Inazuma 750 carburetor nightmare

[terecha]

Hi

 

I don't know what to say.

 

I had Suzuki Inazuma 400 and 2 sets of carburetors died because of needle valve leakage (maybe needle valve seat as well). Changed the valves and problem was still present. Seats are not replaceable. Bike couldn't start due the fuel flooding.

 

Later I purchased Inazuma 750. First set of carbs died due the age and bought second set of carbs, which looked like brand new. Taged only 15 000 miles. But they have horrible leak . Changed the needle valves and still leaking. And like in 400's model case, bike can't start due the fuel flooding.

All the other parts are in the perfect condition. Compression of engine is amazing, good coils, good sensors, new spark plugs, filters etc.

 

PS. I can still organize the setup with 400 or 750 engine. Have all needed parts.

 

Maybe do you have any tips? Or should I scrap this bike?

 

Many thanks!

Edited June 19, 2022 by terecha

[TonyGee]

they use the same carbs as the bandit 600 if that helps ? 

[terecha]

26 minutes ago, TonyGee said:

they use the same carbs as the bandit 600 if that helps ? 

Sadly. Not.

[TonyGee]

33 minutes ago, terecha said:

Sadly. Not.

did you use genuine float valves ?  

[terecha]

5 minutes ago, TonyGee said:

did you use genuine float valves ?  

Used the tourmax replacement first, no success. Later purchased the genuine, but their rubber tips were very hard, so returned them to the dealer

Edited June 19, 2022 by terecha

[TonyGee]

1 minute ago, terecha said:

r rubber tips were very hard

but did they stop the leak ?  

[terecha]

1 minute ago, TonyGee said:

but did they stop the leak ?  

No

[TonyGee]

4 minutes ago, terecha said:

No

ive fitted quite a few genuine float valves and never seen one fail,  where exactly is the leak coming from ? 

[terecha]

1 minute ago, TonyGee said:

ive fitted quite a few genuine float valves and never seen one fail,  where exactly is the leak coming from ? 

From overflow tubes and fuel is present in the airbox and cylinders (too much) as well.

[TonyGee]

I assume the float heights where set right !!!!   

[terecha]

2 minutes ago, TonyGee said:

I assume the float heights where set right !!!!   

I checked this and are perfectly set.

[wraith]

 have you replaced the rubber o ring around the needle valve seat/holder?

[terecha]

6 minutes ago, wraith said:

 have you replaced the rubber o ring around the needle valve seat/holder?

Valve seat is pressed permanently into the carb body (can not be removed without damage). There is no oring around and no oring inside the seat.

[terecha]

https://www.bike-parts-suz.com/suzuki-motorcycle/750-MOTO/GSX/2000/GSX750Y-E4-/ENGINE-TRANSMISSION/CARBURETOR/18/3061688/M/1562

[TonyGee]

you find the O ring on the 1200 bandit carbs. 

[wraith]

Ok, they are a 32mm carb if I'm right?

If so, get a set of MK1 bandit 600 carbs, swap the pilot jets over and run it on them, or even get a set of gsxr/b12/gsx750f carbs and inlet rubbers and put them on. The gsx750f would probably be better  and you'd get some more power out of the 750 engine.

 

[TonyGee]

1 minute ago, wraith said:

they are a 32mm carb if I'm right?

yeah they are    the 750 and 1200 inazuma's use the same 32mm carbs. 

[terecha]

3 minutes ago, wraith said:

Ok, they are a 32mm carb if I'm right?

If so, get a set of MK1 bandit 600 carbs, swap the pilot jets over and run it on them, or even get a set of gsxr/b12/gsx750f carbs and inlet rubbers and put them on. The gsx750f would probably be better  and you'd get some more power out of the 750 engine.

 

I tried the gsx750f carbs, bike runned but I couldn't adjust it.

When accelerated engine had serious breaks in revving.

Not an expert and didn't know how to fix it.

Edited June 19, 2022 by terecha

[TonyGee]

this is why i said about B6 carbs,   

i put a set of b6 carbs on a b12 engine without changing anything, they worked spot on. even though the jetting is slightly different on the 1200 inazuma. 

[terecha]

What other carbs would fit? Mikuni RS34? Keihin FCR?

[terecha]

14 minutes ago, TonyGee said:

this is why i said about B6 carbs,   

i put a set of b6 carbs on a b12 engine without changing anything, they worked spot on. even though the jetting is slightly different on the 1200 inazuma. 

I am not sure if they can fit, because in bandit airbox is completely different.

[TonyGee]

21 minutes ago, terecha said:

I am not sure if they can fit, because in bandit airbox is completely different.

not sure what your setup is ?  are you using an inazuma frame and engine ? 

[wraith]

28 minutes ago, terecha said:

What other carbs would fit? Mikuni RS34? Keihin FCR?

If you don't know about setting up carbs (ie the gsx750f carbs you tryed) the above carbs will be way out of your knowledge to set up and they don't go with the standard air box. So you would need to spend time getting them set up on a Dyna rolling road.

[terecha]

18 minutes ago, TonyGee said:

not sure what your setup is ?  are you using an inazuma frame and engine ? 

Yes. Stock frame and engine

[terecha]

13 minutes ago, wraith said:

If you don't know about setting up carbs (ie the gsx750f carbs you tryed) the above carbs will be way out of your knowledge to set up and they don't go with the standard air box. So you would need to spend time getting them set up on a Dyna rolling road.

This is what I supposed