GSX750ES REVS SUPER HIGH AVTER INSTALLING CARBS

[SATANSAM]

Well no luck, valve clearance was correct, bike still revs when trying to balance the carbs...So I'm going to try the other carbs again blablabla...

A part from this, compression is around 90psi or less on 3 cylinders (limit is 99,5psi) and 120psi in the other one..So time to do something about that I supose...

Any suggestions of where to buy rings and stuff? Thanx again

[TonyGee]

how many miles are on the engine ? if you end up taking the top end off do a leak test on the valves with the head upside down. 

[SATANSAM]

3 minutes ago, TonyGee said:

how many miles are on the engine ? if you end up taking the top end off do a leak test on the valves with the head upside down. 

Around 36000 miles...Yep I'll do that...I did it with my little Gurls blouse twin a few years ago and changed piston rings, stems, "brushed" the cylinders with that thing you put in a electric screwdriver, grinded valves seats...But this thing is BIG compared with that twin....A bit scary!  I think it's worth doing, such a nice and motor, and the sound of it!

[TonyGee]

44 minutes ago, SATANSAM said:

Around 36000 miles...Yep I'll do that...I did it with my little Gurls blouse twin a few years ago and changed piston rings, stems, "brushed" the cylinders with that thing you put in a electric screwdriver, grinded valves seats...But this thing is BIG compared with that twin....A bit scary!  I think it's worth doing, such a nice and motor, and the sound of it!

if thats the genuine mileage then it shouldn't need new rings !!!!!!  that tool is a honing tool   putting a drop of oil down the bores will tell you if the rings are worn as the compression will come up.  but sort out the leak on the other set of carbs first before you start stripping the engine down. i still think its carb related.  

 

[SATANSAM]

4 minutes ago, TonyGee said:

if thats the genuine mileage then it shouldn't need new rings !!!!!!  that tool is a honing tool   putting a drop of oil down the bores will tell you if the rings are worn as the compression will come up.  but sort out the leak on the other set of carbs first before you start stripping the engine down. i still think its carb related.  

 

That's it! Honing tool. Man, thanx Tony...AGAIN! 

[Gixer1460]

I'm going to contradict above (pedant sorry!) A honing tool removes metal to size a bore correctly after boring and as a consequence leaves the crosshatch 'scratches' in the cylinder. Use of a hone on a ready sized or slightly worn cylinder just increases piston to bore dimension. For a refurb such as required here you use a 'Glaze Buster' that lightly scuffs the bore surface and take the worn smooth faces off but doesn't change the physical size. I guess a 'dull' hone tool could be used but could make the job worse - pays yer money, takes yer choice! First image is Hone, 2nd is Glaze Buster.

Edited December 16, 2020 by Gixer1460

[dago]

You need to redo the compression test with a warm engine and the throttle wide open or you'll get a false reading, valves clearance won't affect tickover revs but might affect comp test, it in the carbs some where , slide wear, or emulsion tube, or needle wear ? Good luck

Edited December 16, 2020 by dago

[TonyGee]

i never said anything about honing the bores i just told him the name of the tool as he couldn't remember, and if the mileage is genuine then as i said it shouldn't need any work doing.  yeah ideally the compression test should be done with a warm engine. i still think its a carb problem.  

[Gixer1460]

8 hours ago, TonyGee said:

i never said anything about honing the bores i just told him the name of the tool as he couldn't remember, and if the mileage is genuine then as i said it shouldn't need any work doing. 

I know you didn't! - its the tool that is the problem for what is required. Use by an inexperienced hand could make things worse, and a new set of rings won't cure that! And i've had to re-ring an engine at 35k miles - it had been baby'd all its life before me, smoked on start up but ran ok - it just pissed me off. Bores totally glazed over, glaze busted and new rings = good as gold for another 40k till I sold it.

[TonyGee]

16 minutes ago, Gixer1460 said:

I know you didn't! - its the tool that is the problem for what is required. Use by an inexperienced hand could make things worse, and a new set of rings won't cure that! And i've had to re-ring an engine at 35k miles - it had been baby'd all its life before me, smoked on start up but ran ok - it just pissed me off. Bores totally glazed over, glaze busted and new rings = good as gold for another 40k till I sold it.

it just goes to show the people who really over nurse a new engine do more bad than good.  i bought a new xs 250 back in 1980 and took it easy for the first few miles till i had a run in with a mod on his scooter, ended up chasing him around town and riding it like i stole it, it had 60 miles on the clock. after that i didn't give a shit but the engine was strong (for a 250) and faster than any other similar bikes.   

[SATANSAM]

Thanx say what now!?, Dago and Tony...I've got a lot to learn! But getting there....Installing 2nd set of carbs with leveled floats and all clean...If it leaks (like it did before) it must be from the fuel pipes  between carbs (faulty O rings)...I THINK! haha BEER TIME fckit.

[TonyGee]

if you put the carbs in a vice to hold them and fix up a fuel supply you will have a better idea where the fuel is leaking from. a common problem is the float valves not sealing properly. 

[SATANSAM]

21 hours ago, TonyGee said:

if you put the carbs in a vice to hold them and fix up a fuel supply you will have a better idea where the fuel is leaking from. a common problem is the float valves not sealing properly. 

Bad luck....Assembled the carbs, floats according to manual specs (22,4mm +- ), put them on the vice and they leak from the 2 outter fuel pipes connecting the carbs, dried out O rings I supose...They're not too expensive....Noy I've got to see if it's not crazy to separate the carbs to fit these pipes in!

[TonyGee]

at least you've found the problem. 

[SATANSAM]

2 minutes ago, TonyGee said:

at least you've found the problem. 

Yep! But it's not that easy to find them...Whould you change them from one set of carbs to the other one? I supose it's not a good idea but...

[TonyGee]

2 minutes ago, SATANSAM said:

Yep! But it's not that easy to find them...Whould you change them from one set of carbs to the other one? I supose it's not a good idea but...

no, best to buy new to be on the safe side. 

[SATANSAM]

No luck with the pipes...The ones that leak are out of stock...I'm going to gettem out and look for Orings somewhere to see if they fir...Dammit what a lesson

[Captain Chaos]

After my carbs spent 8 months on a shelf i installed them, filled them with fuel and they started leaking. 
Next day i wanted to fix them but they didn't leak anymore. Apparently the dried out rubbers fixed themselves after being in contact with fuel. 
This was several years ago, been fine since. 

[TonyGee]

1 hour ago, SATANSAM said:

No luck with the pipes...The ones that leak are out of stock...I'm going to gettem out and look for Orings somewhere to see if they fir...Dammit what a lesson

make sure they are petrol/ethanol proof 

[SATANSAM]

2 hours ago, Captain Chaos said:

After my carbs spent 8 months on a shelf i installed them, filled them with fuel and they started leaking. 
Next day i wanted to fix them but they didn't leak anymore. Apparently the dried out rubbers fixed themselves after being in contact with fuel. 
This was several years ago, been fine since. 

I tried about 3 times and I think they don't even exist anymore in mine! We'll see...But we're getting there! Thanx

[SATANSAM]

1 hour ago, TonyGee said:

make sure they are petrol/ethanol proof 

Will do! Cheers m8

[SATANSAM]

Man, those bolts are impossible to unscrew....WD40, heat and ice.....Crazy....Gonna leave them all night with wd40 but they are VERY TIGHT. Each step is a fail fkit

[Pudzrx]

Give them all a sharp tap with a hammer first and make sure you use a proper jis screwdriver. 

Puddy 

[SATANSAM]

9 hours ago, Pudzrx said:

Give them all a sharp tap with a hammer first and make sure you use a proper jis screwdriver. 

Puddy 

Thanx Puddy!

[Gixer1460]

Never had one resist the charms of an Impact Driver!