avenger Posted May 2, 2006 Posted May 2, 2006 I just bought this 1987 fz600 from a friend for 300 bucks, but now im having problems with getting it running right, it was stored in a garage for like 6 to 9 months before i got it. i got a new battery for it and new plugs and wires, flushed the tank and put premium in it. it started up and ran good, than i took it for a ride and it wont go any higher than like 6-7k its like it has a fuel cut and just bogs down. so im wondering if its the carbs that need rebuilt or what i cleaned them and no luck after that. any help would be appreciated jesse
Moderator YamaHead Posted May 3, 2006 Moderator Posted May 3, 2006 to the forum Jesse Sounds like you've definitely got issue's with those carbs still Did you clean 'em yourself?.......If so, Did you remove & clean each Main, & Pilot Jet individualy? It might also be the Air Jets in the top of the carbs...under the slide diaphram. If you get all those cleaned & reinstalled properly.....& the floats didn't get bent in the slightest way.... It should run like it's supposed to! PM me if you'd like me to steer ya through it.....pretty familiar with these carbs......as they're very similar to the carbs on my old Seca550.
Moderator YamaHead Posted May 3, 2006 Moderator Posted May 3, 2006 I got your PM, & thought it might help explaining things a bit with this pic I dug up..... 1st put the carbs into a vise with the fuel bowls facing upward......then systematically remove all 4 bowls, keeping them in the same order, along with the jets, floats etc......for easier reassembly. The items you want to make sure are really clean..... that are in the Fuel bowl section are: Main Jet Pilot Jet Float valve assembly......this can be removed by tapping the float pin out 1 side of the pivot mount with something thin & long like a pick or even a small nail. Once that pin is removed, the float will come right out with the valve seat semi-attached...(valve seat is part of the float valve assembly & you need to make sure it doesn't have a ridge worn into the rubber cone tip on the end of it...or else it won't shut the fuel off properly causing it to flood out. Be careful NOT to bend the Floats in any way as this will mess up your float levels The Main jet is the biggest & easiest to remove & clean.....the Pilot jet requires a rather small standard screwdriver to remove....making sure this small jet is clean will ensure your idling circuits are working correctly.....also it's a likely culprit of running poorly especially after a bike has sat for awhile. This same type of proceedure can then be applied to the tops of the carbs....exposing the slides, needles & Pilot Air jets which all need to be sprayed clean with carb cleaner. Before reassembly, make sure & spray clean all the orifices in the carb bodies themselves. Then begin reassembly in reverse order starting with the tops......also making sure there's no tears in the diaphrams around the slides & the needles are good & clean. Then flip the carbs once again to reassemble the fuel bowls......(If you keep all the parts layed out on the bench in an orderly fashion, it makes things a Whole lot easier when you get to this point ) Once you get the carbs reinstalled in the bike, turn your fuel petcock to the PRI position for about 10 seconds.....to allow the fuel bowls to fill up. Then turn back to the ON position & with full choke, hit the starter! Hopefully this'll eliminate your previous running problems. Hope this all Helps-- Let us know how make out with it
harry69koi Posted May 3, 2006 Posted May 3, 2006 Might sound daft but are you sure the bike isnt restricted? Here in the uk peeps have them restricted to 33bhp if they took the A1 type licence? just a thought?
Moderator YamaHead Posted May 4, 2006 Moderator Posted May 4, 2006 Don't think that's the case here Harry No restriction issues here in the states
avenger Posted May 4, 2006 Author Posted May 4, 2006 so i did everything that it said to do in the intructions above and it idles like a champ and there is definitly a gain in power but it still cuts at like 6500 or so, not as bad but still there, would maybe getting the carbs synchronized help any or getting the valves shimmed?????
Moderator YamaHead Posted May 4, 2006 Moderator Posted May 4, 2006 Could very well be that the carbs are outta sync now Can't remember if the FZ600 had the YICS head or not.......it should say YICS down on the small crankcase cover on each side......I don't think it does? A special tool is required for syncing the carbs on those YICS motors......one that I'm told is not available anymore!....(Half the reason I sold my Seca550) I think the best plan of action @ this point would be to shim the valves AND synch the carbs....& see what kind of results that leaves you with.
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