KX Riders
Maintenance & Technical => KX500 Original => Topic started by: Grunty-Motor on July 14, 2009, 09:18:51 AM
-
Need a bit of help from you guys. finally had the chance to take out my recent purchase (89 500) and after warming up, i gave it some stick - but it gets about 1/2 way through the rev range and starts stuttering. doesnt feel electrical - more fuel. seems to have plenty of power down low and will lift in 1st/2nd.
it wont rev out in any gear. Some background;
mains - 170
second - 58
needle - middle
air - 1.5 turns out
double base gasket fitted (previous owner wanted it easier to start)
FMF fatty pipe
Tried setting float height - could understand my Clymer manual - the picture shows the point at the needle valve closing - but where do i measure?
checked the timing marks and they are at the edge of the 3 allowed marks
KIPS valves are free to move (took the little plastic cover off and it moves in and out)
standard ngk plug - brand new - so no colouring yet
reeds are fine
nothing in trans. oil
air filter clean
i'm at sea level and temp is 15-20deg.
she starts fine and idles perfect.
it really feels like there is not enough fuel - but even with a wrongly set float, wouldnt it rev out in atleast 1st?
anyone got any ideas?
-
it really feels like there is not enough fuel - but even with a wrongly set float, wouldnt it rev out in atleast 1st?
anyone got any ideas?
Gear selection has no impact on the float bowl, or otherwise how much fuel your motor is consuming. All the carb knows is air velocity. Sounds to me like you might have more problems than you think? It should loft the front end quite easily in 3rd and 4th as well.
It sounds to me like the reeds have hairline cracks. I know you said they were good, but be sure to inspect them with a fine tooth comb and magnifying glass (figure of speech). Also try a leak down compression test. It sounds to me like you're down on power everywhere. My '89 lost it's electrofusion plating and caused all kinds of problems. If you catch it early it could be as transparent as a top end rebuild and replating in your case. Aside from that go with your instincts. If you think it's lean richen it up...see what happens. Your jetting sounds in the ballpark by my recolection.
-
this is my first 500, so i dont have much of a bench mark - but there seems plenty power low down. it just wont rev out.
looking up the exhaust port seems to suggest piston/barrel ok (from the little i see).
reeds looked new - will have a closer look though.
anyone know the size for the flywheel puller? (or a UK Supplier)
-
can someone confirm - flywheel puller = M27x1 - left hand thread?
-
If flywheel is made by denso im sure its m27x1 lefthanded thread. Anyways its the most common thread for flywheels. Nearly every bike from pitbikes to kx500 uses the same puller.
-J
-
Sounds similar to how mine ran when I was running too much oil in the premix. I started running at 40:1 and all my problems went away. It took a while though. Had to just hold it WOT for about a mile before it cleared out. Its worth a shot, since it's about the easiest thing to try.
http://www.kxriders.com/forums/index.php/topic,5754.msg44027.html#msg44027
-
too much oil? that sounds plausible - it is kicking out goo at the exhaust/silencer connection - and its only been running about 15mins!!!
think i am a little richer than 40:1 as that is what my RM250 is on. i'll try 50:1 and go canny on the throttle and see if it cleans out then drop it back to 40:1.
-
last request (for the moment....)
where do i measure the float height - manual says 15-17mm but the picture aint that clear.
-
There you go! http://www.allthingsmoto.com/forums/f-15/how-set-your-motorcycle-carburetor-float-level-more-commentary-13608/
By the way did you happen to change to ATF type F or similiar from normal 10w30 or 10w40? :mrgreen:
-J
-
hello grunty motor!
well it seems we are in the same boat :?
i just got a 1994 kx500 a few days ago and it will not rev out, lots of low end. as for the mixture, i'm running 40 to 1 like the last owner, same proplem... my bike sat for 4 years in a barn when i bough it. it started after 4 kiks, and idle fine. the two problems i have is the last 70% of the rev and after opening it wide open it will do this funny thing where it is like the trotlle comes on and off by little sharp sequence and eventually stop and idle fine.
so far i have check and clean carb, float... everything is fine... timing look ok even to the clymer manuel is not so clear about it. spark plug is new and gap ajusted...
so what are the reeds your talking about? and how do you check the intake valve and exhaust?
maybe between the two of us will get them to go like they should, stupid fast... :-D
it is my first 2 stoker, so all new to this.
-
There you go! http://www.allthingsmoto.com/forums/f-15/how-set-your-motorcycle-carburetor-float-level-more-commentary-13608/
By the way did you happen to change to ATF type F or similiar from normal 10w30 or 10w40? :mrgreen:
-J
cheers J - my floats are sitting too low. hope thats the issue.
And, yes, i am running 50/50 ATF & 10/40 - why you ask?
-
Im just asking because i had same thing a few week ago. In my case the viscosity of the ATF type F oil was so big it came through the smallest imperfections into crankcase. I re-surfaced my crankcases and problem solved! I thought it was the crank wet seal that was leaking but it wasn't the issue. Previous owner used normal motoroil in the tranny. Its a lot "thicker" than ATF F.
Adjust your float level and post us some info how it runs. Try switching normal 10/40 if float level doenst make it run any better.
-J
-
well well,
i found my problem...
my exhaust valves are so for of carbon, nothing is moving ... so i decoded to do a complete buttom and top rebuild. this way i start fresh. and i also think it is the cheapess way to go long term.
i already took the engine out, everything look very good, no bad surprises...
so hope you find your problem soon. :-D
-
good to hear - it might be a bit of work, but atleast you know the cause.
-
bit of an update (been struggling for time.....)
1. float bowl set proper = no difference
2. new carb slide (old one has ridges in it but i thought it was ok) = no difference
3. changed tranny oil back from ATF to 10/40 = no difference
4. fitted coil from my ktm - it now revs cleaner, but there is no real power there
PLUS,
coolant coming out of overflow = weak rad cap or head gasket probs?
plug is a bit oily - maybe its cause its been running crap for weeks?
its surging on the over run
next step is to get a kx coil and i'll run it a bit longer incase it needs clearing out (clutching at straws me thinks)
-
I read on a different thread of someone having a partially clogged silencer, they cleaned and repacked it and power was restored.
I have also heard of others having a partially fouled plug and that causing problems.
The silencer can be taken apart on my bike, so this experiment would only involve time and not money, if you are grabbing at straws, perhaps you could have a look inside the silencer.
I had a red bike that only ran great when the transmission was empty and wouldnt rev up when the transmission was full, turned out to be a crank seal on the clutch side.
None of my statements are meant to be a diagnosis but rather some ideas to think about.
Hope you figure it out soon, keep us posted.
John
-
make sure you warm that thing up. sometime it takes me 5 or 6 minutes before i can really give it the gas. cold seize i think its called.
-
thanks for replies.
silencer is brand new and deffo not that.
have ordered a new plug and cap (just in case)
I am leaning towards the crank seals (was doing some more reading on it last night) - i just dont have anything to do a leak down test. might try running it with say 1/2 the tranny oil and see how it goes.
the more i think about the coil, the more i think its just giving it a stronger sparrk and masking the real issue.
-
I would also check to make sure the KIPS was installed correctly. You can put the right in the left and vice versa. I know, because I have done it. It had decent bottom, but would not rev out.
-
Try PJME in Wolverhampton, prices are good, service excellent. They also sell other spares.
Good luck
http://www.pjme.co.uk/
-
i am trying desperatly not to have another motor in bits (until the middle of winter at the least...) but if i do, i'll check the KIPS properly - cheers.
put the old coil back in and drained 1/2 the gearbox oil out. new HT lead, plug and plug cap. its missfiring worse. so, maybe the coil aint that good (meets the specs of the manual though).
did a compression test - 140psi (bearing in mind it has bouble base gasket fitted). so that would seem to be ok.
next chance is to fit a new coil and heavier (mineral) oil rather than the semi thats in it now.
any thoughts on why it might surge on the over run?
-
My 500 quit surging when I got the idle screw backed out to a useable position. When I bought the bike it was worn-out and the throttle cable was tightened in the adjusters to get it to idle. I didn't know that right away, but I did notice that the idle adjustment did nothing. That was because the seals were worn and so was the cylinder. The slide slamming closed completely is what you want for less surging. Jetting can get you to idle as long as the seals are tight.
Also, the surging will only get you into trouble, if you forget to grab the clutch.
On another note, I recently discovered that floats set too high(to shut-off the gas later) robs lots of power and causes a rich condition that is impossible to jet- out completely. Getting the floats set perfect, and being absolutely positive the reeds are sealed ( resisiting raw fuel) makes it rev hard. A few times we have tinkered on the jetting or float level and actually somehow caused the floats to stick or not get it back right. Keep an eye on overflows when having these issues. Fuel pouring out is a stuck float which is easily fixed. Make sure the flow of air is as free as possible, i.e clean filter, clean functioning powervalves, clear silencer.
-
To me it sounds like your problem may be an electrical issue. Not really knowing the history of the bike (how many owners/rebuilds ect..) and it being a 20 year old bike. The electrical components have probably broke down. The coils may test ok but may actually be bad. I would consider replacing the stator coil.
Serafin
-
a little update - havent had much time of late...
bought a new coil - it now revs out, but no power.
put 20-50oil and only half filled it - made no difference [that was to see if it was drawingoil through the crank seals]
pic of the plug attached - brand new, done about 10miles. running a pre-mix of 45:1.
does it look like its drawing tranny oil?
next step is to get a flywheel puller and check the stator.
-
get a new spark plug and set the gap at .250" & .375" and see if it jumps the big gap.
Sounds like maybe a carb issue.
-
i think the float is sticking.
-
get a new spark plug and set the gap at .250" & .375" and see if it jumps the big gap.
will that not just prove that the coil is ok (which i know it is cause its new)
i think the float is sticking.
you mean its not falling down far enough and its not flowing enough fuel to fill the bowl at full throttle? could be, but why would fitting a new coil improve things?
it moves freely with the bowl off - how can i check it in situ?
-
I had a flywheel going south on me and installed a new spare flywheel and the spark got alot better. At that time i had a problem with motor down on power and it wasn't the ignition.
-
my 89 ran fine in 1 2 3 gear,in 4 when i gassed it all it did was bog down and blubber. i rode it into the garage and took the carb off starting with the top. i held the carb as level as i could so no gas would spill out. i loosined the screws holding the bowl on and when i broke the seal i had gas pour out. the bowl was filled to the top. i put the bowl aside held the float up with my finger and let it fall. i did this half a dozen times 2 times it didnt come down. check the rod in the needle valve, push in and make sure it comes out. check the rubber tip for a groove.replace if any question. good luck.buy a good repair manual. alot in there.
-
cheers - i never checked the bowl for overfilling but i have had a good inspection of te floats and the needle/spring when i set the float level. everything was good. wont do anyharm to double check though.
-
today i checked the stator coils. timing was spot on.
ohm readings were
black/white to black yellow = 1500 [spec 153-230]
white / red to black yellow = 9.8 [spec 7.9 -11.9]
so, one of the cricuits is reading way out - any thoughts????
-
So, did you ever get it figured out?
-
So, did you ever get it figured out?
Dude, this post was dated Oct of 2009, i'm sure Grunty is long gone....
-
So, did you ever get it figured out?
Dude, this post was dated Oct of 2009, i'm sure Grunty is long gone....
Thanks....Dude.
I'd still like to see/hear his, or somebody else's, answer to this problem.
-
Probably float/fuel level buy a spare bottom carb plug, drill a hole in the center of it. Install a liquid nipple with o-ring on it with nut on the inside of the nut. screw the new plug in place, in the carb. now connect clear rubber hose to nipple and fill carb with gas from gas tank. run the hose up verticle and check the fuel level. its a very accurite way to check fuel level in the bowl.
-
believe it or not......I am still here
finally got back to working on this bike. had the crank cases split and fixed a dislodged circlip in the gear box (that was why it was engaging a gear when otherwise in neutral and leaning to the left). Crank seals and mains replaced but they were in pretty good nick so my problem isnt them.
While i await gaskets for the re-build i checked the stator again. It appears i have a '99 stator on my 98 bike due to the colour of the wires. but now, there is no reading black/white to black yellow. So i am thinking that the stator winding was on the way out and has now finally failed. Now i just need to try and find one in the UK
Can anyone confirm that this is a 1990 Stator?
How do i check the CDI is correct (other than the wire colours match?)
(http://i1192.photobucket.com/albums/aa338/grunty-motor/P1070297r_zpsc87ba1af.jpg) (http://s1192.photobucket.com/user/grunty-motor/media/P1070297r_zpsc87ba1af.jpg.html)
-
What bike is the stator suppose to be for?
Originally this topic was for a 89 kx500.
That stator does not appear to be a kx500 from 86-04.
-
hi, from the engine number, my bike is an 1989 model, E1.
but looking at the Clymer manual, the colour coding for the wires does not match the 89 model. It does match the 1990 model.
black/white & black/yellow & white/red
**** OOOPS - i noticed in my last post i say 98 and 99 - i meant 89 and 90!!! ****
-
After endless searching i am even more confused than when i started!!! What i think i have found is......
Very early (86 and below) have 6wires from the CDI and one is white / green
Middle 87-91 had 5wires and no white/green (but some had 1 coil and some had 2)
Late 91 on had 5wires and no white/green but different size flywheel
This is a link for an early one
http://www.ebay.com/itm/New-OEM-Replacement-Stator-Kawasaki-KX125-87-88-KX250-83-88-KX500-86-89-ESC1151-/291005593567?pt=Motorcycles_Parts_Accessories&hash=item43c148f7df&vxp=mtr
this is a link for a 89-91 version but has 4 wires to the plate and mine only has 3 wires!!!
http://www.ebay.com/itm/1989-1991-KAWASAKI-KX500-KX-500-STATOR-GENERATOR-ALTENATOR-MOTOR-ENGINE-/390531262696?pt=Motorcycles_Parts_Accessories&hash=item5aed7a28e8&vxp=mtr
They both look the same so may be an e-bay mistake - Plus, there is no pick up on the plate???
Still no idea what i have.....Grrrrr
-
The older Stators and flywheels were smaller than the newer units, just from memory I would say the newer is close to 5" and the older is like 4" in diameter
older stators 88 and older had 4 wires from the stator: black/red, white/green, white/red, and black/yellow
newer stators 89 and newer had 3 wires: white/red, black/yellow, and black/white
-
After phoning a few companies I found a place that knew a fair bit about the 500s - one of the guys had one himself so off it went to get re-wound.
turns out that one of the coils was a lighting coil and not wired up. That's why it dint look like any others i had seen.
anyway, re-wound and now ready for the re-build......
(http://i1192.photobucket.com/albums/aa338/grunty-motor/P1070298_zps86ad2bbc.jpg) (http://s1192.photobucket.com/user/grunty-motor/media/P1070298_zps86ad2bbc.jpg.html)