Author Topic: she wont rev out...  (Read 20361 times)

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Offline Johnniespeed

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Re: she wont rev out...
« Reply #15 on: August 16, 2009, 10:02:25 AM »
 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
Spring is here and the Mighty 500 wants to ride.
 2004 KX500 E16
 Michigan has the best groomed and mapped trail system, check out the Cycle Conservation Club of Michigan trail maps.

Offline fluffy

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Re: she wont rev out...
« Reply #16 on: August 16, 2009, 12:39:39 PM »
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.

Offline Grunty-Motor

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Re: she wont rev out...
« Reply #17 on: August 16, 2009, 06:26:41 PM »
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.

Offline Enduro Addict

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Re: she wont rev out...
« Reply #18 on: August 18, 2009, 04:38:30 AM »
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.

Offline kxracer

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Re: she wont rev out...
« Reply #19 on: August 18, 2009, 07:49:55 AM »
Try PJME in Wolverhampton, prices are good, service excellent. They also sell other spares.

Good luck

http://www.pjme.co.uk/

Offline Grunty-Motor

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Re: she wont rev out...
« Reply #20 on: August 23, 2009, 07:16:21 AM »
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?


Offline Hillclimb#42

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Re: she wont rev out...
« Reply #21 on: August 23, 2009, 08:20:51 AM »
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.

Offline serafin

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Re: she wont rev out...
« Reply #22 on: August 23, 2009, 10:33:15 AM »
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

Offline Grunty-Motor

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Re: she wont rev out...
« Reply #23 on: September 28, 2009, 08:15:39 AM »
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.

Offline kaw rider

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Re: she wont rev out...
« Reply #24 on: September 28, 2009, 09:10:13 AM »
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.

Offline fluffy

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Re: she wont rev out...
« Reply #25 on: September 28, 2009, 02:32:59 PM »
i think the float is sticking.

Offline Grunty-Motor

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Re: she wont rev out...
« Reply #26 on: September 28, 2009, 06:20:38 PM »
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?

Offline kaw rider

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Re: she wont rev out...
« Reply #27 on: September 29, 2009, 01:38:25 AM »
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.

Offline fluffy

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Re: she wont rev out...
« Reply #28 on: September 29, 2009, 11:52:37 AM »
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.

Offline Grunty-Motor

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Re: she wont rev out...
« Reply #29 on: September 30, 2009, 07:46:17 AM »
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.