Single carb conversion thread...

the throttle cable that is on there is the one that came with it. Its made for a harley and it has a really funky housing on the throttle end, i cant seem to find a throttle that fits with it
 
Well, depending upon what throttle you're using - mine's stock - I got one of Mike's two-into-one cables for Mikuni VMs, and removed one of the cables at the junction tube. It seems to work fine. You may have different length requirements because of your bars, though... but maybe not, because of the forward position of your carb.

TC
 
twins, I think I see how that might happen, depending upon how the particular cable is built. In this case, the little nylon disk is more like a "plug" that's tapered toward the bottom, so binding seems like less of a possibility. Might have to cut one cable, though, because the housing seems pressed or otherwise attached to the base of the metal tube. I'll examine it more closely.

joe-wiseguy has indicated that this works. If it does not, I'll try your other suggestion, though my local bike shops never fail to disappoint me, even when I am looking for something as simple as a cable.

i just have to reply here. i'm a broke ass rat-bike guy from canada. bicycle cables work awesome. the derailleur cable for a mountain bike fits right into any throttle mech i've tried. i've been using one all year(about 20000kms) with no issues. i bought a set of old side pull brakes, and mounted the cable retainer nut to the part on the carb where the other end of the throttle cable hooks up. i've also used a mountain bike brake cable for a clutch cable as a temp fix(will give you about 500kms of use) to get me home on tours using the same setup. i actually keep a spare derailleur cable and a spare brake cable in my tool kit. just in case. buying all brand new stuff will set you back maybe 20 bucks at your local bicycle shop. i now prefer the bicycle cable for a throttle, cause i get to dial in the length perfectly.damn, i wish i had a pic o this.
 
btw. i forkin love you guys. i'm just teaching myself how to do ze maintenance. i'm a self proclaimed welder/fabricator(take a look at me bike, lemme kno wat you thinks). so tuning is new to me. i have long wanted a single carb setup to eliminate vacuum syncing as i'm a bit of a gypsy, so i want a machine that needs as few tools as possible. methinks this one thread will answer aboot 90% of the questions i'll ever ask. cheers!

FORKIN EH!!!!
 
Well, I hope it's helpful to you. I was hoping that this thread might prove to be contributive to the forum, as I have taken a lot from here.

I like your ideas about bicycle cable! We're kindred spirits, as I also like to repurpose existing parts, as you can see from pics of both sides of my conversion. Automotive/hot rod parts have adapted nicely to this project with a little massaging on the bandsaw and some hand tools.

And welcome!

TC
 
ok I am seriously considering a long tube (tunnel ram) style merged intake and I was thinking that I could get away with a carb off an 883 Sporty.... any thoughts?
 
Hey TC can you give me the exact jetting specs that you used for your carb, mains, pilots, needles, i need a good place to start cause right now my carb has a 500 main in it so i have no clue where to begin my quest
 
Be interesting to see the differance in the jetting for the longer inlet track, do mikuni have a differant jetting system?, 500 sounds huge,
 
your right, that is huge, the carb came off a harley sportster so the jetting is way off, thats why i need some specs to give me a place to start, I havnt even tried to start the bike but im sure it wouldnt run with that 500 in there
 
Sorry for the delayed response:

- air screw currently @1 turn out
- main air correction jet in intake bell: removed
- pilot jet: 25
- main jet: 200
- 159-P8 needle jet/6F9 needle (clip in middle slot)

These are for a Mikuni VM36 Round Slide... I'm not sure that they will apply to your carb or intake.

TC
 
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yeah i don't think it will be exactly the same but at least this gives me a good point of reference. there isnt alot of info about this topic out there so ill take any help i can get
 
Uh, TC, to avoid confusion, I'd suggest that you not use the abbreviation "RS" to refer to a Mikuni round slide carburetor. In Mikuni talk, "RS" means "Radial Smoothbore." The RS series carbs are dedicated 4-stroke flat slide pumpers, sold in banks of 4. Mikuni HSR carbs (for Hardly Ablesons) and TM36/68 pumpers belong to this design group, but are designated differently, since they're sold as single carburetors.
 
Hello TC I won a new updraft Zenith on E-Bay for $27. It i new and looks to be what I need. I want try until I finish my project. I also won two 35 volt and 31,000 uf capacitors
so I can run without a battery. I will post a picture of the carb soon. Tony C the other TC
 
Tony... good to see you. :) Good going! I'm anxious to see what you have in mind!

I got mine just about dialed in and then... winter showed up. :( So she sits on the battery tender. It's too cold to even undertake my braided fuel line project, even with the little heater on out there. :(
 
hi guys,,,i,ve been reading our site about 2 into 1 inlets made by joe wiseguy... somebody said he also made 1 so that the carby sat under the side cover .. i looked on his site ,,but unfortunately nothing was there ...and has anybady used these with a single 38 cv carby... .... any help would be greatly appreciated ... also i luv the ram set up that he makes .... although i proberly have an accident due to watching the carbys out the front of the cylinder head.. ,,and what do you run ,,,ram tubes or oval filters or tapers and again could you use 38cv on the ram set up ... anyway it looks great... regards oldbiker
 
ohbee... if he makes anything like the one you mention, it's news to me. Getting the carb behind the cover would pose a challenge.

Also, someone on here, maybe in this thread, was wanting to use a BS38 for this application. I think the educated consensus is that it will work beautifully as long as the runners are not too long; the vacuum-operated 38 slide needs a vacuum signal that's sufficient for optimal functioning.

In case you missed my piccies, here is my induction setup that I built from Spectre Performance automotive induction parts.

TC
 

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i luv...your set up of the direct pull carby and the bend for the air cleaner... ,i got an email from joe ... about doing 2 into 1 manifolds for 38cv carbys and he said he was looking at that down the track... hopefully not toooooo far down the track ,,i think the standard throttle cable for 38,s would shift side enough to do a good job ... finally i do luv.. the ram set up twin carbs out the front of the head.. although i would tend to ride along watching my carbys ..regards oldbiker
 
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