Forum

[Gwilly]

As per Tim, If your turning mixture screw out by more than two turns then your too big on the pilot jet..

There are a couple of other details worth looking at and that is the high level exhaust with baffle, which may not be as free flowing as imagined especially if the baffle is the non adjustable metal tube mute type..

If its the one with the adjustable tangs then reposition as experiment, back pressure may make a difference..

Cone and pancake filters can be troublesome with some more free flowing than others even with the same make and model.

Over jet the pilot thinking the pancake is flowing well and not restricting when in fact air flow is crap at tickover and 1/8 throttle only to pick up at half throttle and above..

Remember the intake trumpets that where fitted to Amals back in the day, Free flow is free flow, yes?

Wrong.. It was found that altering the length of the trumpet could have a profound effect on power delivery i.e. mid range torque or flat out "umph", (tech term)
So it can be tedious tuning a carb for performance across the scale with other items like filters and exhausts either helping or hindering your endeavours..

[geoffro]

Klutz, if you get no response from your idle adjuster the trick is to increase the revs to a fastish tickover and then try your adjustment, guarantee you will hear the change as you turn the screw.

[Reg]

I too have done just about everything to get a nice reliable tickover. Followed Mr. H's technical notes to the letter, and still I sit at the lights blipping away. Now, having read geoffros' advice re: raising the tickover speed I wonder if I raise this enough while attempting an adjustment. Like Klutz, altering the pilot air screw makes very little difference on my bike. Perhaps I should try substantially speeding up the idle.

[geoffro]

Forgot to say Reg that when you have a nice idle slow it down until it's perfect .

[simon]

Not sure what ignition the 65 has but stalling like that can be a sign of a failing condenser

[klutz]

Finally managed to replace the pilot jet with a 27.5 and go for a ride. It's early days but the tickover seems a lot more reliable as does pick up from idle.
Many thanks for all the suggestions and an internet beer for those who said fit a smaller pilot jet
Klutz

[ChrisD]

Hi, as Tim says above (and others) the pilot jet must be no larger than 30. My 1996 535 used to keep stalling until I opened the 32mm concentric carb and found that my old eyes had misread a 50 jet for 30. Once the correct 30 was in, all was better. In fact I’ll change the 30 for a 25 for more improvement soon.
Another reason for stalling at the robot (that’s a traffic light for you Brits) is if the clutch is binding. That’s the worst because it won’t go out of gear so you have to hold clutch and decompressor levers in order to push to the roadside to find neutral and then restart!
Cheers, ChrisD

[Creaky45]

Klutz and Scotty, You mention timing with a strobe. I am interested as to how you did it. I tried by removing the chaincase cover and marking TDC, 8 and 32 degrees on the rotor, then trying to put the piston at exactly TDC and making an index mark against the TDC mark on the rotor. Is this what you do? I find it almost impossible to put the motor in the exact position and also as the rotor is only a few inches in diameter the marks are very close. The only value in my method is to check that the timing is advancing to the correct amount. I still have to use the static method of 8mm using Mr H's cam locking tool. To measure .8mm BTDC is impossible unless the head is off.

[papasmurf]

Creaky45 use a Vernier caliper depth gauge through the spark plug hole. Or our hosts TDC finder.

[klutz]

Creaky. I did pretty much what you describe trying to be as accurate as possible. This includes forking out for the Dial Gauge with Plug Adaptor from Hitchcocks to find TDC