Single carb conversion thread...

TeeCat, first of all thank you for this thread and all of the interesting information it has provided!

Secondly, Your bike looks great! Good work with the modifications.

I am currently waiting for my Joe Wiseguy 2 into 1 intake manifold and my vm 36mm roundslide. Extremely sick of my Bs38's.....

Is there any chance you could post a photo of the throttle cable at the carburetor junction please? I'm just trying to get my head around whats ahead of me!

Keep up the good work man!
 
ok, posting in this again…been having same issues with my carb. and I've pretty much got it narrowed down to the slide, for some reason i just didn't even check it at first and assumed things. anyways. my slide sleeve will not adjust down to 5/32 as a starting point. the idle screw is all the way out and its still very open! any suggestions? do i need a new slide with less cutaway?
 
So, I partook in this exercise and went ahead and did the single carb conversation this week. I have everything ready but I am still stumped on what throttle cable to use. I have the Wiseguy Bobber single intake and a brand new Mikuni VM36. Now I just need to know what cable is recommended: specs, lengths, parts numbers, manufacturers, etc... I have noticed that there were a few changes of stock cables over the years so the vague answer of "I just used part of the stock cable" doesn't cut it for what cable to get for this conversion. My bike is an 82 an didn't have any of the stock anything left when I got it. And yes I have asked a few people on this thread and gotten only 1 reply and that persons solution just doesnt work for my situation after everything was mocked up.
 

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For beginners, it is going to need an end for a Mikuni on one end and it has to be long enough. I would suggest measuring from the carb, through the bike and to the throttle where you want the cable to go in. You might use something like a piece of 1/4" nylon rope, taping it to the top of the carburetor and feeding it through the bike and up to the handlebars and allowing enough for turning slack, etc. This will give you the length of the outside casing to start with. Many/most M/C dealers in the US get parts and accessories from Parts Unlimited. PU sells 'universal kits' where you have to put both ends on the cable but you can get appropriate ends and cable inners and outers in the right length and build them yourself. PU dealers also can get Motion Pro parts and accessories. Motion Pro will make a special cable for you. You give them the measurements and the type of ends you want and they send you back a cable. The MP page is here:

http://www.motionpro.com/motorcycle/custom/
 
Does anyone have any experience using a Mikuni TM32-34 carb in a 2 into 1 conversion? It seems like a better carb than the VM32 and it has an accelerator pump.
 
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Great project. Plan to to do it myself. to summarize what was the final jetting, idle screw setting and needle jet that worked the magic?
 
I guess everyone rode off into the sunset happily ever after... Thank y'all for this thread! Will be doing this setup as soon as I can find an appropriate 2 into 1 that I'm happy with, then I'll purchase a single VM34 and begin the fun. If anyone knows where I can source one of the intakes that looks nice please let me know! I like the more forward moutning one as well. I messaged Wiseguy on instagram. If he gets back with me I'll reply in this thread again
 
I am also pursuing a 2-1 setup and looking for a manifold, I found another thread here; called and emailed Weston at Counterbalance Cycle,
http://www.xs650.com/threads/stainless-1-2-intake-manifolds-from-counter-balance-cycles.39540/
Got no reply from him and saw this thread. My issue is I have a custom frame that needs a center intake rather than a side setup like the stock frame would use. Weston did offer this originally but apparently he is not available so, is there anyone else that supply’s these for xs650’s?
 
I must admit that I struggle to see the upside of a single carb on a stock framed XS. It just looks too awkward IMHO. If the frame was more like an RD or a Rickman, a symmetrical manifold could be used without much trouble.
 
arcticXS said:
I must admit that I struggle to see the upside of a single carb on a stock framed XS. It just looks too awkward IMHO. If the frame was more like an RD or a Rickman, a symmetrical manifold could be used without much trouble.
Click to expand...
Personally, I don't think it looks too bad! I currently have 0 carbs for my XS. I am looking at a) buy and refurb a set of BS carbs b) going the GPZ500 carb set route or c) 2 into one w/ mikuni. I can't quite afford the dual Mikuni setup and I've never done any work on anything other than a single-carb setup. I was also thinking it might be easier to sell the mikuni and intake if I didn't like it versus a set of older carbs

I was thinking maybe I'd be better off with one Mikuni than 2 BS's...? It would have to be easier to dial in thanks to this thread
 
1 carb is much easier to deal with for obvious reasons, it will stay in tune without ever having to be synchronized, the throttle cable setup would also prove simpler and more reliable. For myself I am planning on using a symmetrical center feed intake with a keihin fcr which in itself is a huge advantage, I will also install a dual squirt pump nozzle that will spray right into each cylinder equally. So; better performance, more reliable and simpler are the top 3 reasons I plan on venturing down this Avenue.
 
If you look at vintage twin cylinder motorcycles with only one carb, it is always situated dead center on the head, equal-distant from the intake ports. I can't think of an exception. The rebelspirit 155 XS 650 intake referenced above just looks like a genuinely bad idea. Intake tracts, from carb to port need to be the same length just as exhaust pipes lengths from port to end of pipe should be as identical as possible. This is a very basic tuning principle.
 
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There is a guy up here in Canada that has one with an fcr carb way off to the left and backwards and he says it works wry well, fortunately my custom frame needs a center port intake so I will never know; if I can find an intake, or I may just fab and tig my own, if not.
 
hovel said:
If you look at vintage twin cylinder motorcycles with only one carb, it is always situated dead center on the head, equal-distant from the intake ports. I can't think of an exception. The rebelspirit 155 XS 650 intake referenced above just looks like a genuinely bad idea. Intake tracts, from carb to port need to be the same length just as exhaust pipes lengths from port to end of pipe should be as identical as possible. This is a very basic tuning principle.
Click to expand...
Never let science stand in the way of a bad idea...
 
Charles13 said:
I am also pursuing a 2-1 setup and looking for a manifold, I found another thread here; called and emailed Weston at Counterbalance Cycle,
http://www.xs650.com/threads/stainless-1-2-intake-manifolds-from-counter-balance-cycles.39540/
Got no reply from him and saw this thread. My issue is I have a custom frame that needs a center intake rather than a side setup like the stock frame would use. Weston did offer this originally but apparently he is not available so, is there anyone else that supply’s these for xs650’s?
Click to expand...
Greensand foundry makes a triumph style single carb intake for xs650 with an amal.
4-iron-cross-points-celtic-pentagram-generator-cover.jpg
 
I love that! I've looked at his before..not sure if I can even fit a velocity stack in between the carb and frame however
 

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