Hitchcocks Forum

Hi all
hope someone can help,I have rebuilt bike after many years and am having trouble getting carb sorted. its jetted to manual,but have used cut down car airfilter to go into original filter box(original was mesh and felt I think).
Bike starts OK but when trying test ride it dies when throttle opened, ok in first gear but changed up and gave it some throttle and it was if it was choking,it also spits back in carb when choke taken off.any ideas please.
just a thought ,would it give these symptems if auto advance not operating( it has distributor,bob weights no5t working ??

Sounds to me like it can't breath mate (i.e. can't get enough air) just like you and me if somebody tried to choke us. What's it like if you remove the air filter altogether?

'Ello, 'Ello !!! ----------- Wot's goin on 'ere then ???? Have we been EDITED ???....didn't you have this query just recently ?? ----------- I know I gave a post for it.

hi ALANR got to cover all avenues
old git

Fair comment, shipmate !!----Hope the info helps.

Sounds like its running far too weak when throttle opened. quick test is to gradually close the choke lever on a steady half throttle and see if it improves the power delivery. Your enriching the mixture by this method so if symptoms worsen then your running too rich to start with...... Try and fit the proper filter.... check the carb to head flange for proper sealing and that its not been distorted by over tightening...... check throttle slide for wear/good sliding fit... and correct fuel level in float chamber.... should be level with the metal pip found under the word "amal" on the inspection plate............ amal 375, bore size 25/32" Pilot=25 cutaway=3.5 main jet= 100
needle=0.11 position/groove 3.............. Just check the auto advance for free movement and snappy return.... Used to own a 66 3TA, was a nice bike.