New Guy, New Project: GT550

[PHPaul]

Thanks for the tip on the exhaust, I thought something was wonky but I couldn't spot it.

I'll fix that!

And yeah, 20°F or about -7° C.

And a LOVELY breeze to go with it...

[PHPaul]

MUCH better, don'tcha think?

Doh...

[jabcb]

I like how you cut down the Hotwing seat a bit so that you could lower it.
Is that the Dark Wing or Dark Wing 2 seat?

[PHPaul]

Dark Wing II.

The mounting worked out quite well I think. Just welded a piece of 2" flat stock across the top rails between the back of the tank and the front of the battery box. I bent the outer 1/2 inch of each side of the flat stock to raise it slightly above the plane of the frame rails. Had to cut a little half-moon out of it in the center for access to the front battery box bolt. There's a tongue bolted to the front of the seat pan that slips under the piece I welded on.

The notches on the side allowed it to sit down far enough that I could use the upper shock mount bolts as the rear mounts.

The tail light/license plate holder is a unit I got off Amazon, had to very slightly notch the tail of the seat to clear the housing on that.

I may find a suitable piece of rubber or very dense foam to put between the rear fender brace and the bottom of the seat pan just to help support my fat arse. Don't wanna crack the fiberglass...

[Alan H]

MUCH better, don'tcha think?

A lot neater and takes less room in the garage too.

[jabcb]

The installation video on the Hotwing website has his installs with very little support.

RedZone has an early Dark Wing seat & is mounted similar to yours, except brackets were welded to the frame for the rear bolts. That setup has worked out just fine.


DimeCity sells a kit for no-weld installs of cafe/tracker seats.
I used the kit for the test fit of the Dark Wing seat on the 72 GT550 project.
viewtopic.php?f=21&t=12060

The kit parts are HDPE plastic. Grainger sells sheets of the plastic.
Haven’t fully worked out the details, but I’m going to attach an HDPE sheet to the frame & then attach the seat to that.

But rats, its currently snowing & I have to deal with the title problems first.

[PHPaul]

Well, fudge. Drat. Shucky-darn. Poopoocaca. Rats...

Had (I thought) all the parts to get the Suzuki on the road. Got the tins all clearcoated without wrinkling the color coat or poisoning myself with the SprayMax 2K. Let that all harden up for a few days. Reassembled the petcock after blocking off the reserve port so I'd have an "off" position and disabled the vaccuum function. Put the petcock and new gas cap on the tank, mounted the seat to the seat base. UPS delivered my pieces parts from McMaster-Carr to build a nice Tygon fuel line with an in-line filter. Small, neat, tucks in out of the way.

First issue: Front brake went away while sitting. Re-bled it, good. Might have to get into that caliper again, but for now it'll do while I prove the rest of the bike is working.

Second issue: Found out why they'd butchered the original battery box: Rather than bother to get the right battery, they just made it fit. So of course the battery I had for it won't fit in the NOS battery box. Ah, well, I can steal the one out of the Yamaha long enough to test drive it. I'll go get the right baddry tomorrow.

Put the tank on, put the side covers on, put the battery in, put the seat on, veeerrrry carefully poured some gas in the tank.

Why is my foot getting wet?

Oh. Because the )#($ing petcock is leaking like a sieve. crap.

The search function eventually led me to Parts N More and their adapter plate and standard On/Off petcock. Adapter, petcock and shipping $50. MUCH better. Of course, now I wait several more days for stuff to arrive.

Just as well, while I'm waiting I can scrounge up the proper size of push-nuts to hold the emblems on the side covers and fab up a knob for the left side which is missing.

Soon...

[Alan H]

You didn't expect it all to go right first time didya?

If it did, everyone would have a 70s bike!

It'll come right.

[PHPaul]

Well, in spite of years of experience, I HAD hoped... I had a mental image of me riding it up and down the driveway like a 15 year old with a new scooter and no license.

I've been a very good boy, patience-wise and patience is NOT one of my virtues.

Standard mantra for these old gals tho: "Couple more days, couple more bucks..."

[Alan H]

Well, in spite of years of experience, I HAD hoped... I had a mental image of me riding it up and down the driveway like a 15 year old with a new scooter and no license.

I've been a very good boy, patience-wise and patience is NOT one of my virtues.

Standard mantra for these old gals tho: "Couple more days, couple more bucks..."

You're catching on my friend!

[PHPaul]

Okay, NOW it's alive!

Got the adapter and petcock in from Parts N More and got them fitted.

Got the tank, sidecovers and seat back on and diddled around getting it started.

Went for a short blast and it runs quite well indeed under a load and full throttle. Not as pipey as I remember my RD being, but the power curve is definitely noticeable.

Realized I'd forgotten to mount the mirrors so returned to the shop and did that, then rode over to the gas station to fill up. Handles quite well with the All Balls bearings in the neck and the Cheapo Chinese shocks on the back. The forks need a bit of attention, I'll start with a bit more oil and/or maybe a bit of preload on the springs.

Couple of details to finish up, tank badges and a front fender.

Three mechanical issues of varying significance:

1. It wants to dump gas out the carb overflows if you don't turn the gas off when not running. Might need to look at the floats again.

2. One cylinder wants to cut out at cruise/partial throttle/light load. IIRC this is something of a "feature" of multi-cylinder two strokes, but I'll look into carb settings, points condition and plug color.

3. After riding 5-6 miles and getting it good and warm, it now wants to rev to the moon in neutral more-or-less randomly. It is NOT linkage related, carb arms are closing all the way. I'm thinking air leak somewhere. I'm PRAYING it's not crankshaft seals.

Advice on where to look for this issue would be appreciated.

[GTandcbr]

2 and 3 could be a sticking choke piston. Causes cylinder to stop firing too much fuel and then high revving at idle.

[PHPaul]

2 and 3 could be a sticking choke piston. Causes cylinder to stop firing too much fuel and then high revving at idle.

That could very well be, the choke was being a bit funky. I'll check that and report back.

[Alan H]

Three mechanical issues of varying significance:

1. It wants to dump gas out the carb overflows if you don't turn the gas off when not running. Might need to look at the floats again.

Normally this is either slightly high fuel levels in the floatbowls or the float needles aren't seating properly, either worn needles or worn seats where the needle sits. Hopefully the floats aren't repaired with solder as that can make them heavy and cause issues too.

2. One cylinder wants to cut out at cruise/partial throttle/light load. IIRC this is something of a "feature" of multi-cylinder two strokes, but I'll look into carb settings, points condition and plug color.

I had this one on the 550K (separate carbs) and it was a part blocked slow running jet. Runs OK cold with choke on, but set off and lose one pot until about 3500rpm or so then it comes back in. I put up with it for a time, but recently stripped all the carbs and blew everything through - found a long thin 'turd' for want of a better description partially blocking the tiny jet. Cleared and runs fine now.

3. After riding 5-6 miles and getting it good and warm, it now wants to rev to the moon in neutral more-or-less randomly. It is NOT linkage related, carb arms are closing all the way. I'm thinking air leak somewhere. I'm PRAYING it's not crankshaft seals.

I've got this on the 550A that I'm doing and it's a slightly sticky carb cable that 'just' holds all 3 carbs open a tad. I've ordered a cable oiler to oil the cables and hopefully this will be cured when I can get back in the garage. The carbs only have to be open a few thou extra to increase the revs at 'tickover'. If it does it at home, try and push the top linkage 'butterfly' down and see if it slows the engine. Have you greased the top bar linkage across the carbs? When it gets warm, it may just bind too.

If you want to test for an air leak, just spray some carb cleaner around the intakes and if the revs lift, there's the leak.

[PHPaul]

Alan, thanks for all the leads.

1. Yes, I suspect float levels are at issue here. I put kits in the carbs that included new needles and seats so that's less likely to be the issue but still possible I suppose.

2. ANY amount of throttle will put all three cylinders back on line. It's only at trailing or neutral throttle that the cylinder drops out intermittently. When I take the carbs off to reset the float levels I will go through the cleaning process again.

3. First thing I thought was hanging linkage, or that the idle stop on the shaft was set too high when the engine was first started after sitting for who knows how many years and cleaned up after a good run.

Not so, there is actually a gap between the cable quadrant and the stop. I suppose it IS possible that the individual slide height adjustments are off and they will be rechecked as well. The throttle linkage shaft and bushings were thoroughly cleaned and lubed when the carbs were reassembled.