Honda-SOHC

SOHC.co.uk Forums => CB350/400 => Topic started by: Multiman on February 17, 2023, 06:51:59 PM

Title: Spark timing advance unit
Post by: Multiman on February 17, 2023, 06:51:59 PM

Hi all
I've inspected the spark advance unit and noticed that the springs have seen better days.
Obviously this will affect the advance in some way, so the question is can they be replaced and if so where from?

Second question is the plugs are very sooty.
Should I be adjusting the air screw, they are set to 1.5 turns.
Which way to lean the mixture or should I be looking elsewhere?

Many thanks in advance and sorry for the constant stream of questions right now!
The help is much appreciated

Title: Re: Spark timing advance unit
Post by: Bryanj on February 17, 2023, 07:07:32 PM

Springs are not available seperately but it is reported on the us site that removing 1/2 turn and reforming the loop works, never tried it myself just passing on what ive read

Title: Re: Spark timing advance unit
Post by: Nurse Julie on February 17, 2023, 07:25:48 PM

Turn screw out for more air, turn it in for more fuel.

Title: Re: Spark timing advance unit
Post by: Multiman on February 17, 2023, 07:32:49 PM

Thanks both for getting back to me.
More to experiment with.
Cheers
Tim

Title: Re: Spark timing advance unit
Post by: K2-K6 on February 17, 2023, 07:35:15 PM

There's ordinarily a good routine in Honda's manuals about setting the slow speed mixture with the screws. Very worthwhile in understanding how to optimise them.