GT550 Cafe project

[imquattro]

After cleaning up the upper & lower portions of the case, it's getting close to re-assembly.
All the mating surfaces were lapped smooth to remove any imperfections from the glass bead blast cabinet.

The crank was soaked in mineral spirits for a couple hours, washed down with Gum Cutter 2+2, rinsed with brake clean, blown dry with air, then all the bearings & seals were lubed generously with new Valvoline 2 cycle motor oil. The seals fit nicely.


I have the upper case "mocked up."




After disassembling the check valves for cleaning and reassembling them I polished them. I did eventually used a glove due to the heat that soaks into them during the polishing process.


Installed:

[tz375]

Looks nice and clean. Did you clean out all the threads after bead blast? Those pesky beads get into everything. It's also a good idea to lightly countersink every tapped hole to remove the crowning that occurs when a bolt/screw is tightened.

When you are 110% ready to close the cases, wipe the mating faces clean with a clean rag and acetone and then apply a thin smear of 3 Bond to one surface and press the cases together by hand, and then insert the bolts.

Do the SRIS valves work and did the screens survive? I find that 2 out of three are non functional on average and teh screens are shot which is an issue as they are no longer available.

[imquattro]

The SRIS valves were non-functional when I got it apart. 2 were stuck closed, one was stuck open.
I diassembled them, cleaned them, made the springs uniform in length & shape (some were compressed) and reassembled. The work great now, you can suck only one way through now.
The screens were shot/holed/one missing when I opened it up. I've seen a few on fleabay but decided to forego them (they were an astronomical $ figure for 3 due to being made of 100% unobtainium).

The case: The fastener holes were cleared of blast, the mating surfaces of the cases were lapped smooth, & then the fastener holes were rinsed out w/ brake clean as was the case joining surfaces.
After the gear, clutch, starter gear, and crank were installed, I spread a thin uniform see-through layer of Permatex Aviation Form-a-gasket
on the sealing surfaces.
Threaded the rods through the front of the case, tapped the case together with my hand, and using the tightening sequence & torque specs, installed the fasteners.
Looks nice, I'll post pics later.

[imquattro]

I'll post pics later.

Later:

[TLRam1]

That is looking Nice!

[imquattro]

Well, some bad news, a slight work around, and settling for what it is....

The left bank was the crustiest of three, I suspect an oiling issue. It's bearings on the crank were the noisiest of the bunch too.
All bearings of that type exhibit some noise when spun dry and clean, but these were louder and I suspect had some, though none was visable (albeit there's not much you can see, but with a flashlight & magnifying glass, nothing was seen on the races or bearings.).
Since I'm not in a position to send the crank out to get rebuilt, let alone replace NLA bearings, I cleaned them up the best I could and pre-lubed them w/ 2 cycle oil. They're quite quiet with oil on them.
The wrist pin (gudgeon pin) and bearing showed wear too:

The one on the left is from the '74 and the right's from the '72. I'm using the '74 engine, so I used the nice 72's pin and bearing. I inspected the inside of the upper rod, and saw slight signs of wear, but it was minimal, and I'm not dealing with it (aka, crank disassembly blah blah blah. I suppose it could be honed out and an oversized bearing could be sourced and installed but....)

The pistons were cleaned and heated up with a heat gun prior to pressing the pins in.
I took a piece of 1/4" steel plate and made my own 09910-20111 "special tool" for holding the rods.
I then used a piece of threaded rod, made a "T" handle on the end w/ some of it, added a couple washers & nuts and used it to draw the pins through the pistons. There's an arrow on the face of the piston, make sure it points toward the front tire.
Pretty slick.

Same tool, combined with a 4" piece of 3/4" ID steel tube made a great wrist pin puller (draws the pin through the piston).
(can be seen in the upper left of the picture below from prior...)

All the below parts were lubricated prior to assembly with 2 cycle oil.
The rings were then installed with on the pistons.
There's a "T" stamped in the rings (indicating TOP or facing UP).

The gaskets are ready and tomorrow I'll be slipping them up into the jugs.

[tz375]

Good DIY pin puller. They are rarely needed though if the piston has been heated.

BTW, the pit marks in that pin and bearing are probably corrosion and that's what you're hearing in that big end or main bearing. I'm sure that many bikes have some corrosion in the bottom end, but we don't know it's there until/unless we strip the crank. It's a matter of time before it fails, but it will be interesting to see how long that runs for before it becomes a problem.

[imquattro]

So prior to installing the cylinders, I took the oil injection lines, blew them out, verified the check valves all worked properly. I then polished up the banjo's, cleaned the bolts, and installed them.
As per the workshop manual, thread sealant was applied to the threads prior to installing them.



I cleaned up the oil pump, installed the drive dowel (pictured in the hole at the time, but later removed and installed in the pump), seated the o-rings into the line assembly and tightened it down after clocking it to the drive gear.


Using the rod/piston locking tool: I then lubed & located the rings with their gaps over their pins and lubed the piston & cylinder walls. Dropping the cylinders down over the piston while using my fingers to squeeze the rings was simple task.
The cylinders slid slickly down over the pistons.
I did the Left, the Center, then the Right.
After taking this picture, I realized that I had installed the Right cylinder in the middle! DOH, pulled it off, and installed the CORRECT Center cylinder in its place and THEN the Right jug.
Just grabbed them out of order....

Tomorrow I'll torque the cylinders down.
The engine turns very easily within the cylinders.

[Joiseygirl]

The detail you guys put into your projects, never fails to amaze me.
Wish I were in your class.

[tz375]

Did you fill the oil lines before fitting the oil pump? And when the oil tank is filled, bleed the pump.

[imquattro]

Did you fill the oil lines before fitting the oil pump?

No, I didn't, I did read that in the manual, but did not have the device necessary to supply the pressurized oil into the lines.
I will have to prime it manually. Thanks for the reminder on the bleed.

[cruisingram]

After being educated about the oiling system of the two smokers here, I am highly impressed at the engineering.

[Suzukidave]

Did you fill the oil lines before fitting the oil pump?

No, I didn't, I did read that in the manual, but did not have the device necessary to supply the pressurized oil into the lines.
I will have to prime it manually. Thanks for the reminder on the bleed.

It really doesnt take anything fancy to fill the injector lines .. a oil can with a pump or a turkey injector does the job quickly . It really needs to be done before you start the engine as it could take a good several mins for the lines to fill with the pump . BTW .. your doing a great job on your build

[imquattro]

I'll try the "oil can" technique. It doesnt take anything to pull the pump to get to the ports.
Thanks for the tip!

[Suzukidave]

I picked up a couple of these pretty cheap at the supermarket and they work great for filling the injector lines ( without useing the needle of course )