New Guy, New Project: GT550

General discussion about Street two-stroke Suzuki motorcycles.

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jabcb
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Re: New Guy, New Project: GT550

Post by jabcb »

I’m not a fan of the tiny turn signals that are potentially too small for senior-citizen drivers to see.

Just got some K&S LED turn signals that look good.
Available in black, and are DOT / E-mark approved.
http://www.kandstech.com/productreleases/newprod200.pdf

Our GT250 project bike also has a rather meager alternator.
If you don’t mind the $$$, there are some really good LED headlights that draw a lot less current.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
PHPaul
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Re: New Guy, New Project: GT550

Post by PHPaul »

Oh yes, those will do nicely! Thanks!

Edit: Just found prices. GASP! Not in the budget.
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jabcb
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Re: New Guy, New Project: GT550

Post by jabcb »

The good LED headlights are priced high enough for them to be good Christmas gifts.
Gives you a whole year to make gift suggestions.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
PHPaul
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Suzuki 2-Strokes: 1979 Yamaha XS650, 1974 Suzuki GT550
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Re: New Guy, New Project: GT550

Post by PHPaul »

Took the carbs off for the third time today, checked and reset the float height, cleaned some aluminum oxidation out of the bowl on the center carb and rechecked that all the various passages were clear.

Left carb float was off quite a bit, other two were spot on.

Pilot jet on the center carb was questionable (not surprising given the powdery oxidation) but didn't notice anything else.

Put the carbs back on the bike and after some cranking it lit off! With no airbox or filters it doesn't want to idle very well, but I can't see any point in diddling with carb adjustments until my new air box and throttle cables come in.

Nice to know it runs tho!
PHPaul
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Re: New Guy, New Project: GT550

Post by PHPaul »

https://youtu.be/icdlSn5KIJ8

Put the new throttle cables on, adjusted the oil pump, mounted the correct air box and covers with new filters.

Starts and runs much better, still have idle issues.

Assume some of that is from running both premix and oil injection while I'm making sure the OI is working properly. Gunky plugs if nothing else.

Dumped the premix and refilled the temporary tank with straight gas and let it run a bit. Seems to be clearing up, getting a little smoke on decel which makes me think the injection is working.
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Alan H
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Re: New Guy, New Project: GT550

Post by Alan H »

Sounds positive.
I reckon a good run will clear the birds nests then a set of new plugs will do the trick (fingers crossed.)
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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wingrider
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Re: New Guy, New Project: GT550

Post by wingrider »

Sounds pretty good! Will it idle at all, or does it just die off if you let off the throttle?
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Re: New Guy, New Project: GT550

Post by PHPaul »

Pretty much dies unless I adjust the idle up above 1500 RPM.

Winter arrived, so haven't worked on it since the video.

Don't think it's the idle jets, they checked out clean on the third time through the carbs.

Suggestions?
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Alan H
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Re: New Guy, New Project: GT550

Post by Alan H »

Just in case there's an air leak on the inlet side, start the engine and run at tickover, then squirt carb cleaner around the joints between carbs and cylinders. If the engine speeds up, that's where the leak is. Mine did this and all I ended up doing was changing one inlet rubber which wasn't sealing properly due to being hard.

Otherwise if timing is OK and jets clean, then it's just something that we have to put up with on a 40YO+ two stroke.
If it all went perfectly, we'd still think there was something wrong - or about to crap out.
The bike might just need running and get a few miles on, they do respond better to riding than polishing I find.
I expect to have to go through all this when I get mine running.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
PHPaul
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Re: New Guy, New Project: GT550

Post by PHPaul »

I gasped at the price, but I went ahead and forked over for new rubbers between the carbs and engine. The old ones were just problems waiting to happen.

Hadda do that on my Yamaha too.

Never trust a 40 year old rubber... :shock:
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Alan H
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Re: New Guy, New Project: GT550

Post by Alan H »

No babies when we shoot dust my friend.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
GTandcbr
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Re: New Guy, New Project: GT550

Post by GTandcbr »

Paul I'm sure you are aware but the pilot jet has two outlets. One is straight up to the main venturi but it also feeds out to a minute jet in the engine bell mouth easily missed have a look here at fig 2
98 carb Blackbird and GT550j
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Re: New Guy, New Project: GT550

Post by PHPaul »

GTandcbr wrote:Paul I'm sure you are aware but the pilot jet has two outlets. One is straight up to the main venturi but it also feeds out to a minute jet in the engine bell mouth easily missed have a look here at fig 2
Yup, that one has caught me before. I made a nozzle adapter so I could force carb cleaner into the needle seat and then looked for spray to come out both orifices.

Which doesn't necessarily mean that another random speck of crud hasn't floated in from somewhere and undone all my previous work... :roll:
PHPaul
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Re: New Guy, New Project: GT550

Post by PHPaul »

Well, when winter finally showed up, it didn't mess about! WAY too cold to be working in the garage.

March is a fickle b*tch, daughter and I dug out the bikes and went for a ride last weekend, this weekend it's struggling to get out of the 20's again.

Image

Image

My attempt at making/upholstering my own seat was a total failure. Really, REALLY bad. Put the oooo in oogly.

So I sprung for the Hotwings Glass seat and pad that another member posted a picture of. I really liked the look, just didn't want to spend the money. Glad I did now.

Had to reconfigure the tail light mount which left me with three extra holes in the rear fender, I'll have to figure a way to fix that too. Overall, I'm very happy.

The seat base will be painted to match the rest of the bike as soon as the weather warms up enough, then I'll hit all the color with a coat of fuel resistant 2-part clear coat.
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Alan H
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Re: New Guy, New Project: GT550

Post by Alan H »

I notice that the silencers are on the outside of the rear footrest hanger, this makes the exhaust very wide as they are normally on the inside of the hanger. Can also cause leaks out of the crossover joints on the downpipes.
Your choice if that's what you prefer, but just commenting.
Some nice mods there, that seat unit is very tidy and the rear shocks too.
I take it that the 20 that you refer to is 20 degrees F, I'm just back from Australia/NZ and VietNam where we had a high of about 38C - about 100F. Humid and just too hot. Had to drink lots of beer to keep hydrated and survive. Oh dear!!!
Back home now to about 5 degrees C, just over 40F. Brrrr!
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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