84 GPZ550 revival

[KittenMeat]

Went to rent a house in upstate NY and got myself a GPZ550 that has been stripped down, plastics removed. That was sitting in the garage when we rented the place. The owner gave me the title, a few bucks later I've got an essentially free bike.

Good news: New battery, the starter fires up, but no gas in the tank I guess so no turn over.

Bad News: I think whatever was left in the tank was probably water and varnish by now. I need to clean the carbs for sure. TK26 carbs on this model year.

What do I need to know about this model? It's the first of the "unitrack" with a single rear shock. It was riding fine earlier, but apparently needed a new clutch or clutch springs (slipping clutch?) which he gave me along with a carb cleaning kit and a bunch of brand new parts and fluids sitting around.

I want a little lightweight vintage ripper to take to watkins glen (right down the highway from me) for some track days (Or NYST track days) and weekend rides/cruises.

me before the owner of the house was like "you want it? pay me whenever I guess. I can't bring it with me"

anyone on here have one? I'm moving in a week across the country. Parts probably easier to find on the salt free coast here...

 

[Kawikiwi]

Subscribing and awaiting sweet, sweet updates

 

[Maddevill]

For sure the carbs need going through. along with the tank and petcock if there's any rust in there. Get the thing started to see how it sounds. If it's knocking like hell, give up and trash it. If it sounds good bleed the brakes and do the clutch job. Lube all the controls, get some new tires check the chain and go for a shakedown ride. Those things started the midweight sport bike wars and are a hoot to ride.

 

[Tally Whacker]

I have a soft spot for the GPZ 550, since I raced on one of those a hundred years ago.

Don't expect it to be light, though. They weighed more than most liter bikes do these days.

 

[GPzPop]

yay GPz's (see my user name!)
Please, Please, Please inspect the rear swingarm, and the components attaching the rear shock to it.

a known weak point on the earliest mono-shock versions, like 1983, idk about 1984,

the triangular metal plates the bottom of the shock attaches to, connect to the steel swing arm with woefully under engineered sheetmetal tabs, which can shear

if it has an aluminum swing arm, it may be OK

 

[KittenMeat]

yay GPz's (see my user name!)
Please, Please, Please inspect the rear swingarm, and the components attaching the rear shock to it.

a known weak point on the earliest mono-shock versions, like 1983, idk about 1984,

the triangular metal plates the bottom of the shock attaches to, connect to the steel swing arm with woefully under engineered sheetmetal tabs, which can shear

if it has an aluminum swing arm, it may be OK

is it possible to reinforce these with some steel or CNC alloy bits welded on? A buddy did something similar to reinforce his xr650r frame basically just adding braces.
I should have access to a welder there fairly soon. I'm going to do a series of videos going through learning it.

I've never cleaned carbs on my own before on a motorcycle, but I remember messing with them on cars as a kid. I've watched a few how to videos. The more I read about this bike the more I like it.

To me, the bike feels pretty light, but I was just riding a huge ADV bike for the last year, so it feels tiny.

I'll be there next friday reuinted with the bike again. Thank you for the tip!

 

[GPzPop]

is it possible to reinforce these with some steel or CNC alloy bits welded on? A buddy did something similar to reinforce his xr650r frame basically just adding braces.
I should have access to a welder there fairly soon. I'm going to do a series of videos going through learning it.

I've never cleaned carbs on my own before on a motorcycle, but I remember messing with them on cars as a kid. I've watched a few how to videos. The more I read about this bike the more I like it.

To me, the bike feels pretty light, but I was just riding a huge ADV bike for the last year, so it feels tiny.

I'll be there next friday reuinted with the bike again. Thank you for the tip!

yes, I learned to weld, so that I could fix mine, a short length of angle iron reinforces the tabs pretty well

also, barfer "Corey" used to race one of his in AFM super dinosaur classes, he is a great fountain of knowledge.

 

[KittenMeat]

I did some work on the GPZ. I made a stupid video because a couple friends and my parents enjoy it (I used to work on mechanical things in the garage as a kid/teen and my family would make tea and come watch as their weird child took the car apart again through the night)

[youtube]EXTxP_wlyBU[/youtube]

Summary: The bike runs. it runs really well. I should say it *RAN* really well until the rusty sludge in the tank clogged the fuel filter.

Right now:
replacing rubber fuel lines with clear silicone ones and adding clamps both to the vacuum line to petcock and fuel lines.

***Can I replace the rubber hose that goes to the carb with clear silicone tubing or is there too much heat and it will melt? I'd rather not go up in flames.

currently I'm using a vinegar bath inside the tank for a week to loosen the rust that may be in there. I already rinsed it out and drained most of the sludge but there's still a bit of rust in there.

***Is there something better I should be using? or is this fine?

It's mostly superficial at this point. the inside of the tank looks surprisingly good when I peer in there with a penlight



***I'm going to coat the tank next with RED-KOTE because it seems to have good reviews across the web for sealing the inside of a gas tank to rust and corrosion (especially with crappy ethanol gas. Thanks politicians.)

 

[Tim-That CX Guy]

If you use Red Kote, you will spend the rest of the bikes life chasing a carburetor demon.

I have personally had Red Kote fail three times, including a failure from a professional radiator company.
It dissolves in ethanol fuel, and leaves behind a residue that crystallized when it dries.

POR 15 or buy a new tank.

 

[Bikerx260]

That's not an 84, the 84-85 GPz 550's had an LCD fuel gauge on the tank and curved front edge of the tank. 81-83 had square edge tank like yours. Also the fuel cap is different from the different years. Engine wise, they are identical. The forks had shrader valves on the top of the fork but you shouldn't use them because the fork seals blow out easily with any air pressure added.

Pictured is the '85.

 

[KittenMeat]

you're right! It's an 83. I was surprised when I finally dug the old KY title out to try and get it titled in NY.

@tim-that cx guy : I canceled my order of red kote *just* in time
Ordered the POR 15 and will be doing that.

The paint stripper just got here today, gonna take the paint off and then sand down the rusty spot on the outside. It's currently POURING rain and it almost carried our trash can out to sea. The East coast weather is BIBLICAL compared to CA.

I can't wait to get this thing roaring again soon. I'll need to do something about the chopped rear frame. Gonna have to add a battery tray and frame hoop/slugs to tie it together.


Suspension Q's: what rear shock will fit on here? The stock one is well "weathered" although the pivots look good?

Also, what can be done about the front? I have some springs for it, but if it has a tendency to blow seals I know I could put some CBR forks or something like that on it...

 

[Slow Goat]

Sweet Barn Bike, Mr. Kitty.

It'll take some searching to find, but if you can pick up one of the cafe fairings they came with, you'll be stylin'.
BTW: Weren't all the GPZs of that era red in color?

Should be fun to watch this come along!

 

[Lex Talionis]

Congratulations on your very good luck! This has the potential to be an excellent urban scoot.

Do you know how long the motor sat w/o being run?

Did you just, simply, start it up w/o oiling the cylinders and valve train?

Lex

 

[KittenMeat]

Congratulations on your very good luck! This has the potential to be an excellent urban scoot.

Do you know how long the motor sat w/o being run?

Did you just, simply, start it up w/o oiling the cylinders and valve train?

Lex

apparently about 6 months. It had been taken apart and put back together.
right now I'm pulling the paint off the tank to fix some rust...
I've found a whole lot of bondo on one side of the tank. It was a good bondo job, but likely fixing more rust. The area behind the emblems is leaking the vinegar I had in there once I started scraping off the paint and rust in that area, so that needs to be addressed.

I'm thinking of ditching this tank entirely if it's more messed up than this, and finding another less borked up tank.

 

[two wheel tramp]

Off topic, best of luck, congratulations on finishing school Dr. Meow and please come back to the best coast.

 

[Kawikiwi]

Off topic, best of luck, congratulations on finishing school Dr. Meow and please come back to the best coast.

This ^ miss you already man. Hoping you're gifted with sunny skies once this thing is revived!

 

[Sharky]

apparently about 6 months. It had been taken apart and put back together.
right now I'm pulling the paint off the tank to fix some rust...
I've found a whole lot of bondo on one side of the tank. It was a good bondo job, but likely fixing more rust. The area behind the emblems is leaking the vinegar I had in there once I started scraping off the paint and rust in that area, so that needs to be addressed.

I'm thinking of ditching this tank entirely if it's more messed up than this, and finding another less borked up tank.

If the tank is already leaking from rust, I'd just scrounge up a replacement. There's enough gpz's out there so it shouldn't be hard to find a replacement.

 

[KittenMeat]

Tank progress:
When I got it: the paint job was good, but there was 33 years of paintwork underneath it.

Tried CitriStrip. It's nontoxic! You can use it indoors! It worked okay. But not really, and it was just as messy as the other stuff.
(Finally I stopped mucking around: Aircraft stripper. Dissapointed it didn't come with actual strippers.)

WOW that stuff works. Got some on my arm. OUCH. IT BURNS LIKE FIRE.

tank now: with really old bondo work. They didn't sand down all the paint, so its just kind blobbed over. Theres a couple dents they fixed. The main issue is here:

you can see that little area where the emblems usually bolt on? Well sadly there is a hole in the roof of the garage right over where it was parked. Water just sat in there and got spot rust right in that little annoying crevace.

I have no idea what to do, really. I sanded off all the surface rust, but there is some DEEP in there, and it's like cancer if you leave any left, it will just spread.

My thoughts:

A. Get the dremel/angle grinder out. cut the emblem area out completely, reweld another piece of metal on over it, or solder/weld a bead and fill the hole. I could also try brass and a brazing torch. That worked on my bicycle when I got a dent from getting too rad on it.

B: try dipping the whole damn tank in evaporust or Metal Rescue and get both the internal surface rust in the tank, and also the outside rust on the tank. Then solder the pinholes left, and coat the whole damn thing with POR15 like the previous user suggested.


Will coat with POR15 regardless, but I don't want to do this again, and I don't like doing things half assed. I prefer whole assing one thing at a time.


other stuff/life:
Rochester has been awesome. It's been hot here, but not humid and I realize it's been about the same in the bay. Hopefully work will bring me back out west for a fellowship. I plan to work with kids with autism and learning disabilities once I'm all done with everything. Right now I get to do a bit of everything and collect a REAL(TM) paycheck (and resident pay is REALLY good here in ROC. Not so much in CA. My buddies get paid 2/3 what I do and the cost of living is like 4x higher. If I end up working for the military/VA, all my debt goes poof!) Feels weird to be putting on the long white coat. Feels like I'm on the staff at hogwarts or something.

I'm riding around on a honda Ruckus right now. This thing is HILARIOUS. I'll get some videos. I'm a tiny dude so it can hit like 45mph with me on it!

 

[KittenMeat]

new tank, y'allz.

just finished POR15 on it today, gonna let it dry out a few days. had to do a tiny bit of modification to the frame/ignition brackets but it fits great!

just unplugged the wiring harness. Have an M Unit v2 from motogadget coming in to run all the electricals. had some issues with the old wiring grounding and shorting out, so just going to build a new harness for it.

can I get this thing running before september's DGR Rochester?!?

I still need to either buy a mig welder and do the rear hoop, or find someone local that can do it. I still need the Mig to make the brackets and stuff though.

 

[GPzPop]

Looking Good!