TOPIC:

How bad does this look? its a kz550 ltd -

Now this is bigger:
www.guavatone.com/free/KZ550pit.jpg
other side
Post edited by: guavatone, at: 2006/02/25 16:43

Post edited by: guavatone, at: 2006/02/25 16:46

that's better...

I'm with Jay, fix it. I've seen auto heads that looked better and still leaked.

-Duck

Post edited by: Duck, at: 2006/02/25 16:09

i dont know if this will be any help but i played with the pic some.

blown up this large that arnt as clear an im sure you all would like, if these replys are not useful i can remove them!

thats not good. you might be able to mill the head a little to clean up the gasket surface enough to seal. the combustion chaber is a little bit tougher those craters are going to create hot spots ,but if you grind on that combustion chamber too much your compression is going to disapear. i think i would try and find another head and use the best parts of the 2 it would probably be cheaper than fixing this head i think. goodluck,happy wrenching!

The dings in the head surface are right where the sealing ring on the head gasket goes. It will be a leaker. You need to surface that head when you rebuild it.

Jay

What difference would I see if I mill the surface? This is only a 550 - I've gotten advice from others saying, "just get it running". The thing is that this is a head from ebay $50. The old head had vavles cut and resurfaced. But the cam cap bolts kept stripping away the aluminum head whenever I tried to torque the caps down. Arg......

I do appreciat opinoins from every angle....... but what could happen with these "hot spots"?
Most folks I talk to seem to think "ahh its only a 550 " I guess they are saying that its not too much power to begin with so "why bother".


Can anyone predict the differences in a milled head vs. these pits?

I replaced the old pics with 928k. Thanks for blowing up the pics hard.

Post edited by: guavatone, at: 2006/02/25 16:41

now for the rest of story.have you tried heli coiling your other head?your head gasket will not seal right unless you can get the surface flat and straight but when you mill the head too much you change clearances on valves/pistons extra slack in cam chain also needs to be taken up by adjuster,cam sprockets might need to be slotted to adjust cam timing........,id try heli-coiling cam cap bolts in other head.

The problem with the other head is that I didn't know which threads to helicoil. I stripped one thread, took it to a machine shop, they put a steel inset thread in, I tried again and a completely different thread stripped. It just really pissed me off at that point since I had no way of knowing which threads were bad.

Now that was very far from "The Zen of Motorcycle Maintenance"

Anyway, You think its safe to helicoil for cam caps? Sould I just go back and helicoil each one?

Seems to me like installing inserts in all the cam cap bolt holes might be the way to go.

Anyone that says "it's only a 550" is generally not worth listening to

I think that is right in line with "The Zen Of Motorcycle Maintenance", I had to read that book twice before I understood it

And lets not even get started on the definition of "Quality", that almost drove me insane.

Post edited by: steell, at: 2006/02/25 16:48

like steel said do them all,installing heli -coils isnt that complicated just take your time and follow the instructions no need to pay machine shop to do it.id recomend removing valves before hand to make it easier to clean shavings out .mark your valves so they go back in same place!goodluck,happy wrenching!

Shavings from what? Have you helicoiled in these places? seems like alot of preasure. Sorry if I seem cynical but as you can see it seems I have been getting poor advice.

Oh, the logic of the advise for a new/used head was that "if the aluminum head is not keeping threads, then maybe the aluminum is too old and corroding to be of use" - any ideas on that one?

Thanks so much for you time.

Post edited by: guavatone, at: 2006/02/25 16:54