rough running below 3500 advice needed

[dougie conacher]

Hi there
spent forever trying to get my nc30 running clean through the the full rev range,have now got it really good above 3500 but crap below that would it still be running on the mixture screws up to 3500,i have not had the vacum gauges on yet as i figured there was still something not right but set the butterflys with feeler gauges so there hopefully not that far out.the bike has a full tyga system ro needles and jets airways cleaned out local honda agent reckons even if you can blow air through they might still be partially blocked .done float heights,double checked jets are in the right places new carb rubbers and orings doesnt seem to be drawing in air, any ideas what to try next.
thanks in advance dougie.

[vfrman]

Float level...
http://www.factorypro.com/tech/tech_tun ... gines.html

[dougie conacher]

i made a big effort to get the float height at 6.8 when i enter a built up area where i have to drop the revs to 3000 its instant, the fluffy running, if the float level was out it would take a bit of time to show whether it was rich (which i suspect is the case) or weak the bike is clean all the way above 3500 anyway i will check again when take the carbs of again? at least am getting good at removing and replacing the carbs,so what revs does the primary circuit end.
dougie

[vfrman]

When cruising at low rpm and partial throttle, the fuel screw plays a role. If it is too rich, you can try leaning it out 1/2 turn at a time. I'd also balance the carbs, because this is low rpm/low throttle is where you will feel that the most.

[dougie conacher]

ok will try balancing them is it worth changing float height from 6.8 the exhaust gets a bit sooty if you keep it at low revs so its likely a bit rich
thanks dougie.

[vfrman]

One thing at a time. Try leaning the idle mixture by a half turn and see what that does.

[dougie conacher]

ok the saga so far,ended up striping the carbs again made sure everything was spotless and jets in the right place,all gallery s were clear for piece of mind if nothing else.Then i decided to try and balance them got them pretty close but not sounding great revved it up let it settle and the readings were different readjust carbs again different reading again,did this about 8 times every time different outcome now i presume that suggests an airleak at butterfly slides area,am now totally lost about what to try next apart from getting another set of carbs.just to recap on what i have done built one set of carbs out of two sets,new seals,manifold rubbers,rick o needles,122 back120 front,done float height and been very careful building the carbs,i have been running just the one throttle cable i should put the the return cable back on ,see if it helps shut the butterflys better but am probably just clutching at straws with that one.
cheers dougie.

[Neosophist]

did you put new carb rubbers on the bikehwne you did all this?

every set of vfr cabrs ive rebuilt have run almost perfect at stock steting.

it sounds like you have airleaks on rubbers / something isnt clean / set right.

[dougie conacher]

yes i did fit new rubbers i forgot to mention its got full tyga system hence the jet size sprayed the carbs with wd while it was running no change in how it ran is there any way to check the mixture at tickover on the seperate cylinders.