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Discussion Starter #21
Sorry, found it in the manual. It connects to a small nipple on the back side of the petcock which I never noticed before. I hooked it up but didn't expect any change which I confirmed. I think I'm going to break the rack of carbs down and go through them all. When I put them back together, I will swap #3 with another and see what comes of it. Thanks
 

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Discussion Starter #23 (Edited)
It was not hooked up, but since I kept removing/replacing the carbs, I was just using PRI on the petcock to fill them and quickly run the bike.

You're question made me think of something. I just went out to the garage and switched the petcock selector to ON. The bike started right up on choke and ran for a few minutes, but then started running rough and stalled. It would start up again, but rolling the throttle on would stall it. So, it looks like there is not enough vacuum being pulled on #3? Would this change the diagnosis of carb at all?
 

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Interesting. It would have been interesting also to see if you moved the petcock tube to one of the other carbs if you had the same result. That would definitely have pointed to a carb/vacuum issue. While the carbs are off maybe a check on the valves to verify clearances/health there as well.

Check the carb sticky in this forum for a good source for all the seals/bushings/o-rings for the carbs.
 

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Discussion Starter #26
On my bike, only #3 carb intake holder has a nipple, so not sure I could have done that extra test.

While I wait for the carb parts to arrive, I might as well check the valve clearances. Thanks, that's a good suggestion.
 

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Split the rack and broke all the carbs down. Next step - order rebuild kits and bath in the sonic cleaner.
That picture brings back memories... I only have one carbed bike ATM, which hasn't run in at least two years; but I'm extra careful to drain everything when I park it to avoid that. I know where you're coming from, its very time consuming and frustrating to go through all of that just to reinstall them and have the same issue.
 

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Discussion Starter #28
I measured tappet clearance. They were all over the place. Looks like I have to pull the cams which I never like doing. Shim under bucket style sucks.
 

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Discussion Starter #29
I should have all the shims today and will install the cams and re-check tappet clearance. The carbs are clean and I'm waiting for gaskets and o-rings from Thailand. Hopefully they'll land here next week.
 

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Discussion Starter #30
I finally received the carb kits and they are excellent. I put in all the new o-rings and gaskets and re-assembled the rack. I also installed new shims and checked tappet clearance. All clearances are in spec. Cold compression tests are 155-160 across the cylinders. I put the rack back on and ran the bike appears be running only on cylinders 3 & 4 based on the fact that head pipe temps on cylinders 1&2 is about 200 degrees. So frustrating.

Couple questions:

1.) I tried capping off the fuel hose on 3&4 side and no change. What is the purpose of two hoses feeding the fuel rail?

2.) I checked for spark and assumed the coils were working since 3 & 4 are on separate coils. Any suggestions for next steps? I'm completely stumped.

Thanks
Nick
 

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There should be a smaller vacuum line connected between #3 and the petcock. This allows fuel to flow as long as there is vacuum present.
There should be two lines coming off the petcock, one feeds #1 and #2 carbs, the other feeds the #3 and #4 carbs.
Each has a small 'T' fitting between the carbs.
Have you verified there is fuel in the line for #1 and #2?
If you disconnect both lines from the tank, you can apply a small vacuum to the #3 line and see if fuel comes out of both sides of the petcock. (something like a brake bleeder tool works)
If you open the drain screws on #1 and #2, you should hopefully have fuel in the bowls.
Did you carefully set the float heights on all four when you did the rebuild?
Setting the pilot screws to 2.5 turns out is a good start, but will likely need adjusted. Mine ran best with them around 3.5 out after tuning.
 

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Discussion Starter #32 (Edited)
Thanks for the reply. Interesting. My petcock only has 1 nipple for fuel with a T in-line that splits into a fuel line that runs to 1&2 and 3&4. I have the vacuum line from #3 carb insulator to the carb, but was using prime to fill the carbs. Looks like someone swapped either the tank or the petcock. I set float heights at 15 mm. Maybe the petcock was unable to supply the carbs enough fuel. I'll order a new petcock.

568797
 

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I don't see why that wouldn't work, as long as you get fuel out when vacuum is applied.
I believe the California model has a single feed with an inline 'T' fitting.
Manual says float height should be 14.7, though 15 should be close enough.
Next would be to verify fuel has made it to the bowls.
If the float needles are installed wrong, they could be sticking and not allowing fuel to flow.
Did the kit come with new needles?
 

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And should check the butterflies also. When you re-assembled the bank, did you get the synchro springs back in the right places?
 

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Discussion Starter #35
The kits I bought didn't have float needles since they looked OK to me. I checked the #1 bowl and it had fuel in it, so they are getting fuel. Based on your comment about the California model having a single feed, I'll see if I can use the petcock and not spend the $ on a new one.

I'm glad you mentioned the springs because I don't think I have the right ones - they look too thin.
 

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Discussion Starter #37
Did some more testing. Put new plugs in cylinders 1 & 2 and ran it for a few minutes. plugs were not fouled and didn't appear to be wet. I checked for spark on both and it's there when I crank the starter, but it seems weak to me though I'm not sure what strong would look like to be quite honest.

I checked for gas in the float bowls and fuel drained out of 1 & 2 when I opened the drain screws. I'm going to wait until I get the springs I ordered for the carb syncs and try that. If that doesn't fix it, I may have to wave the white flag and bring it to an Indy shop for someone to look at it (which would be a first for me.).
 

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If you pull the carb bank again you can reverse the order and put 1/2 in 3/4 and vice versa. Then see if the problem follows. If you have spark on 3 and 4 you have spark on 1/2 as its a wasted spark system and both plugs (1/4, 2/3) fire at the same time. Sounds like a carb issue with 1/2, you appear to be getting fuel in the bowl, but not pulling it out. Check the idle circuits, check for tears in your CV diaphragms, and check your jet needle valve for blockage.
 
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