New here with a gt550

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rubbersdown550
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Suzuki 2-Strokes: gt550

New here with a gt550

Post by rubbersdown550 »

Hi guys, new here. Was directed this way from my usual stomping grounds the customfighters forum after asking some questions about a gt550 i just acquired.
Frame numbers put it as the 61st one off the line in 1973. It has the older style carbs with the tall screw on round caps. Is there anywhere to get a rebuild kit for these? Everywhere I have looked only has the 74+ kits for the newer style carbs. Any benefit in buying and running the later style carbs?
Thanks guys, more questions and build pics coming in the near future im sure.
Cody Miller.
GTandcbr
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Suzuki 2-Strokes: suzuki gt 550j
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Re: New here with a gt550

Post by GTandcbr »

Hi and welcome to the forum. First let me give you a link to our bible
https://www.oldjapanesebikes.com//mraxl ... /index.php" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;
You will find information galore on there about the different carbs.
IMHO i have had both types of carbs, seperate and gang, i prefer the seperate as they are easier to adjust.
There are several suppliers of kits to refurb carbs. I always stick with Mikuni genuine stuff as i have had poor results from aftermarket. There are suppliers this side of the pond but I'm hoping someone over your side will have a more local store.
Good luck!
Another useful link for you http://www.3cyl.com/mraxl/gt/manuals/gt ... ntents.htm" onclick="window.open(this.href);return false;
98 carb Blackbird and GT550j
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Alan H
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Suzuki 2-Strokes: 4 x GT550s - J, M, A, B.
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Re: New here with a gt550

Post by Alan H »

The early carbs are easier to service and adjust.
You can't easily fit later carbs as the barrels and head are different, also the tap position on the tank changed so you'd need the later tank. Just strip and clean the carbs and leave everything oem.
Carb refurb kits jets are pants unless you get genuine mikuni.
I've just sold a '73 K 550 and the carbs weren't perfect, but still worked fine after ultrasonic cleaning - don't ultrasonic more than 15 minutes or they'll pit and carb bodies are like rocking horse crap.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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jabcb
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Re: New here with a gt550

Post by jabcb »

What are you doing for the air filter & pipes?
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
rubbersdown550
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Suzuki 2-Strokes: gt550

Re: New here with a gt550

Post by rubbersdown550 »

Thanks for the reply guys. I am mainly looking for the gaskets, not so much jets and things like that. I work at a restoration shop and we also do vapor blasting and I have an ultrasonic cleaner so cleaning them is not a problem. Air filters I was thinking just using some uni foam filter pods and for my exhaust I am leaning towards using a set of Jemco pipes as I like the look of them. Any opinions are well appreciated as the GT series of bikes is new to me. Just delving into this bike, I will have a read thru the "bible" you posted for me and the other links you supplied jabcb, thanks for that.
GTandcbr
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Suzuki 2-Strokes: suzuki gt 550j
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Re: New here with a gt550

Post by GTandcbr »

Just one observation about fitting pods. It has been identified as a problem that because they aren't supported at the back it can cause them to leak , through engine vibration,,causing the motor to run lean. Just sayin'
For your gasket http://www.partzilla.com/parts/detail/s ... 11010.html" onclick="window.open(this.href);return false;
98 carb Blackbird and GT550j
rubbersdown550
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Suzuki 2-Strokes: gt550

Re: New here with a gt550

Post by rubbersdown550 »

Thanks for the tip and the link!
Stev-o
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Re: New here with a gt550

Post by Stev-o »

Congrats. Got pics? I would like to find one....
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Re: New here with a gt550

Post by Vintageman »

The hard thing to find about the early carbs is the the Needle Jet. I have a 3-4 or sets of the early carbs and none of the Needle Jets survived (my standards). Then by miracle someone on eBay posted some. All gone now and first time in 8 years I saw any show up.

These are several steps larger at "P4"
http://www.ebay.com/itm/Suzuki-1977-GT5 ... vw&vxp=mtr" onclick="window.open(this.href);return false;.


There is a standard size hand reameer that makes them about an O-9. That worked OK for me... O-6 is what I run/found all the carbs I have had O-5 from factory

The later carbs you can cross to other Mic needle jets i think. I have not found a cross for the early carb , but would keep looking if I still needed too. They are short buggers and was thinking of getting longer ones and having the bottom half machined up to fit or something like that

To qualify condition of a need jet you have to check the machine surface where the needle enters then inside (critical) the barrel for a few mm where the surface needs to be smooth and inside diameter precise for this is how the fuel is metered about the male :wth: jet needle. The outside of needle jet condition means nothing.

The needle jet is not important if you only idle and drive WOT the other 90% in-between relies on a good needle jet. Yes jet needle must be good to.

Good luck
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76 GT250 (T350 upgrade),
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