Starting after rebuild
Posted: 13 Dec 2017 12:59
Hi,
I have just completed a complete bike and engine rebuild of a 501 New York and am having trouble getting it to idle and run nicely.
The bike has been put back to factory settings, so the idle jet, pilot and main are all as best as I can gather standard (thanks Morini NL website).
The air filter and air box are standard Morini with the exception of the removal of a couple of the more restricting pieces of plastic, flower pot type thing etc as suggested by NLM.
Dynamic timing has been done by strobe and seems spot on. Spark is healthy.
I am using clear fuel line for the moment, so I can see it has no fuel restriction and the Float bowls are filling.
The bike will reluctantly start only with a feathering of the throttle. It will continue to idle at around 4000rpm only with both chokes on.Or without choke only with throttle, if I can catch just the right amount, even when thoroughly warm.
It appears to run happiest with both the mixture screw and idle stop almost all the way in, although to be honest the effect of adjusting the mixture screw is minimal. Attempts when running to turn the idle down always result in a stall around 3500rpm.
The carbs were thoroughly cleaned and rebuilt with new Dellorto service kits, everything appears unblocked.
I am aware of the mod that can be done to the timing strip on the magneto and although not adverse to the idea I feel I must be able to at least get the bike running ok before trying to perfect it.
The good news is that occaisionally for brief periods when using just the correct amount of throttle, the bike runs smoothly and sounds lovely, so I am not despondent just struggling for ideas to move forward. Any thoughts very gratefully received.
Thanks, Mark
I have just completed a complete bike and engine rebuild of a 501 New York and am having trouble getting it to idle and run nicely.
The bike has been put back to factory settings, so the idle jet, pilot and main are all as best as I can gather standard (thanks Morini NL website).
The air filter and air box are standard Morini with the exception of the removal of a couple of the more restricting pieces of plastic, flower pot type thing etc as suggested by NLM.
Dynamic timing has been done by strobe and seems spot on. Spark is healthy.
I am using clear fuel line for the moment, so I can see it has no fuel restriction and the Float bowls are filling.
The bike will reluctantly start only with a feathering of the throttle. It will continue to idle at around 4000rpm only with both chokes on.Or without choke only with throttle, if I can catch just the right amount, even when thoroughly warm.
It appears to run happiest with both the mixture screw and idle stop almost all the way in, although to be honest the effect of adjusting the mixture screw is minimal. Attempts when running to turn the idle down always result in a stall around 3500rpm.
The carbs were thoroughly cleaned and rebuilt with new Dellorto service kits, everything appears unblocked.
I am aware of the mod that can be done to the timing strip on the magneto and although not adverse to the idea I feel I must be able to at least get the bike running ok before trying to perfect it.
The good news is that occaisionally for brief periods when using just the correct amount of throttle, the bike runs smoothly and sounds lovely, so I am not despondent just struggling for ideas to move forward. Any thoughts very gratefully received.
Thanks, Mark