Have early type CD175's with adjustable main jets at the bottom of the float bowls.
Currently using new needle/seats and new 100 main jets with new H2 needles, revs out well, but cannot get engine to nice low idle...OK at 1200rpm...running rich when at about 700rpm....cannot get any further mixture adjustment for nice low idle. Tried altering the fixed position of the needle a bit lower..no difference.
There are no apparent air leaks.... carbs are not flooding.
Should not be the needle size as all needles will have the same idle profile within 0.0001".
The only thing that I can think of is that the carb is over fuelling at idle. The float level has been set at what the manual says ie. 0.73" or 18.5mm.
Adjust float level so that the needle/seat closes earlier?
What is the correct main jet and metering needle size?
Comments appreciated...please do not suggest changing to SU's.
Currently using new needle/seats and new 100 main jets with new H2 needles, revs out well, but cannot get engine to nice low idle...OK at 1200rpm...running rich when at about 700rpm....cannot get any further mixture adjustment for nice low idle. Tried altering the fixed position of the needle a bit lower..no difference.
There are no apparent air leaks.... carbs are not flooding.
Should not be the needle size as all needles will have the same idle profile within 0.0001".
The only thing that I can think of is that the carb is over fuelling at idle. The float level has been set at what the manual says ie. 0.73" or 18.5mm.
Adjust float level so that the needle/seat closes earlier?
What is the correct main jet and metering needle size?
Comments appreciated...please do not suggest changing to SU's.