What should the motor sound like?

[oic0]

Im pretty sure I still have good compression (though I am about to checkz) since the kick lever is a bear, but I can definetly hear the motor as loud as an air cooled bike.

BTW, got to open it up on a country road. Goes like a rocket ship but wont power wheelie in third. May be this dented head pipe though. Front end waggle made me too nervous to go past 3rd.

[KX500freak]

Im pretty sure I still have good compression (though I am about to checkz) since the kick lever is a bear, but I can definetly hear the motor as loud as an air cooled bike.

BTW, got to open it up on a country road. Goes like a rocket ship but wont power wheelie in third. May be this dented head pipe though. Front end waggle made me too nervous to go past 3rd.

maybe lower the forks an inch in the clamps ,it will minimize speedwobble .
for the sound ,maybe time to tear top end down ,im up to the same issue as you on my streetk5
im thinking the pistonrings are worn on my bike

[oic0]

according to the previous owner the piston is 6 months since that was when he bought it and he payed the owner before him extra to put in a fresh 1 over wiseco. I wouldnt say it was that odd on an air cooled bike. The rd350 sounds like a type writer (edit* sewing machine is a better example), but I figured the water jacket should make these quiet. No idea of the ring life on these thing but cheap peace of mind is always a good thing I guess. I would really like to see if the crank is tight too while i'm in there since the previous owner had no idea what I meant when I asked about that.

[oic0]

Here we go, sounds about like this guys bike (except with a lot more ring a ding, think i need to repack the muffler lol)

http://www.youtube.com/watch?v=rDBERY0rbUw

[KX500freak]

lol that is the k5 from one of our members
crank tight,you mean bigend noise or how the crank fits in the cases ?

[oic0]

crank tight,you mean bigend noise or how the crank fits in the cases ?

No play in the big end. I usually wiggle and tug on the rod (boy that sounds wrong) whenever I replace a piston to make sure it has no play. I asked the seller about that but he had no clue since he didn't do the rebuild. He also didn't know what size over it was they had to use, only that it was bigger than stock.

P.S. Which member filmed himself in his pajamas lol?

[KX500freak]

crank tight,you mean bigend noise or how the crank fits in the cases ?

No play in the big end. I usually wiggle and tug on the rod (boy that sounds wrong) whenever I replace a piston to make sure it has no play. I asked the seller about that but he had no clue since he didn't do the rebuild. He also didn't know what size over it was they had to use, only that it was bigger than stock.

P.S. Which member filmed himself in his pajamas lol?

that is blown8950  http://www.kxriders.com/forums/index.php/topic,5512.0.html

[oic0]

I still can't decide if I have piston slap or not. Through the exhaust, the bore and piston look good but I can hear the piston moving pretty loudly. I get all worked up and want to rebuild it (then think of the 200-400 dollar cost, arg!). I watch some videos on youtube and most of the motors in those videos have the same sound. Then I think "I will just pop the top and measure", but that costs about 40 dollars in gaskets + god knows how much in tools. That  makes me start wondering if I should go ahead and put a piston in if I am going through that trouble. Round and round in circles I go wondering if my piston is going to shatter or if this is the normal sound.

I sort of miss the sleeved RD engines with their cheap + reusable head gaskets and cheap pistons

[tharden]

The kx500 cylinder if not modified can not be bored over as they are plated.  I have the same plans for my engine.  I do not have any noise and it is fairly powerful, but in about three months I am going to completly overhaul it.  I plan on doing the following.  New piston, shaved head, new main bearings and seals, v-force reeds and block, new clutch, and check crank clock.  The cost is not bad as my motor is stock and 8 years old.  It still produces 162psi compression, and I have not really ran it since fixing alot of neglected problems that it had.  My advice, if you are going to take the time to take the motor down do it right and the motor will do you right.

[Johnniespeed]

Guys
 It just isnt that big of a job to remove the piston and have a look. It takes more time to wash my truck than remove the piston from my KX500.
  If you have an oversize piston, that is  a major red flag and my concern is WHO replated the cylinder ?
 The steering head shake will be eliminated by a steering damper, I happen to use GPR but there are also Scotts and WER brand available.
 When I hear engine noises, that means my pipe mount is broken again. After a new mount my engine sounds great.
 Take a look at your piston and throw that dented pipe away. ( unless you have a friend who repairs pipes )
 Just my thoughts anyway.
 John

[oic0]

Guys
 It just isnt that big of a job to remove the piston and have a look. It takes more time to wash my truck than remove the piston from my KX500.
  If you have an oversize piston, that is  a major red flag and my concern is WHO replated the cylinder ?
 The steering head shake will be eliminated by a steering damper, I happen to use GPR but there are also Scotts and WER brand available.
 When I hear engine noises, that means my pipe mount is broken again. After a new mount my engine sounds great.
 Take a look at your piston and throw that dented pipe away. ( unless you have a friend who repairs pipes )
 Just my thoughts anyway.
 John

Its already got a new Pro Circuit on it. I also replaced all of the pipe mounts (though I did forget and leave the little copper ring out). I warmed it up yesterday and it didn't get any quieter.

It really isn't all that easy to just open it up and look inside though. Costs 30-40 bucks for a peek! Worse than a strip club. I do realize I am going to have to though. Both the back and front wheels also have 2 or 3 ruined spokes each and I think the front wheel may not be true. Mortgage, bills, and gas going up again. Going to be a while before I can get it all fixed up.