GT550 - new member + questions

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tz375
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Re: GT550 - new member + questions

Post by tz375 »

Orstralia mate. :wink:
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Re: GT550 - new member + questions

Post by ConnerVT »

arneg
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Re: GT550 - new member + questions

Post by arneg »

So I finally got around to putting the Jemcos on. Sound great... but after only a few blocks the gearbox locked up. It sounded like the starter clutch is busted... but I have no clue. In neutral I can't move the kickstart lever - even with the clutch pulled.

Any advice?

http://www.youtube.com/watch?v=ZjUY8JSQzlo" onclick="window.open(this.href);return false;
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Alan H
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Re: GT550 - new member + questions

Post by Alan H »

Take the clutch off and check the starter clutch behind. I had a bike with the early clutch back in '72 and never had a problem with it - I did keep it clean, tight and lubricated though on a regular basis.
The later clutch will exchange with the early one - but as a complete unit, not just the starter clutch part.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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Re: GT550 - new member + questions

Post by arneg »

Alan thanks. I got a full clutch with starter clutch. Also got a new set of carbs (2nd try!). I hope the seals will still be good and the bike will be good after that is done.
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Alan H
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Re: GT550 - new member + questions

Post by Alan H »

Make sure there are no notches or ridges on the clutch basket or the clutch will grab.
If they are like the pic, GENTLE filing will smooth the basket, but if they are too bad, then the clutch will bang when you change gear as the plates go back and forward in the grooves.
I would say that the PO was very heavy with the clutch and liked fast starts and fast changes!!
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Think of how stupid the average person is, then realise that half of them are more stupid than that.
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Re: GT550 - new member + questions

Post by arneg »

Thanks again for the tips. Didn't get very far today as my largest socket wasn't large enough for the clutch nut. What size is it? 34mm?

But I did find the reason for failure, and am happy that I guessed right:

Toothing like a 5-year old.

Image

And this:

Image

I hope there's no more damage than that in there.
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Re: GT550 - new member + questions

Post by Coyote »

typical early model exploded starter clutch. They all do it eventually. Let us know what else you find. Pics are great!
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arneg
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Re: GT550 - new member + questions

Post by arneg »

So today I finally got around to inspecting what's on. Note to self: needed a 32 size socket to open the clutch nut.

Everything came apart easily but the starter mechanism was kinda fried on.

Image

Had to use this 3-claw extractor to get it off.

Image

So the thing cracked at the neck. At the same time the smaller starter cog had come undone and dropped the shoulder pin into the case.

Image

Collected quite some loose pieces of scrap from the engine.

Tomorrow I'll be replacing the carbs (anyone have a starting point for standard with Jemcos?) and hopefully give it a nice go!
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Re: GT550 - new member + questions

Post by Allan k »

Alan H wrote:Make sure there are no notches or ridges on the clutch basket or the clutch will grab.
If they are like the pic, GENTLE filing will smooth the basket, but if they are too bad, then the clutch will bang when you change gear as the plates go back and forward in the grooves.
I would say that the PO was very heavy with the clutch and liked fast starts and fast changes!!

Would you say that this clutch has been 'abused', or had a bit of quickie gearchanges/starts?
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Re: GT550 - new member + questions

Post by jabcb »

Coyote wrote:typical early model exploded starter clutch. They all do it eventually. Let us know what else you find. Pics are great!
The clutch update is covered in service bulletin GT-26
http://www.ozebook.com/compendium/techb ... 022-26.pdf
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Re: GT550 - new member + questions

Post by Alan H »

That looks like it has been run without oil. No wonder it seized.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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Re: GT550 - new member + questions

Post by arneg »

don't know... 1,500ccs of oil came out of it. anyway, she's a runner now and great fun. starts first kick, idles well. just need the temps to get back up in the 60s now! also just figured out that the fueltap doesn't have a close position! crazy stuff.
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Re: GT550 - new member + questions

Post by Alan H »

It doesn't need one as it's a diaphragm tap.
The three positions are 'on', 'reserve' and 'prime'.
You'll only need prime if the bike has been stood for a few days.
When the engine runs, impulses from the crankcase via the pipe at the back of the tap allow fuel to flow to the carbs. If the carbs are empty (not been run for quite a time) you'll have to use prime as it will take a helluva lot of kicking before enough fuel gets to the carbs to allow a start.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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Re: GT550 - new member + questions

Post by Cragdog »

arneg wrote:don't know... 1,500ccs of oil came out of it. anyway, she's a runner now and great fun. starts first kick, idles well. just need the temps to get back up in the 60s now! also just figured out that the fueltap doesn't have a close position! crazy stuff.
Do you have the new carbs and Jemco's on? Love the sound those pipes make. Let's see some pics of the finished product. :lol:
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