Topic: I need help setting up my turbo 550 with ARD and electronic ignition!!

[Old75_ratafe]

Why would you think it would handle poorly?

Actually looking at the new pics I retract that statement lol.  The previous pics I didn't see the turbo tucked and it just looked bulky and cobbled together but now that its coming back together looks pretty well thought out.

[jon®2004]

IT RUNS!!!!!!!
Thanks to 68grandprix's advice! I had the #1 plug wire on the #4 post on the distributer.... After I got the wires sorted it fired right up with no carb and starting fluid!

The distributor is a Mallory and yes the cap has a notch on one side. I was able to find a new cap a rotor at Napa and in their books it was under a VW part number, the bike also came with all of the build paper work. Which had part what kind of parts were used. The problem with the carb is Weber no longer makes it, I contacted the weber carbs direct and guy had never seen one. There's no room to run a duel side draft, even with one sticking off the side. I hooked the carb up and the bike ran as it did before I took it apart, not to good. The carb leaks tons of fuel, which is a float issue?? Also the bike won't stay running. I'm going to do more tinkering tomorrow. I'd like to get a newer carb that is more reliable, I'll post pics of the throat and measurements tomorrow.

Any how, it works like it did, which means I put it back together right! Thanks again guys!!!!!!
jon®

[jon®2004]

The only markings on the carb are:
WEBER EW (top) 32 OF 1/200 (side)

If that means anything, I've done searches online and found nothing.
jon®

[scottly]

IT RUNS!!!!!!!

WooHoo!!!!
 I would look for a carb from an XR500 or maybe an FT500...

[Tintop]

thanks for the info jon.  Will see what I can find out from my vintage car sources.

As for Weber, they don't make a lot of things any more in my experience, as in support for their vintage products.   Most of them now weren't born when DCOE's were 1st made!

My point was that just like this forum there are ones for old Fiats and such.  If you can find out the carb's application, someone at that forum will either know were parts are, or a good direct sustitute.  Sounds like figuring out the application is the trick.

[68grandprix]

Awesome. One hurdle cleared. I have seen some turbo bike guys use Harley carbs. Even if the bolt pattern/throat don't match up, it might be worth it to make an adapter, just so you could use a semi-modern carb you can get parts for. Jim

[scottly]

The distributor is a Mallory and yes the cap has a notch on one side.
the bike also came with all of the build paper work.

Did this include the instructions for the Mallory? The aftermarket distributors often had adjustable advance curves. Turbos usually need less total advance.

[754]

A lot of turbos used S&S or SU harley carbs.. but most were onm bikes 850cc or bigger. If you grab a HD Keihin carb (not the CV type), you can probably work with that...they are cheap & plentiful..

 I think that carb is a DCOE cut in half, dont know how they kept the fuel inside it..

[scottly]

 I think that carb is a DCOE cut in half, dont know how they kept the fuel inside it..

That's what I thought, too, Frank, but the more I looked at the pics the less it looked like a DCOE. No round cover over the jets, which would have also been cut in half?

[754]

 On the old thread on this. LA swap meet, there were pics..

 Anyway, my thoughts were if it was cut down that the whole 2nd venturi bore is cut/ground off.. then the fuel supply holes from the bowl to venturi was plugged off.. was what I thought happened..

[BLUE71TURBO]

 I'd run a mikuni carb on it. Maybe 36mm flat slide.   

[jon®2004]

Something like this:

http://cgi.ebay.com/ebaymotors/Yamaha-YZ125-YZ-125-36mm-36-Mikuni-Carburetor-1999-2000-_W0QQcmdZViewItemQQhashZitem4aa48d8f9eQQitemZ320588320670QQptZMotorcyclesQ5fPartsQ5fAccessories#ht_500wt_948

[BLUE71TURBO]

  No, for a little more money you can get a " NEW " nice flat slide mikuni 36mm like this.............

            http://cgi.ebay.com/ebaymotors/New-Mikuni-Flat-Slide-36mm-Carburetor-ATV-MX-Dirt-Bike-/250077588233?pt=Motorcycles_Parts_Accessories&hash=item3a39c92b09

[jon®2004]

Is this going to ruin the coolness factor at all using a newer style carb?

[jon®2004]

Also, how would that fit to the intake? I'm guessing some kind of flange with rubber boot?

[754]

To the best of my knowledge, 2 stroke carbs have different needle profile & slide cutaways..

 Save the hassle, and start with a 4 stroke carb..

[jon®2004]

What is a good 4 stroke carb?

[jon®2004]

The carb I have now only measures 33MM on the front opening, and I think its the same on the rear. Should I get the 33mm Mikuni 4 stroke with the rubber flange mounts? Will this give me enough fuel? The intake opening is only so big...

[L.A. Nomad........]

Congrats on buying the bike and it looks great!

If you get it running, do you plan to ride it around to any events?

L.A. Nomad

[jon®2004]

I do plan on showing it, i think it's turning out very nice. Once I get this carb figured out I will have the bike out alot!
Thanks!
jon®

[BLUE71TURBO]

To the best of my knowledge, 2 stroke carbs have different needle profile & slide cutaways..

 Save the hassle, and start with a 4 stroke carb..

 The flatslide that i posted is for a 4 stroke engine.  A friend of mine has 4 40mm mikuni flat slides with accelerator
  pumps on his drag bike.  They work real good !

        http://www.cheapcycleparts.com/products/49104-mikuni-tm36-2-carburetors-mikuni-tm-tmx-flat-valve-carb-36mm

       http://www.sudco.com/vol33/37.pdf

[BLUE71TURBO]

What is a good 4 stroke carb?

   JON, The best mikuni carb for turbocharging is the HSR series. The only problem for you is the smallest is 42mm ,
   way to big for a 550 cc engine.  As for the cool factor, forget it. You need a carb that will function right or you'll
   burn that sucker to the ground.  Which ever carb you use you must inspect your spark plugs through all of the
   driving ranges. It also matters on how much max boost pressure you are gonna run .
    Draw-through turbo systems really like good fuel circuitry for idle, off idle and transition to full throttle. You should
   also look into using a CV ( CONSTANT VELOCITY ) carb. They worrk good to. Also some really good insurance would
   be to install a water/fuel  injection system to help when on boost. Call MR. TURBO and get more advice, cant hurt.
       Last but not least, get a book titled (  MOTORCYLE TURBOCHARGING, SUPERCHARGING & NITROUS OXCIDE )
   You'll be glad you did !!  Good luck my turbo brother !!  
    P.S.  The book is by JOE HAILE .

[jon®2004]

UPDATE...
I took the carb apart and found the original set-up notes from the builder. I reset the mixture screws and float height based on the notes. (I think I did, I'm not sure which is the idle and high speed screws but I made a guess) The bike runs, and idles nicely! Only issue I have now is the carb is leaking from the very bottom, there's a part that has a arm that when full throttle is applied the arms pushes up in a diaphragm (make since)? This part looks very similar to other side draft weber carbs, so I'm gonna take a chance a order the replacement parts and hope they fit.

All that's left now is a few odds and ends (gauges need mounted, throttle arm needs finished, tins need painted)

What do you guys think of the plug wires sitting on top the engine? will these hold up to the heat? If not I will have to think of a way to hold them up.

Thanks again for the help!!

[scottly]

UPDATE...
 I'm not sure which is the idle and high speed screws but I made a guess) The bike runs, and idles nicely!

The webs I'm used to have only idle mixture screws and idle speed screws.

 Only issue I have now is the carb is leaking from the very bottom, there's a part that has a arm that when full throttle is applied the arms pushes up in a diaphragm (make since)? This part looks very similar to other side draft weber carbs, so I'm gonna take a chance a order the replacement parts and hope they fit.

That sounds like an accelerator pump diaphragm on your carb, however the DCOE carbs use a piston pump. The square plate on the bottom of these carbs just seals the bottom of the float bowl. There is no lever or diaphragm, just a gasket. Pics please!! 

[754]

A good silicon plug wire, tied in a knot around an exhaust header on a 4-1 should not burn through or get hurt..

 On top of motor is fine, if you can get them thru the cylinders near the cam cavity, then arc them up to the plugs.. looks really cool and clean.
 What I meant earlier by not using the CV carb off HD was, that I dont know anything about them.. and do know that some used the 38mm  HD Keihin on turbo setups..