On the 700, the allowed max bore diameter is 82.09 mm, or not more than 0.05 mm difference between the front and rear jugs.

Also check the ring thickness and replace them if out of service limit.

If you go over-bore when rebuilding, rejetting the carbs might be necessary. In my experience with the KFX700, twin exhaust setup alone really improves the top end power.

 

Well I got started. The jugs and pistion look almost new. Im starting to wonder if I should have tore into it so soon. The jugs have no scaring they have very very light scratchs. You can see them but its almost like looking at hon markings. What is the stock bore on this bike? My mic has a reading of 81.75 on the jugs and the pistion is 81.something cant rember now.

 

The KFX700 has a decompression system on the cam. 40 to 60 is normal for them.

Now that you have it down, hone it, rering it, regasket it and go have fun. As far as the noise, could be tons of things.

 

okay guys this thread is getting pretty long and Im very sorry for that but we have more work to do.

When I took the top end off I noticed that the ''F"" mark onthe the front cylinder was faceing the intake side and The ''F'' mark on the rear cylinder was faceing the exhaust side. I THINK THERE IS SOMETHING UP WITH THAT. Some one has been in this engine before because the bolts that bolt the jug to the block have been changed, they are not stock bolts. The ''F'' 's should face what way when installing the pistion?

 

I don't know and my manual is in my shop adn I'm a little busy or I would look it up for you.

You might go to someplace like this and download a manual.

Free service manuals: Kawasaki KFX 700 V-Force service manual

I got one on line for free and had a friend print it out. Or you can burn it to a CD or DVD.

 

Yes, someone was jacking with the engine before you.


All Kawi quads are that way.

Now you shouldn't feel too bad about tearing into the engine so soon.

Get a factory service manual and do the job right.

 

Okay I got my book and just to make sure of placement of pistion, The F on both pistions should face the exhaust side of the jug or head if you will on both cylinders correct? I understand the ring placement on the pistion just not the [F] placement. Im some what of a retard I guess.

I took my jugs to my bore guy and he told me we should go one size bore over stock. What is stock bore and what size pistion should I order. I want to set this atv up to go fast but I want to ride the trails to.
Money is always a issue but this is what I want to do, I want to kill yamaha 450's.

I want to order the pistion kit to night so anyhelp would be great.

 

I took one of my rods off with out splitting the case. The bearings dont look as bad has the ones you showed me but I only took the one rod off. I can take the bearing out from the other rode that is still installed on the crank by sliding the rod over and the bearing comes out. Should the bearing be able to come out like that? There is up and down play in the rod, Should it have that kind of play.

 

if you get the rod by the end an pullit to you then push it away an you feel slack in the rod ,it needs to be looked at ,an as far as that goes anytime i do a top end on an older machine i do the bottom also as a fresh top end will put more stress on the rod bearings an ending up with the bottom going out, that could cause a lot of expensive damage, i have seen this sereral times on machines that they want to go to h/c pistons an cams for the power.

 

No!
Think about it. Up & down play means it's worn out and everytime the rod goes up & down, the crank journal is getting hammered by the rod! You've got to replace what's worn out and start fresh.