having trouble tuning bike cleaned carbies 3 times, set float levels to 10.5mm, set idel screws to 2.75 turns out form full in, syned carbies, checked exup, set valve clearances, checked spark gap, cleaned air filter, ensured air box is on secure. it rides ok up and over 11000 but from 9000 - 11000 it really bogs down. it bogs down under full twist but if i back it off a bit it runs better. i still think the bikes running rich cuz it isn't that hard to flood and only gets 10l/100k <!-- s:-? --><img src="{SMILIES_PATH}/icon_Eyecrazy.gif" alt=":-?" title="Eye Crazy" /><!-- s:-? --> (my v6 3l car does this on the highway). also it blows a little black smoke when revving it out. and the plugs are a little black. also the idel is either 3000 or 1000 and no inbetween. would like for someone in north brisbane to come over and help me tune it up and i will return the favour some how. <!-- s:cheers: --><img src="{SMILIES_PATH}/th_Cheers.gif" alt=":cheers:" title="cheers" /><!-- s:cheers: -->
Do a rectifier check; a VR going south does bad things to the black box which makes the bike run poorly. Also, check and adjust your EXUP.
yeah already done a reg/rec check fine and iim pritty sure that the exup is working fine. im just trying to get hold of a compression tesster that has a small enough fitting for these tiny spark plug holes.
You've cleaned and secured the air filter and airbox - is the inlet snorkel fouled / plugged? Leaves, socks, small animals... Also, check your float needles - some old ones had brass tips vs the newer viton, and could hammer in over time and no longer seal. Check the o-rings on the float needle seats, too - that went off on my race bike, and I had to close the petcock IMMEDIATELY every time I came in, or else it'd flood terribly.
Has this been like this since you have had the bike, or has it been ok and then got worse over time??? It really looks like a jetting/carb issue. What model bike do you have??
dontz125. i have checked the float heights with the pump on on the carbie stand and adjusted(very long process took all day and then some). the neddle has a black rubber lookin tip and the seat is just the creamy coloured plastic surrounding it. also i have run the bike with out the air fillter around the block(no differance) but the air box is is in very good nick. wired th exup open and only small differance down low. dave. it used to do it not so bad before it sat still for about a year but before i rode it it got a compleate overhaul. (new chain and sprockets, new powdercoated frame, cleaned fule tank, cleaned carbies, valve clearance, forks got a rebuild, head bearing was redone, oil changed twice, new oil fillter, cleaned sump and oil window, new brake fluid, rebuilt front master cylinder for brakes, cleaned exhaust, new blinkers.) But now it's worse and making riding no fun at all. im pritty sure that it's in the carbs but am going to check the compression before i continue any more. a message for anyone thinking of doing some work on there bike instead of sending it to a mech. This overhaul was done with infomation gathered from this site and the 250 and 400 manuals prittty much by myself and with time and paitaince and a little understanding it can be done. just dont put something back together without fully understanding how everylittle bit of it works. the only thing i have trouble with is i cant tell the differance between rich and lean as much as a cow and a duck
When you stripped and cleaned the carbs, did you pop the clips off the jet needles? Where are the clips set now?
Just try moving the clips on the needles up one position and see ifit gets better or worse. Other thought <!-- s:finger: --><img src="{SMILIES_PATH}/icon_idea.gif" alt=":finger:" title="Finger" /><!-- s:finger: --> You have had the camshafts out. It is extremely easy to put the shafts in one tooth out of position and still look like it is nearly right.
heres a great trick for checking carb synch my mechanic friend showed me ... you need a hairspray bottle or water pistol etc - something that will shoot a stream of water. start the bike from cold and get it on idle (choke on or of is fine - but better if rev are up a bit) then put a quick blast of water across your headers - the water should evaporate off quite quickly (2 or 3 seconds) what you want to see is if it evaporates reasonably evenly across the four headers... if one or more take allot longer to evaporate then that cylinder is running rich (running rich will make it run a little cooler than the others hence the difference). I had a very similair problem with my bike - this identified the one pot that was running rich (i was also getting about 10 l per 100 km) at it turned out to be a worn needle.
ok moved the clips to position 1(furtherest away form pointey end) and the bike runs heaps better. the problem with the bike bogging down from 9-11 is still there. also i haven't got to go through a full tank yet but im pritty sure my fule consumption is much better. but will find out soon. does anyone in brisbane want to have a ride and tell me what they think i need to do to it.
