First Top End rebuild - Need advice - Pics included

[stewart]

i would not hone it with anything but the brush set up  that wiesco  sells for  plated cylinders

[Jeeks]

I liberally spray WD-40 in the cylinder then use a Snap-On ball hone in a cordless drill on high speed.  Move the drill up and down pretty fast to create about a 30-35 degree cross hatch.  Only hone for 10-15 seconds to remove any glazing, scoring or metal transfer.  Been doing it for years, never a problem.

BTW -  that was a basket case engine I rebuilt. Here's the details.  http://www.thumpertalk.com/forum/showthread.php?t=594486

[BDI]

What's your piston to cylinder clearance? looking at the third picture It looks excessive. Are you sure the plating is not worn threw that aluminum colored spot shows up in all your pictures

[Jeeks]

What's your piston to cylinder clearance? looking at the third picture It looks excessive. Are you sure the plating is not worn threw that aluminum colored spot shows up in all your pistures

lol - no dude.  This wasn't my first engine rebuild.  lol

[BDI]

LOL-Ok it just looks funny in the picture I guess. I have rebuilt one or two motors myself. LOL

[joker_fly]

Im doing a topend rebuild also, but o cant figure out if i got an twisted actuator out off the kips assembly like the one in the pic. Does any one have a pic on where it belongs ?

[Jeeks]

That pic was only to show how good the gasket remover works on decarbonizing.  That's a 250 KIPS.

[BDI]

i would not hone it with anything but the brush set up  that wiesco  sells for  plated cylinders

               Hey Stewart why wouldn't you use a ball hone?

[stewart]

its been my opion that the size or diameter of the bore and proper piston clearance is not achived by using a ball hone  and if those sizes are right bore dia . striaght ness .etc..... the cylinder that his been plated makes better power the more its been run and  and deglassing it did not improve the power on a plated cylinder

[Kawasakinut]

Im doing a topend rebuild also, but o cant figure out if i got an twisted actuator out off the kips assembly like the one in the pic. Does any one have a pic on where it belongs ?

i've got the same question about the twisted piece? w.t.h.d.t.c.f "where the heck did that come from"? i could of sworn i followed my service manual instructions.

[Kawasakinut]

its been my opion that the size or diameter of the bore and proper piston clearance is not achived by using a ball hone  and if those sizes are right bore dia . striaght ness .etc..... the cylinder that his been plated makes better power the more its been run and  and deglassing it did not improve the power on a plated cylinder

stewart i thought the ball hone was used to make the cross hack in the cylinder which makes for even oil flow throughout the cylinder. i'm not sure about the performance aspect. the ball hone takes nothing away from the cylinder just creates peaks and valleys. ok takes a little (mi-nute amount).   

[Jeeks]

BTW: This only pertains to the KX250 NOT 500!  Didn't intend to hi-jack the thread.

The piece that looks like a twisted gear is the Main Valve Rod.  Look on the front of your cylinder for a little cap that looks like a number '8', it has a phillips screw holding it in.  The end of the rod has a notch cut in it, that notch will be toward the front of the engine when installed.

[Jeeks]

its been my opion that the size or diameter of the bore and proper piston clearance is not achived by using a ball hone  and if those sizes are right bore dia . striaght ness .etc..... the cylinder that his been plated makes better power the more its been run and  and deglassing it did not improve the power on a plated cylinder

I don't use the hone to adjust the cylinder size in any way.  I like to have a clean surface for the new rings to seat to without any wear from the previous piston.  Just like sanding down a shaft when you install a new seal.

[stewart]

i think honeing to a size for proper clearnce and cross hatch is essentiol  for 2 or four stroke...i think deglazing the bore on a nonplated  cylinder is fine 2 or 4 stroke  they look nice ...  but on a plated 2 stroke bore i  found more power in the cylinder the longer i ran it with just changing pistons and rings  no deglazing the where the  bore size was right on size ....wiesco siad they sold a  diamond whip type brush for 2 stroke deglaze .. but were not to big on ballbrushing  ..i belive the plating laps to  a better seal after more run time ...ps i used to work directly with sunnen  hone  company on new  engine  cylinder manufacture  for cessnea aircraft  and was a counsltant for some major rebuilders on honing

[Kawasakinut]

stewart now i don't know what i want to do on my cylinder! yicks i'ma cornfused .