$270 '78 GS1000EC Project (Frankenstien Re-build)

[rustybronco]

Definitely starting on the seat pan this week, and possibly physically committing to repair the crack in the case with JB-weld. I am 80% certain the JB will fix the leak and hold long enough for me to prepare for a rebuild, but that 20% uncertainty has kept me from actually doing it...

I once repaired a hole on chainsaw crankcase which had a rod bolt go through it. I used a product that was very similar to JB weld. (Ford two part metallic plastic)

the repair outlasted the engine...

[Mr.Midas]

Only made a little progress over the past week/weekend. Was pulling long work hours most of the week and unfortunately caught a cold Thursday. Also had some welcome family visiting through the weekend.

The right switch box, throttle, grip and cables are reassembled and lubed. Still need a couple things before all the forward controls are ready to mount on the bar(haven't touched the MC yet).

I figured doing these few little things while I played with the seat pan plug was the best use of time. And I know once the motor is back in the frame, every day spent on finishing the little stuff will be torture!

Finally, the seat pan plug is ready for waxing, I think...



I hope all that time spent shaping the foam, plastering, sanding, priming, more sanding, painting, and more sanding and painting won't go to waste once the fiberglassing begins.

Only wax I have on hand is the cheap Turtlewax in the green tub. Need to see what the local Ace or Home Depot has to offer. Don't think I'll find anyone around here who sells mold or parting wax off the shelf...

[Mr.Midas]

Found this cool mod while doing some unrelated searching... http://www.thegsresources.com/_forum...d.php?t=135697

The amount of knowledge and ingenuity archived on this site is a testament to the dedication of the all the GS enthusiasts who have shared so much of their time and efforts to provide such a valuable resource to the less experienced(like me). I have been able to find so many answers and good ideas here!

Learning new tricks is awesome!

[Mr.Midas]

I was going to update last night, but was diverted by the welcome news report and subsequent Presidential address... so glad that that infamous terrorist is now history, and special thanks to the dedication and hard work of our military/spec ops/intelligence people!



Friday I finally began laying up fiberglass on the seat pan plug. To prep the plug, I settled on a few layers of an acrylic floor finish which I got free from my bro, and then two coats of turtle wax, leaving the second coat unbuffed. Also ran a strip of masking tap along the bottom edges to help with separation later on.

I have 3 layers so far, woven glass on the outer layers and spun glass in the middle. I did the first layer myself and almost screwed the whole thing up. Even with all my pieces pre-cut and ready to go, I struggled to keep up with the pot life of the batches of resin I had going. Guess 80+ deg weather isn't the best for doing this kind of work.

I let the first layer cure out and then cleaned it up with a sanding disc and 60-80 grit paper, and then prepped for the second layer(the spun matting).
Luckily, I was able to acquire an assistant for the next to layers and things went much better. My helper mixed small(2-3 Tblsp) batches while I brushed, blotted, and dabbed my way from one end of the seat pan to the other. Every 4-5 batches I cleaned the chip brush I was using with acetone to keep it from stiffening up or leaving gelled resin clumps behind.

Looking much better after the second layer.


Finished up the third layer(with the woven mat), called it a night, and left it to set through Saturday. Then, late last afternoon began the extraction process...







More reinforcing and hardware mounting left to do.

I like how it's looking so far, and now I'm really tempted to mount cafe-style seat cushions on the pan instead of doing a fully upholstered seat. Suggestions welcome!

[Mr.Midas]

Progress: Seatpan reinforced with cord ribbing and additional layer of spun glass; Seat latches set up and studs mounted to pan; Applied another layer of woven glass(that makes 5 layers total + ribbing); Rubber foot pad stand-offs glassed in; And foam seat-cushion layered up using neoprene and rebond foam... Just about ready for upholstery!




To make the spun mat conform better to the 1/4" cord ribbing, I lined the pan with some .7mil plastic after working the resin in and filled it up with water(notice the reflection from the water's surface).




Just realized I don't have pics of the latch mechanisms.
For the front latch I used a passenger release mechanism from a Suzuki
RF600 @ $6. The rear latch was fabbed up from scratch.

[Mista M]

That looks great. Just cameacross your build and love the way your going and the budget.
Next time you glass in high temps,keep a bucket of ice nearby. Mix up your small batch and keep it on ice as you work. Slows the kick time down nicely.

[Nessism]

Very impressive craftsmanship Mr. M. Can't wait to see more. Work faster damnit!

Regarding the oil pump gears...good question. I'm inclined to say it's a good idea but I've also heard of people getting oil leaks with the gears too. Think I'd try it but know that you may wind up having to do engine gaskets.

[Mr.Midas]

I'll definitely have to try the ice chilling trick next time I glass again. I did notice that the cold water slowed the reaction down, but I never thought of pre-chilling the epoxy resin...



@Nessism,
I want to work faster too! Can't wait to be done with all the messy work. That seatpan was the worst with all the fiberglass dust & bits, resin fumes, foam rubber dust and smoke. Been waiting to seriously clean up the shop once I'm done grinding on stuff... just a little more to get the Bandit swingarm cleaned up and shocks mounted.
Progress *should* quicken as I complete this more challenging stuff and move on to simple prep, paint, and assembly.

I'll have to see if I can find used oil pump drive gears. No way I'll pay what they want for them new. I'm familiar with this style of Mikuni pump(have a very similar one in my car, which I upgraded to a higher displacement pump from a turbo model when I rebuilt the engine). If I can't find the gears, at least I know how to check the original pump(and fix excessive side-clearance if needed)

[Mr.Midas]

Double-checking measurements in fitting the ZRX shocks and Bandit swingarm offset.

I set up a rudimentary string(Spider Wire fishing line) center-line with the frame leveled side-to-side(going off the swingarm pivot). I really wish I had a set of tapered cones and drill-stock that I've seen used to establish the center of the steering stem, but I think it's pretty darn close with the plumb-bob I rigged up instead. It took me a while to get it "just right", and was rechecked several times throughout the process.

So to repeat/clarify, I have a CL string which lines up with the steering stem, front frame cross-brace, and the center of the centered swingarm pivot(which has been leveled side-to-side and agrees with most cross-points checked along the frame rails), along with plumb-bobs dropped from the steering stem and over the sides of each frame rail where the rear cowl/fender mounts. The rear axle bolt was installed without the wheel and torqued to 6-8 ftlbs.

And the swingarm offset is... When checking via center-line: 4.8mm leftward; When checking via plumb-lines off the rear frame rails: 4.4mm leftward. Varying the torque on the axle bolt only changed the swingarm width while the measured offsets remained the same.


From the info I've been able to glean from others the swingarm should only have 4mm of offset, so I'll double check my measurements and setup again to see if I could be off somewhere.

In order to make the shocks have the same inward leaning angle, it appears that I should be able to center the left shock mount and offset the right mount out to correspond with the offset in the left leg of the swingarm(just need to double-check sprocket/chain clearance).

Also, I was under the impression that the shock mounts needed to lean inwards slightly to match the inward leaning angle of the shocks, but with a couple washers on the upper shock studs, it appears that the mounts want to rest flat on the swingarm... Someone said the mounts needed to lean in something like 8deg.

[psyguy]

I really dig how you're using stuff from other bikes and all the fab you're doing yourself, it's really unique! Looking forward to the updates...

[Mr.Midas]

Shop atmosphere last night after re-working the chain buffer with the side-grinder and dremel tool. One less nasty step done!





It's actually kind of ironic how past projects match up to each other in an inverted sense.



When rebuilding my car, I was focused on the internals/drive-train and never changed the exterior's appearance... and I had a complete motorcycle to ride while the car was down.

[psyguy]

that 1st pic above is like from the "Twilight Zone"...

[Mr.Midas]

Quick note on fitting shock mounts to the Bandit swingarm,
I think I finally have a handle on where and how the shock mounts go. Checking and rechecking positions/alignments... I really don't want to redo any welding on the swingarm.

I was mistaken about slanting the mounts inward. Basically, the mounts need to be centered on the weld-line joining the swingarm end to the box tube arm. The ~8deg angle is to match the taper of the cast ends. I've already had the mounts made(without the angle), but I'm sure we'll find a way to make them work without compromising strength. Should have them welded up this weekend at my brother's.

Small diversion:
I liked the Idea of fitting a tire hugger(in case I decide to remove the inner fenders), so, I found a Hugger/chain guard from a 09 Yamaha YZF-R1 @ $18 that looked like it would fit with not to much work... just needed to be narrowed up about an inch.


Cut, sand smooth/flat, rejoin, and burnished the sharp edges.








Looks almost factory made.
It won't mount perfectly centered on the wheel, but I figured if Suzuki engineers could make a swingarm with an offset, then why can't I setup a little fender the same way?

[Mr.Midas]

So the past weeks haven't really gone as planned. Work, family obligations, the holiday weekend(100 mile bicycle ride), more work, and our friend's welder was down for repairs(and now he's out of state for a week)...

Anyway, I did make some progress. Rebuilt the MC, spared a few minutes through the days to work on the seat... just put the finishing touches on the seat cover!



It's a basic semi-flat black marine vinyl remnant which cost about $5(the half-yard of headliner foam I picked up cost me more). I used a trusty old pfaff sewing machine(which belonged to my grandmother) to join the three panels and do a simple top-stitch seam.
I sized my patterns for the panels before adding the last layer of upholstery foam to insure a snug fit.



I think I like the look so far.



I really need to get cracking on this project!

[7981GS]

You do great work! If you weren't so far away, I would be sending a couple of seats your direction.

Daniel