Suzuki 2 Strokes

So a couple on here have seen the newest project that I added to my garage. A very rough version of the 1974 Suzuki GT550L.

I had very little information about the bike when I purchased it because I was not in the country at the time of purchase. I saw a couple photos online from a guy trying to sell it locally and contacted him on the last day that he still had the place this bike was sitting at. After looking over the photos and asking a couple questions I decided to buy it. The main reason I pulled the trigger so blindly, well, he sold the entire thing to me for $100 to get rid of it. Figured that if the engine was shot, I could salvage some of the parts and at least make my money back off it so I wasn't out anything. A couple friends that were home ended up picking it up for me and storing it until I returned.

So yeah, that's the oh-so dramatic story of how this thing fell in my lap.

My wife had a friend over so I was able to hide in the garage for a little bit. Tore the intake off the bike and removed the carburetors.


They aren't as gunked up as I had initially expected. Going to clean them up and I have a carb rebuild kit on the way. Plan to just replace the air intake setup with a set of 3 cone filters so I don't have to find all the parts that are missing with this. Plus, I like the look a little better.




I have already found that I need to replace the fuel cock, the grips, the throttle/switch combo, new battery, tires and possibly the rear shocks. Not a lot that is actually missing on this thing that I shouldn't be able to do myself. After I finish the carbs, I will probably open up the engine to see what's in there...

I do need to invest in something to get these parts clean. Until then, metal brush to the rescue...

Was able to get some work done last night. Did a little more paint stripping on the tank, vacuumed out the gunk and dirt that was on top of the engine, tore off the grips to find out that I need a new throttle due to it cracking. I also have the carbs about 99.9% assembled. I ended up misplacing one of the valve nut/boot combos and need to find it or replace it. It SHOULD be somewhere around the garage, but who the hell knows at this point. I have to keep searching. Everything is freed up and cycling smoothly like it should.




Ran a compression test on the 3 cylinders and got some decent numbers from what I have researched.





And finally, with the bike pulled out, I hooked up a battery just to see what I was dealing with. It will sputter and try to start. I get air movement from all the mufflers and can feel air being moved at the intakes. Right now, I'm thinking that once I get the carbs assembled, I can replace the spark plugs (seriously need those) and put some oil in it, get some gas and it just may start and run. Then I'll just have to do some timing on the carbs and it should be good.

And if it isn't obvious, I am not a mechanic. I also know very little about bikes other than how to ride them and put gas in them. This is a whole new world for me, so please point out if I should be doing something or if I'm making a bonehead mistake with rebuilding this...

Anyone who restores old bikes, cars or whatever must be sligbtly 'strange' at least.
What sensible person would spend days of their time and loads of money to get something almost belonging in a museum to a state where it would be used as (hopefully) regular transport when they could just buy a modern soulless machine far more reliable?
Anyone who likes being an individual, that's who.
We've all made mistakes with these old bikes and probably will make more, but not to worry - we enjoy it.
Ask your questions and someone will help. That's why forae like this are here.
Then ride it and enjoy something that YOU have put your stamp on.

As for parts going missing, well that's tbe f***-up fairy who lives in every garage where an old bike or car is kept and worked on. She (it must be a 'she') moves things that have just been put down but no-one ever sees her.
You'll find that carb rubber in a box or drawer that hasn't been used for months. Then listen for the faint laugh, it sounds a lot like a breath of wind.
Tell us when you do, but as I hear it a lot here, she may have moved in permanent, the witch!!

I hate to cause you to back track on work done , but i didnt see in the carb picture where you pulled and cleaned the emulsion tubes . Any time you see the crud in the float bowl chances are these also need pulling and cleaning .

Love it Allan h, and yes I found it. Silly little thing fell into a tool drawer...

Suzukidave... Now I have to look up emulsion tube. Still learning what parts are called.

Also known as a needle jet.... http://www.oldjapanesebikes.com/mraxl_G ... /index.php" onclick="window.open(this.href);return false;

Alan H wrote: As for parts going missing, well that's tbe f***-up fairy !

Mine are more like Gremlins .. i can put down a tool or part and be damned by the time i look back it will be gone . Seems they watch how much beer i drink while i work as the more i drink the more they F@&k with me

Suzukidave wrote:Also known as a needle jet.... http://www.oldjapanesebikes.com/mraxl_G ... /index.php" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

Ah yes, I changed out all the jets and pilots and screws. Thought maybe there was a part that I missed. Good looking out though. Thought I missed something there for a second.

Are you telling me that motor wasn't stuck after sitting for who knows how many years outside... And my 76 GT750 that did sit (but in a climate controlled garage for a decade) was so frozen that after buying a special puller then heating/soaking /swearing and pounding and FINALLY a porta-power WHICH snapped 2 of the 3 pistons in half before it finally let go...
I give up...

Cool project. keep us posted on the progress!

I'm not saying anything about the parts not being stuck. I have no clue that they are free without opening the engine up...

However, my common sense is kicking in with this recent "start test" since I didn't hear anything nasty as well as felt air movement at both the intakes and pipes and hoping/thinking that everything is moving... Might have to put that common sense back in my pocket though.

blurred wrote:

Suzukidave wrote:Also known as a needle jet.... http://www.oldjapanesebikes.com/mraxl_G ... /index.php" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

Ah yes, I changed out all the jets and pilots and screws. Thought maybe there was a part that I missed. Good looking out though. Thought I missed something there for a second.

Did you use the jets that came in the rebuild kits? If so, what size mains came with the kits? GT550 uses a 1/2 size smaller jet in the center cylinder, and some kits don't come with the correct size jets to begin with.



Other than that, great score for $100.00. I bought a roached out '72 GT550, discovered that it was completely past it's use by date and after I pulled some parts to fix up my '73 I sold the rest for $500.

jeff g wrote:

blurred wrote:

Suzukidave wrote:Also known as a needle jet.... http://www.oldjapanesebikes.com/mraxl_G ... /index.php" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

Ah yes, I changed out all the jets and pilots and screws. Thought maybe there was a part that I missed. Good looking out though. Thought I missed something there for a second.

Did you use the jets that came in the rebuild kits? If so, what size mains came with the kits? GT550 uses a 1/2 size smaller jet in the center cylinder, and some kits don't come with the correct size jets to begin with.



Other than that, great score for $100.00. I bought a roached out '72 GT550, discovered that it was completely past it's use by date and after I pulled some parts to fix up my '73 I sold the rest for $500.

Wasn't aware of the center being different. I see the numbers, but don't know how to measure them... off to do some googling. Appreciate the info!

blurred wrote: Wasn't aware of the center being different. I see the numbers, but don't know how to measure them... off to do some googling. Appreciate the info!

The jets are marked with the size. If the jet is marked 97.5, then it's a 97.5. 1/2 size down is 95. If your eyes are like mine, break out the magnifying glass. My recommendation is to use genuine Mikuni jets. You need the Large Round style and you can order them from any good bike shop, but you might have to buy the whole 4 pack and with the GT550, you might end up with 8 jets when you need 3. But, it's good insurance using Mikuni jets instead of Keyster. You could always check here, though, as someone might have the 3 jets you need. If you need pilot jets, bring one of the originals to match with the picture in the Parts Unlimited catalog...I don't remember the style number off the top of my head.

Jeff