1978 GS550 issues

[Jesse002100]

I greatly appreciate any help that you can give. I have had the carbs cleaned and rebuilt, changed the points and replaced the coil packs from the tips from users in my last posts. i set the points and timed it to the manual's info, its running a little bit better but still bogs down in the higher rpms between 4000 and 5000 it seems like it will stall if i stay on the throttle, it tops out around 50 mph in 6th gear and im out of ideas on what can be wrong now.
any thoughts would be greatly appreciated
Thanks, Jesse

[BassCliff]

Greetings and Salutations!!

Hi Mr. Jesse002100,

"Having" the carbs rebuilt is seldom beneficial. Many members here have had to rebuild their carbs two or three times before they were clean enough. If you are at all able, do them yourself. Then you will know they are done correctly. The proper procedure is referenced below.

Here's my unofficial "mega-welcome". Pay particular attention to the "Top 10 Common Issues", the Carb Rebuild Series, and the Stator Papers. Now let me roll out the welcome mat for you...

Please click here for your mega-welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

[satchmo]

What's the condition of the carb boots where they attach to the engine?

Leaks in the o-rings inside the boots are common on the older bikes and can make them run poorly.

[Nessism]

Did you replace the airbox with pod filters or is everything stock?

[Jesse002100]

as for the air filters i put 4 k&N filters on it because the air cleaner and air box on it were empty and i thought it would help a bit on the power side
it seems there is a very small crack on the carb boot for cylinder 4 but i have been looking for new ones and cannot find them

[BassCliff]

Hi,

If you've put pod filters on your carbs you will also need to install larger jets or you will be running lean. Having cracks in your intake boots means that even more air is getting in the mixture making it even more lean.

What do you mean the airbox and air filter were "empty"?

I just bought intake boots from http://www.flatoutmotorcycles.com . As long as you're shopping, visit http://cycleorings.com and get a set of intake boot O-rings and carb O-rings (for when you rebuild them).


Thank you for your indulgence,

BassCliff

[Jesse002100]

good but now not running 78 gs550

http://cycleorings.com/intake.html
77-79 550's use 28mm O-rings (which I don't carry) and 16mm screws.
i thank for all the help so far im going to get some o-rings from a dealer i hope. i took off the k&n's put on the stock air box i got on craigslist the filter in the airbox has no filter on it just the main metal on the inside so i will look for one of those. after putting on the stock airbox it ran great for about 80 miles of the 100 mile run i went on then it seemed like it was only hitting on 2 cylinder, then my brother thought the points needed adjusted again and after he tinkered with it, now it doesnt start at all. so if anyone has any ideas i would greatly appreciate it
Thanks Jesse

[Nessism]

I have some of the O-rings if your dealer doesn't. Send me a PM if interested. For the filter, just get a piece of flat filter foam - get the fine mesh foam, and install that over the metal cage in the airbod. Most motorcycle shops stock it.