Damian,
Do you own any kind of repair manual for the TR6? If so, refer to the
section on carbs. If not, get one before you do anything else. A good
starting point for adjustment is to remove the piston and, using the carb
adjusting tool or an allen wrench, screw the needle up to where the brass
*head* is flush with the bottom of the piston. Exercise great care when
replacing the rubber diaphragm to insure that the lip and tab fit into
the groove and indention in the carb body.As a matter of fact, this is a
great time to inspect your diaphragms for pinhole leaks or tears. A small
air leak here can cause great problems as the vacuum needed to raise the
piston (and needle) will not be available and give the desired mixture.
Haynes has a manual devoted to the ZS carburetor that I have found very
useful. It describes the theory of the constant depression (CD)
carburetor in fairly simple terms, which when understood makes tuning and
rebuilding much easier.
Good Luck,
Jim Davis
Fortson, GA
'75 TR6 CF38690UO
'75 TR6 CF37325U
On Fri, 16 May 1997 10:21:09 -0700 Damian Penney <dpenney@fortpt.com>
writes:
>Hi,
>how do you adjust the mixture correctly on a pair of twin ZS carbs.
>When
>I used to have the choke out it would idle at ~2000rpm but performance
>would be great, so I guessed I needed a richer mixture. I played about
>with the mixture adjustment screws to little avail, I couldn't seem to
>get it to the point where revs would rise when I lifted the piston,
>every time I tried the engine coughed, spluttered and almost died.
>Somebody told me that the Gunsons color-tune doesn't work with our
>re-formulated gas, is this true ?
>
>So what I need is a nice step by step guide to tuning ZS', thanks a
>lot.
>I messed around a bit and now it seems to be missing, the engine note
>is
>more of a put put now, I adjusted the carbs and altered the timing.
>Help
>:)
>
>Damian Penney
>Developer
>Fort Point Partners
>
>612 Howard Street, Suite 300
>San Francisco, CA 94105
>http://www.fortpt.com
>
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