I spent a lot of time and $$ messing with modifying my VF500F Interceptor. Custom Carillo rods, Wiseco 12.5/1 pistons, balanced crank, flowed heads, new cams, slotted timing sprockets and more. Did away with the air box. Got velocity stacks and separate air filters, and spent days and days jacking with jetting. Never could get it as good as stock clear across rpm range! Either torquey on bottom and flat on top, or kick butt top and no bottom. Definitely lots of tuning done with the air box.

Now, if I had a dyno, more $$ and free time, it would be fun to work on, but I would not expect results as good as stock without a lot of effort!
 

Blrfl

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First one to successfully bolt a Holley 4160 onto an 1100 gets a free pie.

--Mark
 

ST Gui

240Robert
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I remember a short craze of bolting dual Webers onto a Honda 750-4. I knew a couple of guys who actually tried it but just couldn't get proper throttle response through the entire RPM range. They tried two different manifolds but couldn't make it work. It did look cool though. Don't know if anybody ever got it right.
 
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I'd rather see EFI on an 11. I know a guy in Aurora, IL who could prolly do it, but it wouldn't be cheap. :D
 
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STgriz

STgriz

The Old Bear
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So - everybody kinda confirms what I thought I already knew - don't mess with it unless you are very bored, rich, and knowledgeable - none of which applies to me!! I didn't want to be innovative, but find out if someone else had already done the scut work. So - I will likely stick with the current setup and endure the minor headaches that occasionally arise. My ST advisor (STOC #49) tells me to trade for one with FI. Perhaps, one day . . .

Thanx all -

-O.G.
 
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So - everybody kinda confirms what I thought I already knew - don't mess with it unless you are very bored, rich, and knowledgeable - none of which applies to me!! I didn't want to be innovative, but find out if someone else had already done the scut work. So - I will likely stick with the current setup and endure the minor headaches that occasionally arise. My ST advisor (STOC #49) tells me to trade for one with FI. Perhaps, one day . . .

Thanx all -

-O.G.
Wondering just what the "minor headaches" are?? Of course, if you leave it sitting for extended periods, you will have gummed up carbs, but even that is avoidable by running the engine for several minutes at varying RPM's once a month to ensure the float bowls don't dry out. Done that with my '95 model, over winters, ever since new and have never had need to take the carbs apart yet.
 
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