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[taper]

Hi all finally I have made it back on the road ,all be it a test run,my 350 bullet starts ok but does give the occasionl spit back through the carb when starting,but when out on the not so open road
it sounds like there is a sound like compression is escaping , on halting the test run the sound of (chuffing) is coming from the air filter on ignition stroke I think,also some loss of power when accelerating,any ideas.

[Alan R]

-----Hi Matey !! It does seem like the inlet valve is leaking slightly under pressure (ignition stroke)...With the engine at running temp, check the tappets are set correctly--Take the air filter off,ignition turned off, throttle held wide open,----use the kick-starter to turn the engine over rapidly, listen at the inlet port. If you hear a substantial blowing (chuffing) or , placing your hand over the inlet port, you feel a blow-back or a back-pressure, then you have a leaking valve.....This will give poor starting, bad idling, some loss of power....Don't be afraid----It's a head-off and full overhaul. ( Valve grinding etc. )----and why not a set of fresh rings whilst you're at it ??

[taper]

Hi alan the valve setting on instalation were very tight, poor compresion
on trying to start,adjusted the valves and compresion returned,but have not checked the valve clearence since the test run,is it better to check the clearence when hot or cold,

[taper]

forgot to mention this engine was a replacement unit alegedly re built in india.was running ok or so the vendor told me.

[Alan R]

----------cold ideally with ZERO clearance, ie pushrods free to turn but no lift. Piston at TDC on compression stroke. A round-ended rod CAREFULLY down the plug hole will guide you to TDC approx. After setting---rotate the engine a few times and re-check.

[Norm]

A drink straw down the plughole I find is best, too long to fall in and doesn't matter if you move the piston too quickly.