PIT STOP PERFORMANCE: Valve Job for $148????

To do a valve job, you grind. The amount of grinding on a valve seat for a Kawasaki is not near as much as on a car. I am not suggesting you use Larry (although he would be a good choice)... I am saying that it is a real poor idea to get valve seats recut by a person that does mostly automobile work. Larry's work seems to be high end performance stuff but I bet he would do a routine old valve job a whole lot better than Bubba down at the NAPA. In fact, MOST big cities have only one or two bike-oriented machine shops and many only work on bike stuff. Cheap and reasonable? If the guy cuts your seats down 1/4" and you can't shim the valves, it won't seem so cheap and reasonable. The reason I bring this up is that I have personal experience with it and have seen it happen a number of times. If the person who is doing the work has a solid reputation in the bike business, then go for it.

As far as grinding Kawasaki valves, you grind the stems so that the length can be adjusted... they come new longish. When you recut the seats, they often need to be reground a tad so you can use shims in the middle of the range... 250-260, etc. You put the valve into a gizmo that spins the end against a cutting wheel type thing. I guess you could do it youself but not sure how you could get the valve stem ends flat using hand tools.

You would be amazed at how much seat material there is in a KZ head to work with guys....

What I've seen come from many automotive shops are generic valve jobs. They get in there, wack in a big fat 45* cut, grind the valve faces, tip the valves and send it out the door. NOT ALL DO THAT.

Will it work. Yep.

Is it the best thing for performance . Nope.

As long as the OEM valves are straight and there's enough margin left to them, they can generally be reused. They have no specail coating.

If it's never been touched before, the Exhaust valves on a KZ head need to be sunk quite a bit. The seats are way up close the the port side of the seat and too small to be fully effective. A car guy might not care.

The guy on that discount site OMR pointed everyone to, claims to have 30 years experience. If that's the case, dont let something like the valve jobs being done with grinding stones bother you. They work and work dam good.

I go by stem height when I setup a valve job. It's nice the guy offers to include bench shimming the valves. Just don't count on that clearance being exactly the same after you torque the head on the motor and the cams in the head. Always double check things like that. It's common sense.

I've had heads come to me fresh from a machine shop where everything was cut with machines. Every valve in every port was leaking light by the seat and the valve. The guys found me and said "please fix this"

I've seen that on motorcycle and car heads and fixed both.

It's not the machines used. It's the skills of the people using the machines.

A high dollar tool in the hands of a fool can do more damage than a took kit wrench in the hands of a professional...

Are ya catching my drift on this stuff yet?

The only thing I'm trying to sell you here is good advice from someone who's been around the block a few times. I'm 52 and have been doing this since my 20's.

If you don't know what you're looking at to start with, How can you tell if you have something good in your hands when you get it back?

Would you know a diamond if you held it in your hand? Hell no, I wouldn't....but I'd dam sure pick out a bad valve job in short order....

Have fun & put away the Walmart Shopper mind set when you buld motorcycle engines....

Larry C

I worked in a automotive machine shop for quite a few years, and there was a hell of a difference between bikes and cars,,

As stated go with someone who has the knowledge to work on a motorcycle head, they will know all the little ins and outs in makeing a head right.

One thing I noticed in his ad, this is a very basic valve job. he didnt mention checking the surface to make sure its flat, nor did he say anything about checking/shimming the springs.
I am sure he can do it but the cost will go up, just how much?

Do they make block plates for honing KZ900/1000 motors? Years back I use to race FE Fords {428 Cobrajets} and we discovered that by doing the valve jobs with the block plate bolted on the head we could keep the 2 end exhaust valves from leaking as they do with an ordinary valve job. Has anyone tried doing a Kaw head this way ?

How would head bolt torque affect the valve clearnces?your not putting any additional down pressure on the cams or the caps.

So... I am pretty inexperienced when it comes to valves and the such...
First... when should a valve job be done? When starting to lose compression?
Second.. do you want to go ahead and get your cylinders bored and all while your doing a valve job?

Also... I didnt realize it was so cheap, with respect to what has been said, but everyone in my town has told me hell no there not touching an old bike or... 1100 dollars and about 2 weeks.... I supply the parts.

Basically I am poor... and where would a good place to send it off be.. and get some peace of mind that I am not getting hosed.

All,

Kind of surprised how this post (& the Hydrulic posting for that matter)turned out for no way did I want a flame war or hurt feelings to come out of it.

While waiting for my parts I came across what seemed a decent deal and was just wondering if anyone has heard of them or has used them in the past.

May work for others looking for a basic valve job, for what I'm doing on my bike, well I need a little more than just the basic, Cavanaugh Racing Heads...

Sorry to stir up the pot for no better choice of words...

OMR

This ain't a flame war, we've had a few of those and this one isn't one of them :laugh:


Seems like a pretty civil discussion to me, lot's of different opinions, along with lot's of good info.

And the same applies to the hydraulic clutch thread (where I'm headed next to see if there's anyone I can argue with)

Getting mixed signals. Quick recap.....

-$148 for a valve job is a great deal assuming the shop is competent.

-Auto machine shops should be avoided.

-No one has any direct experience with this particular shop, either good or bad (or did I miss it).

-Paying less than $XXX for a valve job means your a cheap sucker (where XXX equals what me and/or my buddies paid/charge for same).

-Georgia Bulldogs will win the National Championship after defeating USC by three touchdowns. (Oops, wrong forum!) :silly:

One thing about these KZ heads is most need guides too. You can't just do a valve job with worn guides.

Jay

76 LTD wrote:

How would head bolt torque affect the valve clearnces?your not putting any additional down pressure on the cams or the caps.

The head was previously unloaded [so to speak], now you torque it to the engine and the head has stress points with load on them. Metal can and often will distort to some extent.

It take's only a few minutes to give the valve clearances a final check afer the head is torqued to the motor and the cams torqued in the head. There is no good reason to not perform that step.

A bench shim job is a helpful thing to provide someone. I'm not kicking that concept at all. Just go the rest of the way and do the final inspection. Correct what's needed / if needed and you're further up the road to firing up your motor without problems.

Bench shimming is really to find out if you have some that are too tight, before you install the head and have to remove it again and buy another gasket.

Yes they should be checked again after installation.

Jay