GT550A carburettor setup

Johninreading
Posts: 18
Joined: Sun Feb 17, 2019 9:49 pm

GT550A carburettor setup

Post by Johninreading »

I have rebuilt a set of old carbs: ultrasonic clean, new bellows, boots and fitted a carb refurb kit (gaskets , needles and jets). The main jets supplied are marked 98 but both my old carbs and the ones I bought to refurb we’re fitted with 102.5 so have rebuilt using these.

I’ve checked float height (24.5mm). Now I need to set slide heights and mixture screws. My Haynes manual only has instructions for old triple cable carbs. Anyone have a link to a setup guide for the later A/B throttle body model.

Thanks
John
barney01
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Re: GT550A carburettor setup

Post by barney01 »

NO SMOKE .......NO POKE
teazer
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Re: GT550A carburettor setup

Post by teazer »

Try not to use old jets unless you know their history. Too many people poke thinks into holes they were never meant to go into.

And if possible, set the FUEL level while the crabs are on the bench
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mizzytheman
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Re: GT550A carburettor setup

Post by mizzytheman »

teazer wrote:Try not to use old jets unless you know their history. Too many people poke thinks into holes they were never meant to go into.

And if possible, set the FUEL level while the crabs are on the bench
It’s probably better to use another bench that doesn’t have crabs. :roll:
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canaletto5
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Re: GT550A carburettor setup

Post by canaletto5 »

These are not to be confused with crabs on the beach. Beach crabs just nip your toes but bench crabs walk off with the components of your carburetor. The only way to stop them is to smear blue grease everywhere ;)
barney01
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Re: GT550A carburettor setup

Post by barney01 »

:P :P :P
NO SMOKE .......NO POKE
wardy
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Re: GT550A carburettor setup

Post by wardy »

canaletto5 wrote:These are not to be confused with crabs on the beach. Beach crabs just nip your toes but bench crabs walk off with the components of your carburetor. The only way to stop them is to smear blue grease everywhere ;)
Does this include all Shell fish that I may keep in my workshop or just crabs.
Presumably fresh water crabs behave in the same way as salt water ones.
I've had similar issues with whelks, mussels and shrimps so I now keep them away from my bench top and and motorcycle related items.
The two just don't mix... it's not worth it.
Andy;
1976 gt750A; 86 FZ750
1977gt380A
1982 z400j
1981 z650f.....1988 Sufolk punch 14"
"look;it's my bike; when you own it ,you can paint it any colour you like!"
(I once painted my Z650 PINK and had the pink panther logo on the tailpiece)
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mizzytheman
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Re: GT550A carburettor setup

Post by mizzytheman »

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Johninreading
Posts: 18
Joined: Sun Feb 17, 2019 9:49 pm

Re: GT550A carburettor setup

Post by Johninreading »

So, all back together with 102.5 main jets. Followed set up exactly as described in link (thanks for that). Good news, started on choke first prod and ticks over like a Swiss watch. Revs to about mid revs very well, but gets really lumpy above about 3000. Now the bad news, pulling away, engine is really lumpy and will not rev smoothly. I didn’t understand the synchronisation steps (the bit about disconnecting the plus one at time) but maybe Sync is the cause of my issue). Going to read through the instructions all over again. Question, to get at the throttle valve adjusters I’m gonna have to remove the tank and tune it with what’l fuel is in the float bowls. Is that the right way to do it?
barney01
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Re: GT550A carburettor setup

Post by barney01 »

Best way to balance the carbs is with an airflow meter just need to take the airbox off
NO SMOKE .......NO POKE
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