Carburetor UCD33 - enhance fuel flow

not sure if this is the needle itself, in any case i ordered 10πŸ˜‡πŸ˜†πŸ˜Ž
 

Attachments

  • Screenshot_20230315-142809_Spark.jpg
    Screenshot_20230315-142809_Spark.jpg
    302.3 KB · Views: 84
ok all good, found the needle, shortened it by ca. 1mm, also installed 135main and 20pilot. so far all good but tomorrorw long test ride.
First picture: if you can shim there, underneath that kind of circlip, you should be ok. Try one washer first, if not sufficent put two.
 
First picture: if you can shim there, underneath that kind of circlip, you should be ok. Try one washer first, if not sufficent put two.
funny thing, the needle of the 350 has 3 rings for the circlip, the 500 needle only one so it cant be repositioned by stock means. with the very limited and shabby tools available my mechanic used an angle grinder to shave 1mm off the spiky end.
 
Needle length was not to be shortened, if it is out of the hole it no longer metering.
 
Needle length was not to be shortened, if it is out of the hole it no longer metering.
what is the difference between shortening it and adding a washer at the underside which pulls it in. in any case the bike runs fine.
 
I can not explain that, outside of my Pay scale.
@Sasa may step in πŸ€”
 
But he'd didn't so here it is. Screenshot_20230315_212042_com.ebay.mobile.jpg
You can see with these 2 needles that they are Tapered, they go into a hole and the further they come out of the hole the greater the hole size is, effectivly.
So raising the Needle is setting it up higher and therefore making that hole bigger all the time and it get bigger as it goes up as well.
Cutting it short does not change the Taper or the diameter of the Needle or I and others would recommend it.
The drill and Fine Sandpaper is what was done by Tuners, of course it would be better to have a selection of differing Taper/diameter Needles but reducing the size of the Needle with sandpaper is quick and easy to do, especially when it has just one.
 
those mikuni are compatible with ucd33 or is it just a sample picture?
they do look different but could still fit.
 

Attachments

  • 20230315_193828_copy_1024x2272.jpg
    20230315_193828_copy_1024x2272.jpg
    341.6 KB · Views: 70
  • 20230315_193804_copy_1024x2272.jpg
    20230315_193804_copy_1024x2272.jpg
    320 KB · Views: 75
those mikuni are compatible with ucd33 or is it just a sample picture?
they do look different but could still fit.
pretty easy when they are held together, should be possible to determine whether it is the same.
 
The bike is still knocking a little bit - not often but I still want that fixed so I put the needle to the drill and slimmed it with sand paper.
we will see if that works out ...
 

Attachments

  • 20230317_112616.jpg
    20230317_112616.jpg
    259.1 KB · Views: 87
Back
Top