Help! cl77 carb-Needle Jet Holder position

[dux66]

rpr851r

The stock needles that i found were the exact size as the ones i was running from the keyster carb kit. Changing the needles did not solve the problem. I had also tried the 140 jet size before. but everything seemed to change when i un pluged the exhaust. I attached a picture of my baffles and one of my plugs. ( i beleave these are stock baffles for cl77s????) Please tell me what you think of the color of the spark plugs (they are D-8HA plugs) so as it stands right now i am running 42 slow jets 140 main jets and open exhaust. And the bike is running very good. this does not seem right to me but this is my first 305 and i am learning alot. I think i may even try the 145 mains, that will depend on the fourms opinion of the plugs.
Thanks again for the help
AAron

[dux66]

here are the baffles that i removed. are they from a cl77 or where they used on cl72s?

[davomoto]

Sounds like it is over jetted, too rich. Free flowing exhaust requires bigger jets, as do free flowing air filters. I suggest you re-install baffles and air cleaners, and with the orig needles, try experimenting with groove positions again. 135 main to start.

davomoto

[Phil-UK]

Hi

Just my experience ( which is very limited compared with others ) :-

My CB72 had similar issues and I also noticed that the actual needle jet was sticking out into the
throat of the carb by a different amount on each carb, so I pulled apart all the carbs I had.
The needle jets seemed to all be the same length but the carb castings seemed to vary slightly
so when you pressed the jet in it could sit at slightly different heights and on 1 carb it was a
considerable difference.
A side effect of this is that the main jet holder, which screws into the carb body and butts up
against the needle jet, then also sticks out into the float area by different amounts.
I made the stupid mistake on 1 carb of over tightening the main jet holder to try and bed it down
and it cracked the carb body where it screwed in.
Selecting the parts and bodies to get as clsoe a match as possible on both carbs made a
noticeable improvement.

Its worth noting that when I rebuilt mine I had a selection of carbs and no idea if any had
actually come off this particular bike.


FWIW .. Phil

[dux66]

Phil/dave

Thanks for the help guys. Dave i will keep working with the carbs till i get it right. I have been sent out of town for work for a few weeks so the bike will have to sit for a while. Thanks for all the great info and i will let you know what i find when i return. One thing that i have not mentioned about this issue is that I am using 100LL fuel for the bike. would running 100LL effect the way the bike should be jetted??.
AAron

[sotxbill]

make sure the gas cap is vented as well so it doesnt starve on hard long accelleration.

[jarl1967]

not to distract from the current dialogue...but back to my original question for a minute.

Am i reading that my needle jet holders (see previous pic.) are improperly installed? thread is supposed to be visible? would appreciate a clarification on that.

so far i am having no luck determining why i am only running on one cylinder, was hoping it was a carb issue but beginning to think it must be a piston/ring issue....way over my abilities, unfortunately.