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GSX750ES REVS SUPER HIGH AVTER INSTALLING CARBS


SATANSAM

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I bought a rebuild kit for my gs1000 carbs (BS type) and the needle and seat is confusing me.  The old needle was held into the seat with a tiny tiny spring. The New needle appears to not have any way to keep it seated in the seat.  Are they supposed to just hang down on the float tang until the bowls fill and push them up into the seat?  Or is there a part in my kit that holds it in???  

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Edited by RickLee
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The reason I ask Satan Sam is because I wonder if you installed a needle and seat like this with nothing holding the needle in place ( in its seat ). Or is that how it’s done with the rebuild kits?   I notice also that this seat has a screen filter apparently taped onto the underside as opposed to the plastic filter in the originals seat.   Could be we just bought kits that don’t or wont work.

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7 hours ago, RickLee said:

Are they supposed to just hang down on the float tang until the bowls fill and push them up into the seat? 

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Correct! And in case you don't know, apply a thin layer of grease on the valve Oring before fitting it in the carb;)Man, I'm so posed to be the one with doubts here! :D

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8 hours ago, RickLee said:

The reason I ask Satan Sam is because I wonder if you installed a needle and seat like this with nothing holding the needle in place ( in its seat ). Or is that how it’s done with the rebuild kits?   I notice also that this seat has a screen filter apparently taped onto the underside as opposed to the plastic filter in the originals seat.   Could be we just bought kits that don’t or wont work.

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Is that a chinese cheap kit? I've seen friends using them but they often don't stick to the specs from the dealer...I'm no expert, that's why I've got a 12 page topic! But I don't like the look of that screen filter...HAve a look and see if you can match original plastic filters on them. A part from that, needle must simply be put in the valve and will be basically always be in touch with the fliat "tounge" 

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I know I'm a pain in the arse...But I started the bitch this morning, starts easy and revs are OK cold (dies slowly if choke not used and it's very warm here in Spain), ...Revs go straight down when blimp't the throttle with cold motor...It's when warm when she fckn hangs specially when throttle blimped...At least it's better than before...I wanted to buy the airbox boots but out of stock...No second hand....I disconected spark caps 1 by 1 yesterday, all exactly the same...BUT spark 3 is clear compared with all the rest that are pitch black. Something going in in that 3...the 2 is OK.

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Could this be something daft like a vac. hose disconnected on #3 for a fuel tap vac. connection missing or a vac. check port uncovered. It sounds like #3 is running right (or rather more normally, as one would expect if this is the 'reference carb') and the others are too rich, possibly why it all goes 'pete tong' as it warms up?

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11 hours ago, RickLee said:

 I notice also that this seat has a screen filter apparently taped onto the underside as opposed to the plastic filter in the originals seat.   

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I don't like the idea of a screen on the fuel inlets - far too easy to cause a blockage IMO Never seen a screen on any carbs i've had apart - i'd rather see some crap in the bottom of the float bowl than blocking the fuel inlet - just my personal opinion though! A decent external fuel filter before the carbs is far more useful and user friendly!

Edited by Gixer1460
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8 minutes ago, Gixer1460 said:

Could this be something daft like a vac. hose disconnected on #3 for a fuel tap vac. connection missing or a vac. check port uncovered. It sounds like #3 is running right (or rather more normally, as one would expect if this is the 'reference carb') and the others are too rich, possibly why it all goes 'pete tong' as it warms up?

Dammit I'm thinking the same as you, but vacuum port (for petcock) from number 2 is blocked and fuel line goes to refference cylinder number 3...All 4 vacuum sync ports are closed with thei screws and copper rings...But yes, it looks like something so stupid that when I find out I'll get drunk & commit suicide.

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3 hours ago, Gixer1460 said:

I don't like the idea of a screen on the fuel inlets - far too easy to cause a blockage IMO Never seen a screen on any carbs i've had apart - i'd rather see some crap in the bottom of the float bowl than blocking the fuel inlet - just my personal opinion though! A decent external fuel filter before the carbs is far more useful and user friendly!

Yes, I don’t like the screens,   I’m in agreement. Here is the old seat. It had a screen on it too. Looks pretty old and it seems like not only would it clog, but also impede the flow of fuel as well.  I’m not trying to hijack satans thread,  I’m thinking maybe I can help us both by going over these things. This is my first 4 carb rebuild and it’s pretty difficult. I’m going to ditch the screens and I always run an inline filter. But if this rebuild does not work I’ll buy the new mikunis for 700 bucks. I’m not doing this twice.   Hey Satan, try blowing through the hoses with the carbs off and see if you get resistance in one of them. Gas tastes nasty but I did it and have found one blocked. 

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Edited by RickLee
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3 hours ago, SATANSAM said:

Dammit I'm thinking the same as you, but vacuum port (for petcock) from number 2 is blocked and fuel line goes to refference cylinder number 3...All 4 vacuum sync ports are closed with thei screws and copper rings...But yes, it looks like something so stupid that when I find out I'll get drunk & commit suicide.

Have you tried swapping the fuel tap from 3 to 2?  Curious if the problem switches 

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I poured some carb cleaner into the inlet hose that had blockage (0n water bottle in pic). Let it sit for 20 minutes and blew through the hose . Suddenly it blew gunk through the holes where the two screwdrivers are. It’s unblocked now ...I will proceed to spray clean and rebuild 

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All I can add is that I bought a cheapo Chinese 6L U/Sonic cleaning bath six years ago , and having done a lot of old old carbs, I swear by it .

Best £100 spent that year  . Was a believer in comp air and aerosol cleaners for a long time,  but now a convert to the school of "20 minutes in the bath , wash and then  off you shoot" . Technically you should be able to get the same result with either method , but for me the U/S bath is garanteed to work , and if not sure , another 20 minutes will deffo cure it . 

It's an arse on a bank of four having to split them down, but the hope is, you only do it the once . Without wishing to sound like a smug knob, this is what I did my 750ES resto , and it fired straight up, settled to idle with no dramas. Bike had been sat for 6 years before I bought it , and two years after that , so plenty of time to gunge up .

 

If you can run to it , well worth the investment IMHO . 

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8 minutes ago, PanzerWomble said:

All I can add is that I bought a cheapo Chinese 6L U/Sonic cleaning bath six years ago , and having done a lot of old old carbs, I swear by it .

Best £100 spent that year  . Was a believer in comp air and aerosol cleaners for a long time,  but now a convert to the school of "20 minutes in the bath , wash and then  off you shoot" . Technically you should be able to get the same result with either method , but for me the U/S bath is garanteed to work , and if not sure , another 20 minutes will deffo cure it . 

It's an arse on a bank of four having to split them down, but the hope is, you only do it the once . Without wishing to sound like a smug knob, this is what I did my 750ES resto , and it fired straight up, settled to idle with no dramas. Bike had been sat for 6 years before I bought it , and two years after that , so plenty of time to gunge up .

 

If you can run to it , well worth the investment IMHO . 

I bought one too, but doesn't seem 3 B my problem... I THIN I'M THE PROBLEM. 

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2 hours ago, PanzerWomble said:

Huh 

 

I might have missed it but when your balancing the carbs and you rev the bike the movement of the guages doesn't tell you anything either ? 

Well basically what happens is that the bike, to have all 4 carbs synced, has to be around 2000rpm or more, When throttle blimped 4 gauges act the same...4 carbs with new seals (even throttle shaft seals) butterflies spot on, new needle valve, needle and Oring, spot on float height, 4 carbs in UC, carb cleaner and compressed air...Intake boots to cyl head correct (no response with break cleaner, carb cleaner, contact cleaner or propane) but air box boots are a bit crappy, and can't find any (no stock and hardly any 2nd hand). I personally don't think airbox boots could cause such shit, I've balanced carbs without airbox with no hanging issues, actually the opposite. Thanx, I'm going to get drunk and buy a tractor. 

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2 hours ago, SATANSAM said:

Well basically what happens is that the bike, to have all 4 carbs synced, has to be around 2000rpm or more, When throttle blimped 4 gauges act the same...4 carbs with new seals (even throttle shaft seals) butterflies spot on, new needle valve, needle and Oring, spot on float height, 4 carbs in UC, carb cleaner and compressed air...Intake boots to cyl head correct (no response with break cleaner, carb cleaner, contact cleaner or propane) but air box boots are a bit crappy, and can't find any (no stock and hardly any 2nd hand). I personally don't think airbox boots could cause such shit, I've balanced carbs without airbox with no hanging issues, actually the opposite. Thanx, I'm going to get drunk and buy a tractor. 

To state the obvious it's running rich . 

Assuming  throttle cable and choke cable have slack at idle , and the needels sit down properly ,  I'd concentrate of the pilots screws and jets. Take a look at the attached maybe 

 

Link to basic fault find procedure

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I hate to keep stating obvious things but when I removed the diaphragm caps the screws were mighty frozen, I had to hammer on them a bit with impact screwdriver and other various instruments of torture.  Well just imagine my surprise when I realized that one of the caps suffered a hairline crack after a half hour of abuse in its proximity.   Are your caps solid?  Might be worth looking into.  I’m looking for a new shiny set at the moment.

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Well, I've given the bitch a ride today after 7 bloody months....Managed to lower her down with lean mix on mix screws (1,5 turns out). I pur some tape on 2 air box manifolds to carbs where were some small cracks (on the end of the manifolds stuck to the carbs)....Anyway, riding the bike the idle was very unestable of course...Ir went up or down slowly and died if I didn't blimp the throttle. Like very "organic", like an air leak, but must be on those airbox manifolds. I finaly found 4 in good condition, fckin 70 bux but had to gettem.Receivin them in a 2 weeks. Motor runs well, power in lows mids and highs,just needs the blimming problem solved and tune up...Riding the bike I feel the problem is not so damn catastrophic. Anyway, beer time. By the way RickLee, the caps are spotless but thanx anyway m8!

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