Performance Carb Upgrade

[danlandberg]

speed carb

The carb I got is the ''speed'' with a red air filter. I don't know how many parts are out there for these carbs. The only difference you notice (visually) is the fuel in let, it is a banjo style fitting with a fuel shut off. With out a way to measure throat dia. You can't see a difference. They are advertised as a carb for the 66/80cc engines. They should be jetted for such. (I hope). I can hardly wait till I get this build done. Weather is still not quite right for riding so no worries. + still waiting on a new front mount, need to drop the engine down a bit. The stock intake man. is a tough fit but the aluminum one I got seems to be better + portable. (to bad the carb or intake don't come with an O ring seal).But you can get one at any auto store. Got the slant head for this build + chamber (some from S.B.P + Some from P.B.). Hope to get it done soon, want one Moore thing (front suspension fork). These D.I.Y. kits should lack the water bottle mounts. (They are in the way!)

 

[AussieSteve]

Dan, for a really good seal, file a groove about 1mm from the end of the alloy inlet tube, to fit an 'o' ring onto the tube, rather than pressing against the end of it.
More here if you're interested.

Form the look of the 'Speed' carb, I'd say that the jets could well be the same as previous NT carbs, 5mm Dellorto. Other spare parts might be harder.

To measure the bore, you only need to measure the slide diameter. It should be the same size as the bore. They claim 3mm larger than stock. My stock NT is 14mm, so their's should weigh in at 17mm.

You'll have to let us know how it goes.

 

[danlandberg]

How much of an offset is the manafold? Might be the cure for the cable issue (to close to the top tube).

 

[AussieSteve]

Check out their site, Dan.
I had a look earlier. There's a pic of one mounted, on their site. The carb sits beside the seat tube.
Might be just what you're looking for. It has a good offset, but is very long compared to stock.

 

[danlandberg]

I had a look at the offset set up. manifold is pretty long. Still might be the ticket though. I guess you won't know till you try. Keep on biken Steve, and be double safe, one for you and one for me! cause I don't know how!!

 

[AussieSteve]

Bloody long, isn't it? Just the same, it has a good offset. (Pity they're not slightly shorter and cast alloy, but life wasn't meant to be too easy.)

You're kidding - you know I fell on my head the other week. I haven't fully learned how to be safe yet, although that helped. Helmets only here, now

 

[danlandberg]

True, life is not easy. But I agree cast would be good. The pic of your "filed" O ring grove looks like machine quality. Great job!!!

 

[danlandberg]

I'm not worried about falling on my head (unless I get sued for street damage). Hope you did not get hurt!

 

[danlandberg]

Whats a helmet?

 

[AussieSteve]

I've got 50 spare 'o' rings here now. (I'll never run out.)
If I had equipment to machine grooves, I'd knock up a few 'o' ring inlets for people. Don't trust my eyes and hand-filing skills enough, though. Could have up to 1/3 or 1/4 failures.
My only equipment is an electric drill and a low power Dremel type tool.