Carb questions for the oiler

[88gsxr750]

Carb questions...

So my 88 750 was running like ass. I had a hard time getting rolling from a stop light with out clutching the crap out of it. rolling it ran fine. around 10k rpm under hard acceleration it would suddenly cut out. <- I thought that could possibly be the old kick stand switch. All these issues developed after using sea foam in the gas...

I finally got around to pulling the carbs. I took them apart cleaned everything and resembled them. I did not sync them. I got the carbs back on the bike. It ran great at idle. when it came to the road test not so much... still ran rough at low rpm. like starved for fuel. same issue didn’t like taking off from stop lights. also at 4-5k and 9k rpm there were dead spot. also lots of popping on deceleration . which from what Ive read is a lean issue.

I ran a tank of gas threw it. the bike now runs much better. the dead spot at 9k rpm is gone. throttle is much more responsive and pulls okay.

I am getting horrible fuel economy now. When I last had the carbs serviced about 5000 miles ago. I was getting 150 miles a tank. I slowly lost fuel economy. I was getting 130 miles a tank then did the sea foam treatment to try and help bring it back to life.

well I just got done running a tank a gas threw the bike and I got 100 miles to the tank.
I'm def. no carb guru so basically I'm looking for some advice as to what to do to get it running better.... It definitely seems like its running lean....

[88gsxr750]

I was reviewing the sticky. when i resembled the carbs I did not set "float hight" I just popped and pressed in the plastic bits... this may be causing the lean issue.

what is a good float hight?????

[rodriguez]

14.7mm I believe, but check the service manual sticky.

I would get new plugs, valve job, then remove the carbs and go throu them.

In my experience is best to take your time with the carbs and do everything in one shot. Write down your carbs settings in a piece of paper , then clean them. New pilot screw o-rings,actually it would be best to replace all of the o-rings in the carbs, set float height,synch.

Also very inportant that the fuel tank is clean of rust. If not you'll be cleaning the carbs every month.

[88gsxr750]

kool thanks for the advice

....any recomendation as to where to pick up a gasket set?

[javadog]

Originally Posted by 88gsxr750

It definitely seems like its running lean....

Not if you are using more fuel...

JR

[slingshot1988]

Just had the exact same issue with my 88 750. I did a total overhaul of the carbs and a sync. The biggest issue i found was that my needle jets ( emultion tubes) had worn to an oval and the needles themselves were worn. Replaced the needles and tubes and now its good to go all the way through the RPM range with no dead spots and no isses at low RPM.
Just my 2 cents.
Cheers

[88gsxr750]

I appreciate your input. there is no doubt in my mind that everything about the carbs could be replaced. at this point im willing to do that. I have no idea what "kit" to get or the size jets and what not i currently have. I'm willing to replace everything inside all 4 carbs. just don’t know where to start... I've replaced so much on the bike only thing left thats not original to me is the bottom end.... getting sick of working or paying to have it worked on instead of riding. like I said I'm no carb guru so i can use any advice ideas or places to buy parts that anyone wants to recommend

[slingshot1988]

I def hear you on the frustration.........
I put in a dynojet stage one kit, came with jets and needles. I had to buy the emultion tubes from my local dealer. put in all new O rings and set the floats.
I am running a K&N in the stock air box with a V&H SS2R full system and the stage one kit works great.
On the cleaning side, I tried the Pinsol trick and wow they came out like new!!!!
You can get all of the parts and an O ring kit on ebay for the most part, and shouldnt cost more than 150 bucks or so.

Hope it helps.

[rodriguez]

If you are getting a jet kit you can get it from this member.

http://www.gixxer.com/forums/showthr...hlight=jet+kit

The emulsion tubes and o-rings you can just buy them from here.

http://www.ronayers.com/

Or maybe here.

cheapcycleparts.com

[88gsxr750]

thanks for the links man. I'm going to get some parts on order and then study the carb sticky lol. Thanks to every one who replied

One last question though.... would it be worth it to replace the diaphragm/slide? or the plastic housing the emulsion tube sits in. Or how about the floats?


.....maybe I should just looks for a nice set of used carbs

[rodriguez]

No need to change the diaphragm unless its damaged.

No need to change the slide either. If it is damaged i think there is a company in the UK that make them. Search the thread about o-rings , i think its there.

Also there is another o-ring on the bottom of the emulsion tube housing.

If you buy a set of used carbs you'll still need to replace parts. There is no way around it.

[Oddsen]

I`ve got the same frustration asy ou a time ago
My problem was the carb who is pulling the rest up when throttle on ( middle )
The carb was wear at the axle input and by that not possible to sync
My bike has 80 000 km on the clock so there might be problems around that mileage.
Changed the carbs with a dynojet stage 1 and V & H open can with uni air in the oem box
Works nice now. But it can always get better.

[carter turk]

My gas mileage improved 16 mpg when I dipped carbs in water and vinegar and changed all the orings. Changed the emulsion tubes too.

Used the Factory nickel plated ones. I got the O-rings from O-rings Inc.

The O-rings listed below fit on 36mm carbs from a '90 GSXR-11

This thread in the search function helped me to find all the O-rings.

Re: BST36ss Carb o-ring sizes.

3mm x 1mm bn70 for mixture screws

3.5mm x 1.5mm bn70 for top cap

5mm x 1.5mm bn70 for small float post

7.5mm x 1.5mm bn70 for large float post

8mm x 1.5mm bn70 for can't remember (maybe the T fitting between carbs?)

10mm x 1.5mm v75 for bottom of slide guide