Valve adjustment for the GZ250
 

I've mentioned that I have a friend who used to be a motorcycle shop mechanic and has had several promotions since then so he is a national motorcycle maintenance expert. This guy is a real resource for motorcycle information and a lot of other things. And a good friend.
Today he came over to adjust my valves and I said in this forum that I would report back on what he said and did. He said that most people had no idea if their valves needed adjusting or not. If they are too tight that is bad and too loose is bad. If they get out of adjustment it could toast your engine and most people simply would never know it was coming.
So how do you know if they need adjusting? You never would. He said to make the first adjustment at about 5000 miles (mine has 5400 right now) and about 5000 miles after that. Best is to get it done about 5000 and then every 5000 miles. Sometimes you go in there and they don't need any adjustment, but then you are sure it is right.
He says this has a very small effect on performance and even on valve noise. Too quiet is bad as the valves are probably too tight (mine were).
I offered to ride the bike to his house, but he said that it takes the engine so long (2 hrs.) to really cool down that it was easier for him to just come to my house. I won't tell everything he did, but it started with taking the gas tank off. Then the chrome cover on the left side where the spark plug is. My spark plug was loose, but no damage had occured. My plug looked great. Then he tried to take off the small plate on the left side of the engine to be able to move the piston to TDC. But the plate would not budge so rather than bung up the plate we put the bike in 4th gear and by moving the bike that moved the piston (without the plug there was no compression so it was easy) back and forth until the piston was at TDC. It comes to TDC twice and you want it at TDC on the compression stoke. Hard to know when this is, but when the valves are loose that is it (valve caps are off. Labeled #1 and #2, put them back the same way).
Loosing the nuts and adjusting the "valve adjustment screws" and tighting the nuts was tough. There are two valves: exhaust in the front and intake in the rear. He adjusted both and put everything back together. I videoed all of this so I can do it the next time.
Honestly, this was pretty hard to do and I don't think the average rider should attempt it.
Probably $100 at a shop. With my video I think I will do it, but just starting from scratch I don't think anyone should try this. Unless you have done this on other engines.
So it went well and I owe him a big favor. Just thought you would want to know.

Chris, retired, Atlanta

Re: Valve adjustment for the GZ250
 

No pictures? Can you capture any stills from your video? Or post the video somewhere?

Re: Valve adjustment for the GZ250
 

Thanks for the post Chris. Your remarks at the end made me think a bit on some of the advice I have given on this forum. It is true that if someone has little or no experience at something it is much more difficult for them. I have 53 years of experience (since I was 5 or so) of wrenching on my own "bikes". I have totally rebuilt a number of vehicles, motorcycles and cars, including engine and transmission overhauls, as well as working as a professional mechanic for a good while. So while it is easy for me to say "just do it", I realize it is not that easy do do without the experience, tools and know how I may have accumulated over the years. To me doing a valve adjustment on the GZ is about as hard as putting a band aid on a cut would be for a surgeon. You don't want me doing surgery though, believe me! Even if I had a video! :lol:

Re: Valve adjustment for the GZ250
 

:plus1:

Great post. I agree with all of it. Important parts above. :tup:

Knowing that it is somewhat of a gamble, I still think that I will only check mine every 10K or so....but he (and the Zuki) manual are correct that they really SHOULD be done more often.

Re: Valve adjustment for the GZ250
 

Well said mr. softie.

My father was a mechanic all his life.
He kept a small school with about 8-10 buses running for 10 years.
In the 50's and 60's you did everything hand, and rebuilt all that you could.
Dad would buy cars and trucks that did not run, rebuild them,paint them, sell them.
I was the clean up boy on the engines, scrape off the old gaskets.

The real lesson we both got is when we began a trucking operation as owner operators.
I have fixed flats on everything from a bicycle to cars, trucks, tractors, and of course big trucks.

The only tire that I could not change by hand was a golf cart tire, too wide to get a grip on.

This is why I would rather do it myself. I care, but does the tech??

Re: Valve adjustment for the GZ250
 

And if it's not a matter of care, it may be one of ability/experience. I think Alan alluded to this kind of thing on another thread when he talked about how dealerships put inexperienced techs in place b/c of the high turnover rate. Unfortunately for folks like me, who did not grow up wrenching on bikes, cars or anything else, we're kind of at the mercy of the mechanics, dealers, etc. The best you can do is try to educate yourself at least somewhat (like with this forum), but if my mechanic says I need to do something, in the end, you have to take a leap of faith. That's why I try to form a relationship with a mechanic and then be loyal as hell and send him business. We all do this, really. You have a doctor or a dentist? Same thing. Pilot of an airplane? Same thing. Amazing how we put our lives in other people's hands all the time.

kk

Re: Valve adjustment for the GZ250
 

A good tech that you know and trust is a good thing. Get their knowledge.

Just going to a shop......is the tech having a bad day? bad week? bad life?

Yes, boards like this, is very valuable to everyone. Each person is not going to have the same problem, so we can all glean some information from each other.

Most machines are not that different.
Air, fuel, and combustion is all it takes.
Now the hard part is to get them to all work at the right time.

Jerry

Re: Valve adjustment for the GZ250
 

Probably! :lol:

Re: Valve adjustment for the GZ250
 

No still pictures. ANd I have no idea how to get my VHS tape online. I thought of taking still pictures, but thought the video would help me better in the future. I got the video with his audio comments, etc.

Ride safe, ride long.

Chris, Atlanta Just waiting on warm weather.

Re: Valve adjustment for the GZ250
 

Chris,

Is it a digital video camera? Or analog? What size tape? Or, what is the make and model of the camera you shot it with?

Video can usually be easily converted to a computer playable format, but, like mechanical stuff, you have to have the right tools. It's sometimes easier (but not cheaper) to take it to a video shop.