Richo507's ZL900

[richo507]

Hey, I joined back at the end of May, but haven't taken the time to post about my bike.

Basically, I've figured out that I got really lucky on the other used bikes I've bought. I missed all kinds of sh!t on this one.

When I got it home, I noticed some minor things wrong, like the boot from the trans to the driveshaft tube wasn't quite on right.

After riding it for a couple of days, the oil started leaking. Just a steady drip onto the exhaust from between the oil pan and the rest of the case. I noticed some other things, and decided to start tearing into it. I've pretty much figured out that it musta been in pieces at one point. Everything under the top frame tube was all tangled up and/or wrong. A bunch of the gaskets have obviously been redone with goop, and the worst of it is that I've found 5 bolts that are 1/4-20 instead of M6, and pretty much stripped out (water pump, clutch housing, bevel gear case).

The good part is that it runs like a top (or at least did until I took it all apart), and now I probably know my way around my bike better than my wife (just kiddin', wifey!).

This weekend, I'm going to try to use those HeliCoil thread inserts to fix the water pump and clutch threads (and maybe the bevel gear case too), and redo the oil pan gasket (can I use liquid, or should I get the real thing?).

I found the service maunals and the owners manual online (thanks ZL-OA for the GPZ900R manual!), and I've been pretty successful in getting it back together, but I've got some questions:



Oddball hoses to the carbs:

Fuel line from the tank:


I know this goes to the tee between carbs 2 & 3

Other Lines:


In the manual, it shows a hose going to the #2 carb vacuum nipple, and two hoses going to the tees between carbs 1 & 2 and 3 & 4. I think the two hoses to the tees go to the air swich valve. Where's the other one supposed to go? I read about people dead-ending the vacuum, but it's gotta be there for a reason, right? I just noticed that the GPZ900R manual gives some insight about running vs. engine braking.


Fuel Tap:

The breather line is supposed to go to the smaller outlet, right? (It was connected to a vacuum line before)


Clutch line routing:

I know it basically follows the LH frame tube, starting on the outboard side, going under a retaining clamp attached to the upper radiator mount, then sneaking around to the inboard side. Is there supposed to be something holding it in place near the bottom of the frame tube? It seems too loose. I'll probably just zip-tie it or something, but it'd be nice to know how it's "supposed" to go.


Fuel tank cap:

Can someone post a picture of the bottom of theirs? When I got it, it rattled like a mofo. At my first fillup it was leakin. I took it apart, and put the rubber part on the outside, and that seemed to get rid of most of the problem, but something still don't seem right.




Anyway thanks for the great site, and hope I can return some favors sometime...

Rich

[richo507]

First of all, I wanted to give a big thanks to zlMark for a lengthy phone conversation on Saturday. Thanks for answering my questions, and for the tips re the tank and the fuel valve. Hope your boy's better.

HeliCoiling the water pump bosses went really well. Based on:
1 How well it went on the water pump
2 zlMark's advice to check the wheel bearings
3 Not trusting the liquid gasket
4 Finding a bevel gear case gasket cheap on ebay
5 What's the worst thing that can happen?
I decided to take the plunge and HeliCoil the stripped bevel gear case bosses.

As a good number of you know, this required the removal of the rear tire, and the swing arm. A big job, but what's the worst thing that can happen?

(As you're reading this, right now would be a time to take a moment and give thanks that you're not me)

So I get to work. First thing I find out is that the RH rear wheel bearing dust cover's mauled and that bearing's on it's way out.

When I pulled the final drive off, the driveshaft spring was kind of torqued up. More on that later...

After pulling the shocks off (one attachment point missing its washer), it's time to get the swing arm pins out. I remove the RH cap, and retainer, and find 4 holes, 3 with broken-off taps in 'em, and the other stripped out. Since taps are hardened, and hardened=brittle, I used an expendable screwdriver to chip away at one of them until I could tease the last of it out. The threads left behind were good enough for me to use to pull it. The other side has an extra hole with good threads. It comes out OK.

On the swing arm, both dust caps are pretty beat up, and I can't turn the LH bearing. The driveshaft comes out no problem seeeing as how the pin and spring are long gone. Guess that's how the spring at the other end got torqued up.

I get the gear case cover off, and spend a couple of minutes basking in my glory of my triumph before discovering how fu**ed I am. When the @$%!#$ MOFO PO used his 1/4-20 on the rear bolt hole, he completely broke the boss off the case. Apparently, deciding that would be a bad thing to repeat, he bored out the hole for the top bolt, but drilled it at such a stupid angle, he started coming out the side of the boss.

Pictures are attached. God, I really don't want to pull the engine, strip the case, and get new bosses welded on. Don't even know how good that'll be in terms of warpage and overall strength. I know cast iron gets brittle when you try to weld it, not sure about Al. We have an aluminum mig setup at work. I might try and throw the whole thing into my pickup bed & bring it in and try welding it as-is.

Anyone got the benefit of experience on this?

[Hoss]

Wholy shamoley! Talk about dirty little secrets... That sucks! Good luck fixing it, and make sure to keep us updated on what you decide.

I'm sure that the best and correct way to do it would be to pull the engine and separate the cases and get them proffesionally tig'd into place.

Kinda hard to tell from the pics, and I've never had mine apart back there, but there might be enough room to get a cutoff tool in there and cut the old bosses out and you could use your alum mig welder to weld a couple square blocks of alum in there, then drill/tap new holes, and grind flush with the case...

sounds like a pain in the A$$ either way!

Good luck.

[gosupes]

Pictures are attached. God, I really don't want to pull the engine, strip the case, and get new bosses welded on. Don't even know how good that'll be in terms of warpage and overall strength. I know cast iron gets brittle when you try to weld it, not sure about Al. We have an aluminum mig setup at work. I might try and throw the whole thing into my pickup bed & bring it in and try welding it as-is.

Anyone got the benefit of experience on this?
Aluminum welds are fine to machine or drill. What you might find is that the case is made from cast aluminum with nice machined surfaces. Some grades used in casting are less than desireable for welding. Impurities can make laying a bead a PITA. Steel and other alloys are more tolerant of impurities. Aluminum is not. I say give it a try, got nothing to lose. Sorry to hear about the run of bad luck.

[golddrakul]

May want to keep an eye on eBay, case halves show up occasionally. There is a link from the home page.

[richo507]

Heh... One's on the top half, the other's on the bottom.

Talked to a guy at the local welding supply.

He has Al flux in a bottle and Al TIG rod I can try to braze with.

He said I'd be fighting the oil that probably impregnated the cast material, and that the alloy would be hard to match (probably Al-Mg).

He said the pro way it's done is you take the whole thing apart, steam clean the case to get rid of the oil, pre-heat it to 300-400F, clamp it down to a table to eliminate warp, then TIG it with rod that approximates the base alloy.

He said MIG would be pretty unlikely to work due to higher heat, and an extreme unlikelihood of matching the alloy.

I'm gonna try brazing this weekend.

Tell ya how it goes.

[zlMark]

Rich, sorry to hear all the troubles. The boy is still sick, they finally figured out tuesday it's a bacterial infection. Today is his first day of very slight improvement. It has been very stressful to have to wait and see which direction he is headed.

Have you thought about that alumalloy crap?