'93 F2 if you didn't already know

so last monday or so it felt like it was losing power in just about all RPM's, but especially down lower, like 5-6k.

it sounded/felt like it wasn't firing on all 4 cylinders. so i changed the plugs with iridium plugs and the old plugs had a lot of black, oily deposits on them (all 4 equal, none worse than any other).

with the new plugs in it feels the same, so i guess it wasn't the plugs fault. worn piston rings?

maybe i should take the engine out, strip it down and rebuild it. that would be fun, but time consuming, and i won't have much free time the next 1.5months. can't afford to pay $75/hr for a professional, so i'd like to work on it myself.

 

that sucks dude, maybe has somthing to do with your intake (carby) or you could have had a bad tank or gas, check your fuel filter and maybe tune your carby, im not saying this is the problem just something for you to look at,

good luck

 

before you 'rebuild the engine', start at the cheapest end first. airfilter, drain the tank and put fresh gas in it, clean the carbs (there are write-ups online), check to see if you have hot sprark to each cylinder.

to run an engine must have 3 things:
Air/Fuel
Spark
Compression

Start at the top & work down. My guess is with the fuel system.

Edit: Check the obvious too, make sure your choke isnt on, and you do have the petc0ck set to ON w/gas in the tank.

 

D0od do a compression test first
next take a gas sample
then make sure ur generator is charging and the ballast (aka )resistor isnt going bad..
Always remember not to listn to any one that dont kno what they are talking about..
^^^^^^^^^ i had to throw that in..lol
Your compression test will tell you a lot,you can tell by ur plugs if u have water in gas..
(gas ) if carnerated --dry gas ok------( gas) if fuel injected ONLY use isoprohpyl ( if i spelled it right _
Let me know if u need any further help

 

AFter you changed the plugs did you try to start it when it was cold out? Like below 25F? If so you could have fouled the plugs again. Intake runners are so short on motorcyles the fuel doesn't have much or a chance to get to vapor in the colder climates so these things are prone to foul plugs when it's cold out. When you do get it started make sure you run a whole heat cycle threw the plugs before you shut it off. Until the fans comes on.

 

if your plugs are oily that makes me think it's valve guides/seals or rings. if you had a restriction in your fuel system your plugs would most likely be white/ashy. do the plugs smell like fuel? if so it's rich and i'd start at the air filter. rich conditions can cause black plugs.

 

a quick way to check if its running on all 4 cylinders is to let it run for a minute and then pour a few drops of water on each exhaust pipe 6in to a foot away from the motor. if it sizzles and evaporates right off the pipe then that cylinder is firing, if it doesnt then its not firing or not firing right.so then further investigate- is it not getting spark or fuel? a lot of times cylinders 1 & 3 and then 2 & 4 run off the same coil so if those pipes are not hot its most likely an ignition problem where if its just one cylinder not firing it might be carburation.

although thats not set in stone its a good start to figuring out whats going on. have you figured out anything yet?? post up and let us know so maybe we can get you running right again cause although its nice to have a freshly rebuilt motor, why go through all that and waste money(and time from riding)when most likely its not nessesary. just my , hope it helps

 

What up FreddySpence I live 20 mins to Woodstock. Anyway the bike needs coils or a regulator rectifier.

 

whats up vw- where do you live? woodstock is a cool town with a lot of history for sure. i just came back up to the adirondack mtns last week ,but i went to school in saugerties and lived in the woodstock area for a long time.

we'll have to go riding when it gets a little nicer- go tear sht up

 

thanks for all the suggestions. i'm really busy this week and won't have a chance to look at it until saturday, but i'll let you know how it goes.

 

mine did that for 2 months or so then it just fixed itself and ran strong as hell

 

Yeah I went to Kingston High. Would like to ride with some local stunters
Also Me and a good friend have a phat garage if you know anyone who needs some work or some custom **** done.

 

that happened to me too on my gsx-r1100 sometimes it runs powerfull as hell and sometimes with about 60% of its power i think its a carburator problem but it happens randomly

 

WHAAAT!?!? You can't say that what it needs. No way can you tell from what was said that for sure that's what's wrong.

 

k so i rebuilt the carbs and they were really gummed up inside.

turns out i wasn't getting any spark in #3 so went through and checked electrical system. turns out i my ignition coils are way below spec so i have 2 new coils on the way and that should fix it. gotta wait til end of the week to get them damnit.

 

wow he was pretty damn close to the problem haha

 

one thing to make sure when you put the new coils in is to make sure all the connections are clean and tight.. also, if the coils bolt to the frame make sure the frame is clean so they ground to the frame well-- i usually take a piece of sandpaper and clean the frame so its free of corrosion.... just my good luck and yeah like tom petty said- the waiting is the hardest part

 

ok so i rebuilt the carbs and got the new coils on. started right up but #2 and #3 headers weren't getting hot. i was like WTF? so i pulled the plugs to make sure they're getting spark. yeah, getting spark. WTF? checked secondary coil resistence and it's 23.5 (spec is 21-25) so that's good. so i took it for a highway spin for about 20 minutes to see if things would just sort of 'fall into place' so to speak.

so it pulls hard towards to top end, but seems to bog down and hesitate down at the low end. i had no trouble getting up to 135mph fast, but when i'd start to slow down it would hesitate at lower rpms.

when i got home i felt the headers and they were all too hot to touch so all 4 cylinders seem to be firing at higher rpms.

WTF?

 

all those headers would be hot after running it for that long weather 1or 2 were firing or not but it really sounds like a carb problem to me at this point-- ive seen floats stick and ive seen jets that werent completely clean make a bike run like chit- did you clean every little hole and crevice in the jets,bowl and passageway in the carb?? ive seen carbs done at a shop where they werent done right let alone backyard mechanics trying to save a buck so go through the suspect carbs again if you have to.... are those carbs getting fuel? is the float full of gas or not closing the valve so maybe at low throttle its running too rich to even fire but at high speeds where its using more gas it cleans out and starts firing??

theres a lot of possibilities but id take a look at those carbs again- and pay very close attention to every little detail ... good luck