View or Hide Header -->
Welcome,
Guest
. Please
login
or
register
.
1 Hour
1 Day
1 Week
1 Month
Forever
Login with username, password and session length
This topic
This board
A7 & A10 Engine
A7 1946-1950
Gearbox, Clutch, Primary
Frame
Lucas, Ignition, Charging, Electrical
Amal, Carburation
Entire forum
Google
Home
Help
Search
Contact
Login
Register
The BSA A7-A10 Forum
»
Technical (Descriptive Topic Titles - Stay on Topic)
»
Amal, Carburation
»
A7 shooting star 376 mono carb setting no filter
« previous
next »
Print
Pages: [
1
]
Go Down
Author
Topic: A7 shooting star 376 mono carb setting no filter (Read 780 times)
Hughsie
A's Good Friend
Join Date: May 2015
Posts: 53
Karma: 0
BSA A7 500cc Alloy head, 55 engine 57 frame.
A7 shooting star 376 mono carb setting no filter
«
on:
25.09. 2023 18:30 »
Hi all
Is anyone running a A7 shooting star with a monobloc and no air filter? If so what jets are you running?????
It’s a new replacement 1” 376 monoblock. I need to fix the full throttle then I will play with the idol as I think my settings are way out.
To add more context I’ve posted a few times regarding my running issues. I was running a too rich but I’ve realised now thanks to previous comments that’s mainly on idle that issue as I had just been riding around my town getting used to things.
I took it out to a longer road and I’ve a real lack of power over 1/2 throttle and up.
I’ve just check valve clearance with a friend and these were a bit tight so these have been adjusted.
Someone said to me they think a main jet for no air filter should be way up in the 300-400 range!!! I’m currently running a 250!
Standard book settings is 270 but I’m not sure if that’s with an air filter, I am just running a bell mouth with fairly open pipes on short reverse cones
My settings were taken from the book for a SS
So
3.5 cutaway
106 needle
30 pilot
250 main
No air filter
Standard down pipes with short mega phone cones ends.
Endless thanks again for any suggestions, hopefully someone is actually running a similar set up on theirs I can use as a guide.
Logged
Stirlingshire Scotland 🏴
Facebook: Scottish Cafe Racers
Instagram: Scottish Cafe Racer
BSA A7 500cc Alloy head, 55 engine 57 frame.
muskrat
Global Moderator
Wise & Enlightened
Join Date: Jul 2009
Posts: 11062
Karma: 132
Lithgow NSW Oz
Re: A7 shooting star 376 mono carb setting no filter
«
Reply #1 on:
25.09. 2023 20:16 »
G'day Hughsie.
I can't give you definite jet sizes but I'd try a 300 main. It's better/safer to start rich and go down.
You really need to do plug chops at 1/2, 3/4 and full throttle.
You don't say the needle clip position.
Cheers
Logged
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
Australia
Muskys Plunger A7
Hughsie
A's Good Friend
Join Date: May 2015
Posts: 53
Karma: 0
BSA A7 500cc Alloy head, 55 engine 57 frame.
Re: A7 shooting star 376 mono carb setting no filter
«
Reply #2 on:
25.09. 2023 22:11 »
I had the needle in the middle, I’ve dropped it 1 recently but I can’t help but feel there is something far wrong with no power, spluttering anything after 1/2 a turn, just doesn’t go
I like the idea of a 300 just to see if it makes a difference.
Logged
Stirlingshire Scotland 🏴
Facebook: Scottish Cafe Racers
Instagram: Scottish Cafe Racer
BSA A7 500cc Alloy head, 55 engine 57 frame.
berger
Wise & Enlightened
Join Date: Nov 2017
Posts: 3271
Karma: 22
keith.uk 500sscafe.norbsa JDM honda 750fz
Re: A7 shooting star 376 mono carb setting no filter
«
Reply #3 on:
25.09. 2023 22:58 »
mine runs ok without a filter and with the standard 270 main jet so if your points gap is correct and timed at 3/8ths btdc try a 270
Logged
Hughsie
A's Good Friend
Join Date: May 2015
Posts: 53
Karma: 0
BSA A7 500cc Alloy head, 55 engine 57 frame.
Re: A7 shooting star 376 mono carb setting no filter
«
Reply #4 on:
26.09. 2023 09:07 »
Thanks Berger, that’s great to know
Logged
Stirlingshire Scotland 🏴
Facebook: Scottish Cafe Racers
Instagram: Scottish Cafe Racer
BSA A7 500cc Alloy head, 55 engine 57 frame.
BSA500
Resident Legend
Join Date: Dec 2007
Posts: 934
Karma: 4
Tonbridge,Kent,UK
Re: A7 shooting star 376 mono carb setting no filter
«
Reply #5 on:
26.09. 2023 13:00 »
270 on mine as well
Logged
1960 A7 (57 motor to SS spec)
Hughsie
A's Good Friend
Join Date: May 2015
Posts: 53
Karma: 0
BSA A7 500cc Alloy head, 55 engine 57 frame.
Re: A7 shooting star 376 mono carb setting no filter
«
Reply #6 on:
01.10. 2023 19:48 »
Increased to the 270 now and feel an improvement, thanks for the feedback.
Logged
Stirlingshire Scotland 🏴
Facebook: Scottish Cafe Racers
Instagram: Scottish Cafe Racer
BSA A7 500cc Alloy head, 55 engine 57 frame.
Print
Pages: [
1
]
Go Up
« previous
next »
The BSA A7-A10 Forum
»
Technical (Descriptive Topic Titles - Stay on Topic)
»
Amal, Carburation
»
A7 shooting star 376 mono carb setting no filter