Performance Carb Upgrade

I bought a dellorto phbg 16 mm for 92 bux but have to machine a bushing for the ht. It has to be tuned with jets etc but is highly tuneable in ALL aspects unlike the sha.
 
All of the after-market carbs seem to have a common problem. It's hard to get them lean enough.
My NT carb works reasonably well after jetting down to 0.73 and lowering the slide needle to it's lowest setting. Even with this stock carb, it would be nice to go a shade leaner for mid-range RPM.
I tried lowering the float level by 1mm, but then the engine started to go dead for a moment on tight corners or after a small jump or wheelie.
Does anyone know of a slightly leaner replacement slide needle, or slide needle and needle jet?
Even a slightly different taper would help.

... Steve
 
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Which carb did you buy, Dellorto clone or Mikuni?

Specifically, where did you get the power increase, bottom-end, mid-range, top-end, all of the above?

Has your comfortable slow speed decreased? By how much?

Has you top speed increased? By how much?

I just fitted a RSE billet head and am wondering whether to also get a better carb.
... Steve.

hi,
my rse motor has the dellorto carb an is fully tuneable its got 2 screws ,1 to idle
1 for fuel intake
an yes u can add a bigger inlet jet
my power comes on when i touch the throttle ...
ohhh its the hp1 50cc but with billett head an coated piston ....
an like u i live in syd
 
hi,
my rse motor has the dellorto carb an is fully tuneable its got 2 screws ,1 to idle
1 for fuel intake
an yes u can add a bigger inlet jet
my power comes on when i touch the throttle ...
ohhh its the hp1 50cc but with billett head an coated piston ....
an like u i live in syd

I like the idea of a separate idle circuit with an idle mixture screw. that's what I used to like about Mikunis on my dirt bikes - fully tuneable. They even had a replaceable pilot jet.
I might get in touch with Tony and see what alternative parts are available, both for his Mikuni and Dellorto 16/16 clone .
Dellorto 5mm jets fit the NT carby, but I've heard that the Dellorto clone takes 6mm jets. Not sure about availability.
From my experience with the NT, it would also be good if alternative slide needles and/or needle jets were available.

What's the advantage of a ceramic-coated piston, apart from lower wear?
They cost a few $.
Does it also reduce cylinder wall wear?
How's the performance compared to std pistons?
I checked them out on the RSE site, but didn't know the full benefits, (if any).
I'll buy almost anything that will make my bike more reliable, more tractable or safer, ie. a decent chain tensioner - I'm making that next.

I've heard a couple of descriptions of your bike. It sounds pretty good. From memory, you have the poo-poo pipe. Does it improve bottom end much and does it detract from top speed much?

I've got a mate in Taren Point that I visit regularly - I'd like a bike reliable enough to ride up now and then. Might be pushing it, but I'll see...

... Steve
 
I got the CNS carb from spooky tooth yesterday. I didn't get home til midnight last night so, I started installing it last night but, I didn't get a chance to test it out. My first impressions are good. The carb seems to be well made (certainly better than my stock carb) and it installed fairly easily.

I'm not quite sure where to mount the choke lever though. For some reason the choke cable is about a foot shorter than the throttle cable. I have a classic style beach cruiser frame and the clamp is too small for the top tube and to big for the thinner stringers on the side. I think what I'll do is put a rubber spacer made from a strip of old inner tube around the stringer and then put the clamp around that. It'll be mounted kind of like the shifters on this bike

http://www.todayandtomorrow.net/wp-content/uploads/2009/01/ariel_schlesinger.jpg

I'll take pictures and post them once I have everything installed the way I want it.
 
Well, I got the carb all tuned up a couple nights ago. It did take a little adjusting. It ran OK out of the box but, it ran great after I tuned it up. It's been raining the last two days and it's supposed to rain tonight too so, I haven't had a chance to really take it for a ride or take pictures. The weather is supposed to be clear tomorrow so I intend to ride it to work and run it through it's paces.
 
I just got this carb, have not tried it yet. Still on the build portion of my 3rd. It may be a while. If you find the carb useful, please post!
 
I'll be interested to hear what you think of it, Dan, (danlandberg).

I wonder how bigdan's is running?

I've been thinking about a better performing carb to complement the shift kit, have to do a bit of reading. There are a few around, but some don't come too highly recommended. Not sure if that's because the carbs are no good or that the tuners lack experience.

... Steve
 
:-/I'm curious to see how this carb works also. This build is looking like a long one, this D.I.Y. from B.B. is not what you think it would be. The stock carb that came with the kit has a throttle cable issue (to close to the top tube) These D.I.Y. kits need to be modified to much for the average joe. I'm good at mods, but with out the resources it's a little tougher!:mad: But it will get done!! If I get a chance I will post pics of this one. It's still snowing here, so no big hurry for me, but I'm sure my friends would like to see it done (it's in their kitchen)!!!:whistle:
 
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