Kawasaki Ninja ZX Forum banner
1 - 16 of 16 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter · #1 ·
So, I picked up an 85 ZX900 in a trade and took it into a shop to have the carbs redone. The bike wasn't running when I got it but I knew the carbs needed to be redone so that's where I started.

Well, once the carbs were rebuilt, the mechanic called and said the bike wouldn't start and when he did a compression test all the cylinders tested "well below 100." He wouldn't be real specific about the exact numbers though until I pinned him down. Then all he would say is the were in the 60s and one might have been around 45.

A friend who is a mechanic in Colorado said that it would be really unusual for all four cylinders to be so low and instead usually two are low and the rest are high or one is low and the rest are good. But, to have all four so low is really rare.

First thing I'm going to do is take it to a different shop and get a second opinion. However, I'm still a little unsure about what I should and shouldn't believe.

The mechanic doesn't seem interested in doing anymore work on the bike and hasn't really given me a solid estimate for the rebuild work. He did say "around $1400" but that was it. When I pressed him he said that was a guess and he hadn't even checked parts yet. I felt like he really didn't want to do anymore work on the bike and simply wanted his money for what he had done and I could be on my way.

As I said earlier, I'm unsure if this guy simply wanted to get my bike out of his shop once he realized there was going to be a slight challenge in getting it fired up. My bike was the only true "sportbike" in the shop, the rest were 70s and 80s standards and cruisers.

I'm at a loss at this point about where to go other than the second opinion.

Anyone have thoughts on whether the compression would or should show low in all four cylinders or if that sounds "strange" as I was told by one guy.
 

·
Registered
Joined
·
494 Posts
You need to find out where it's leaking from first.

Get someone to do a leak down test on each cylinder... or you can go out and spend the $100 for the tester and do it yourself.

Basically you hold the crankshaft in place, set one of the pistons at TDC of compression stroke, and hook up the tester. It'll fire air into the cylinder and you listen at:
1) airbox - if you hear wind it's leaking past the intake valve
2) exhaust - leaking past exhaust valve
3) oil filler hole - leaking past the rings

Then you've got a vague idea of what needs to be replaced. Rings are cheaper then valves.
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #4 ·
I'm picking it up Saturday from the shop that has it which didn't do such a thorough job of chedking things out and bringing it somewhere else. When I explained to new shop what happened at the first they were skeptical about the methods the other shop used. Although they did readily admit the engine could be shot, they just didn't feel enough was done to confirm it.


The first shop didn't do a leak down test, didn't try anything to see if it effected the compression and just did a compression test and declared the bike's engine dead.

They also showed no interest in explaining to me what else could be tried to verify that the engine is dead and it might be. I just don't think they did a good enough job of confirming anything. He didn't even retry the compression test after getting such abnormal readings.
 

·
Registered
Joined
·
494 Posts
More then likely he didn't feel comfortable doing an engine rebuild. I don't blame him... there are a lot of things that can go wrong when you rebuild an engine. So many pieces with tolerances so tight you can't even begin to imagine. And if you fuck it up... then you're out several thousand dollars.

Though the shop should have been honest and just said, "it'll need work, we don't feel comfortable doing it."
 

·
Registered
Joined
·
683 Posts
Maybe it has a problem thats not such a big deal. I'd take the valve cover off and check the timing chain. maybe the chain got loose and the cam timing got out of whack. Maybe bad valves. Holes / notches burned in the valves or bent valves. If this were the case and the pistons didn't get too beat up, you could probably be rolling again with new valves, a valve job a new timing chain and some gaskets. Sounds like a lot of work and money, but its certainly less than a complete rebuild. Then again, if I were going that far I'd probably put a piston kit in it too. Just some ideas.
Tom
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #7 ·
Thanks for the ideas Tom. But, instead of working on it mysel I'm going to take it to another shop and here is the fun part. Both are saying they will verify the engine needs to be replaced or see if it is one of the issuses that Kawi T mentioned. From there, however, they take completely different pats. One says they will rebuild the engine if needed for $700 and that it will include "everything," valves, bearings, everything. The other said they don't recommend rebuilding these engines because of the age of the bike. That instead they also try to find a good used engine and go that route instead. The service manager said they do that because whenever they open one of the old engines, in particular these kawi zx900s, something will break and since parts aren't readily available it can cause a big problem.

The big question is - which one do I trust?
 

·
Registered
Joined
·
494 Posts
$700 to rebuild an engine...

That seems hella hella cheap. Especially considering the fact that the bike is 20+ years old. Chances are good he wouldn't be able to get all the parts. An engine rebuild (strip to the crank) is at least 14 hours worth of work. Before parts.

So he'd have to be charging $50 an hour and not charging for parts at all.
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #9 ·
That's the route I'm going. The guy offered to diagnose it for nothing and do the rebuild if needed. He's the only person in Columbus willing to do it. The way the rest of the shops feel, I will give up on the bike and leave it at the shop since they think the rebuild is worth more than the bike.

But, I like the bike and want to keep it on the road. I'm in it for so little that even another $1500 wouldn't put in in a bad place on it.

Motorcycle shops really put people with an older bike in a bad spot. They aren't willing to work on them so we have no choice but to dump them or do the work ourself. Then, if we're medically limited like I am it prices me out of the motorcycle market.

Yes, I understand they get stuck by motorcycle owners but then, they picked their line of work. OK, I'm done bitching.
 

·
Registered
Joined
·
228 Posts
It's a sad state of affairs when mechanics worry more about getting a quick job to earn their bonus than looking after a customer willing to pay to get a fairly difficult and/or time consuming job done. Feel free to moan on some more!

Hope you get some satisfaction with the chap you've left it with, you obviousely have bonded with this bike to go to this much effort and it would be great if you can get it going.
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #11 ·
At this point, I'm on my own since the mechanic who was going to do the rebuild never called me back.
 

·
Registered
Joined
·
138 Posts
I agree with Kawi_T, get yourself a compression tester and chec it yourself.Hell it will take me forever to type all the shit you can try yourself. If you want some more info on the bike,spend 5 bucks on long distance and call me,hell if you want call me collect I'd be glad to help. 1-403-704-0825.Crowd.
 

·
Registered
Joined
·
138 Posts
Hay Sev. Where at in Alberta?:headscratch
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #15 ·
I agree with Kawi_T, get yourself a compression tester and chec it yourself.Hell it will take me forever to type all the shit you can try yourself. If you want some more info on the bike,spend 5 bucks on long distance and call me,hell if you want call me collect I'd be glad to help. 1-403-704-0825.Crowd.

I appreciate the offer and will take you up on it. Thanks to everyone else as well.
 
1 - 16 of 16 Posts
Top