Reviving the 88. Throttle response issues.

[AJBinVA]

So to start this bike has been sitting for awhile. The tank was full of rust and sediment.

I removed the tank and got every last bit out using a combination of muriatic acid and electrolysis. Looks brand new now. I replaced the fuel lines and drain the fuel bowls and flushed with seafoam.

Bike fired right up on carb cleaner and would idle on its own albeit at 4k rpm and I couldn't get it to run without a good amount of choke (air box on). Lots of popping and sputtering from exhaust and a mist or 2 out carb #2 and #4. Let it run for about 20 minutes to pull some good gas through and sprayed seafoam.

Next day did the shotgun. Diaphragm and slides looked great. Needles looked awesome for #1, #2, and #4. The needle for #3 won't come out. Must be a blockage as I can't get enough air pressure to it to push out. While draining the bowls I got a tiny bit of particulate almost colloidal in size.

Here is how it runs now. Will idle without choke at 1200rpm but revs and hangs around 4000 rpm for a few seconds before coming down. Sorry for the sideways video. What should I do next. Any suggestions for getting the mixture screw out of #3?

https://youtu.be/fpcCExAICZE

 

[93max]

The needle or mixture screw won't come out?
I did expect it to hit my finger pretty good to but that wasn't the case as the air can go out the other jet too.

 

[93max]

Ignore my post. I just saw mixture screw! DUH!

 

[93max]

I think I held my finger over jet 2 to increase pressure on the screw.

 

[AJBinVA]

Yeah I put a rubber plug in #2 and still couldn't get it out.

 

[93max]

Does it move at all? Shoot some PB Blaster down 1 and in the hole for it. Maybe jet 2 also,

 

[AJBinVA]

It's loose. Definitely unthreaded. Hooked the vacuum pump up to the hole and barely sucked some cleaner through. Circuit is definitely clogged. Threads in and out fine.

 

[AJBinVA]

Just got it. Voila moment. Found a piece of marine heat shrink tubing the perfect size. Pushed in and twisted and came out. Needle looks good. Need to clear out the clog somehow.

 

[AJBinVA]

And get the o ring and washer out.

 

[AJBinVA]

Thinking the revving is a lean condition. Boots seem to be in decent shape but I am getting the feeling I'd be better off taking the carbs off and going through the float bowls too.

 

[dannymax]

And get the o ring and washer out.

Looks like the o-ring & washer are already on the mixture screw....just in the wrong place. Washer goes in front of the spring (in the photo it's behind it) and the o-ring in front of the washer.

 

[AJBinVA]

Got everything back together. Runs about the same. Lots of popping and sputtering from the exhaust when giving it a blip off idle. Checked the boots for cracks and sprayed around them with carb cleaner, none seem to be leaking. Ordered a Carbtune Pro 4.

Am I being too impatient and maybe it just needs some time to loosen everything up from sitting?

 

[Fire-medic]

If you haven't completely disassembled the carbs and soaked them, and then reassembled them correctly, w/all passages unplugged, I suspect it's gonna continue to work like this.

 

[AJBinVA]

Carbtune came in the mail the other day. First try at syncing the carbs didn't go well. Wouldn't stay at idle. Had lots of sputtering. Called it quits and decided to do a compression rest due to some blue smoke.

Compression was great all 4 cylinders between 180-190. Plugs looked bad in 2 cylinders. Ok in the other two. Couldn't get good pictures. Put new plugs in. Started it up and the bike idle better.

Hooked the carb sync up and got them all dialed in. Bike is running much better. Need to get the air/fuel dialed in but going to take the rack off and clean it all out. Gaskets just came in today.

 

[AJBinVA]

After riding for a few days the bike crapped out a couples times. Took the carbs off and tore into them. Carbs were pretty clean inside and looks like someone started to rebuild them at one point. Coasting enriched diaphragms were practically melted in #1 and #2 thank God they were in good shape in #3 and #4 because they are stupid expensive. Ready for parts to get in to get them back together.