77 GS550, junkyard dog....

[t3rmin]

Make sure you do a vacuum sync on those carbys! Especially if you've been having trouble with some cyls running better than others -- this'll make all the difference in the world.

[Dave8338]

ok soooooooooo, spent my entire saturday trying to get bottom four screws out of the intake boots so that i can replace the o-rings....one is now stripped badly. cannot reach with vise grips like i could the top 4...cant fit drill or impact wrench into space. dont want to pull the engine just to access 4 lame screws....any ideas??

will

Use a block of wood (1"x1"x1') and small hammer. Place the block of wood on the outer most edge of the intake boot where the rubber molds over the casting and tap it lightly in a counter clockwise direction...the whole boot will turn and if needed, repeat the process, rotating the boot clockwise with your hand and then try it again...they will come loose, you'll have to trust me on this one.

[gerwintown]

update

hey guys,

after a day of piddling, unable to get the bike to achieve what it had previously done 5 days prior (ie run), i have been able to get the bike on the road.

i finally disassembled the petcock as it was not functioning properly...it leaked fuel through the outlet when placed in the "on" position despite the absence of vacuum. i found a piece of rubber from god knows where that was blocking the vacuum activated plug from closing all the way. removed that dirt and reassembled and the petcock now functions properly. i was very careful not the damage the diaphragm when i pulled the pieces apart.

i also noticed that i had been running a "vent" tube instead of the "vacuum" tube from the carbs to the petcock. obviously that was causing me some problems. that has been corrected and the petcock and fuel delivery is cool.

first, i want to say, this bike is sweet, i believe ive gotten it to run very well. acceleration is strong and smooth throughout the power band and at low, mid, and full throttle. there may be the slightest hesitation during the transition between low to mid throttle, but i think with a few adjustments i can get that in order.

i still have one problem, and that is that sometimes when i come to a stop while riding, and always when i turn the bike off, the carbs literally dump gasoline from the overflow tubes on the bottom of the float bowls. i would say it dumps enough gas to fill a few float bowls....ive noticed that the #2 carb is most often the culprit, but i have seen all four dump gas aat once. seems like its unloading all the gas inbetween the petcock and the float chamber. now, i believe i have the floats set to 24mm, +/- 1 mm, but of course i could be wrong. my clymers manual says that it should be set to 26. i think i had read 24 somewhere on the site. which is correct? my only other thought is that the float valve itself is getting stuck open. when i last examined the valve that was visible wear (as in not perfect) on the cone, but it seemed so slight, it was more like a slightly darker ring around the cone, you couldnt feel it with you finger or fingernail. with the carbs upside down, tapping on the floats produces a springing action. didnt seem like anything was catching or inhibiting the movement of the float.

anyways, ill check the float heights and see if that fixes it, and then i will consider looking for new float valves. i have the method for measuring and adjusting the float heights from my clymer manual.

any ideas, or advice, is welcome.

otherwise, the bike starts on the first or second kick, everytime, hot or cold, and holds a nice idle when warm of 1200 rpm. and it has consistently for the past 3-4 days.

oh yeah, and the bike is now shifting fine, it loosend right up just like i hoped. however, the shift pedal doesnt return to a neutral position after a shift. lets say i am upshifting, ive just shifted from 2nd to 3rd gear...i must first tap the pedal DOWN to what im gonig to call the neutral position, before i can shift up to 4th gear. repeat to get to 5th...etc. same thing with downshifts, which is really the most annoying part, as i live in the city and mostly will be shifting between 3rd or 4th gear down to 1 frequently. is this how its supposed to be?? or do i have a worn out spring somewhere?

also, this bike is way faster than my old 82 yamaha 400 maxim. cant wait till everything is finished and tight. in two weeks im gonna be breaking out the paint gun and putting my fiberglass fabrication skills to work on this bike. im going to hammer knee indents into the gas tank, fabricate a seat and attatch the seat to the gas tank in a way so as to make the gas tank, side panels,seat and rear cowl one piece. more on that when the time comes, so look for more exciting updates in the weeks to come, with pictures. i need to grab some more "before" pictures first....and dont worry, the PO did some nasty rattle can paint job on the tank and side panels (and petcock.....idiot), so im not destroying anything that would be considered original.

[gerwintown]

pictures!

these are pictures of the bike as it was dropped off by the truck

[gerwintown]

pictures!!

different view

[gerwintown]

yup

another view

[gerwintown]

and another!

and another view....this one i will use to produce a rendering of what i plan on doing with the bike.....see the following post please

[gerwintown]

see here

ok so this is a quick and dirty photoshop rendering of my plans for this bike.

the rear cowl is made from layered and then vacuum bagged veneers, essentially bent plywood that you see on a lot of furniture (eames). with the vacuum bag system, i am able to get even clamping pressure during molding and thus a very nice bent plywood part with compound curves galore. the final or top veneer should be east indian rosewood if i can find enough of it, or well polished maple. im not quite sold on the color yet, im using some left over 2 part urethane from some previous school projects (prototypes of consumer product concepts) and this happened to be one of them.

the colors i have are this sort of navy blue, a bright lime (almost kawasaki) green, a roe (orange-ish pink) and i believe i have a pale blue and the same metallic green paint you see on new vw bugs. i will decide soon....


the overall shape of the piece might change of course due to the demands of the veneers, but this is the idea.

[gerwintown]

also, so i dont know if i said this before, but i got the bike running only to find that when shutting the engine off or sometimes stopping at stoplights i would see (hear and smell) gasoline momentarily purge from the overflow tubes on the carbs.

well i took those apart the other day, found that my float seats and almost completely unscrewed themselves and the floats were of course completely stuck. well i tightened those back up and readjusted the float height....i must have been WAAAAAY off on the float height because i changed it to 26mm as per the clymer manual's instruction and i must have been 10mm off previously. welll, now it seems the changes i made have screwed everything up. it was starting and idling and running just fine, with a few flat spots of course but now it will not idle or rev with the choke off....any ideas as to why this might be??? what do i need to do now?

[Dave8338]

Have you done the o-rings on the intake side of life yet? Also, you mention that the #2 carb seems to be the main issue with respect to the excess fuel...petcock? See if, when you pull the vacuume line for the petcock off the #2 cylinder, you have fuel dripping out of the line, with the petcock in the run position.

[gerwintown]

hey yeah, i did the oring change on the intake boots. i think the reason that the left bank of the carbs was leaking noticeably more was due to the fact that with the bike on its stand it was leaning to the left.

and like i said, the needle seats had almost completly unscrewed themselves, leaving the floats pressed as high (or low with the carbs upside down) as possible, allowing way to much fuel to enter. it would start leaking when the throttle closed and stop shortly after the engine stopped drawing vacuum on the petcock. thats the best way i can describe it.



actually, put in a full tank of gas today and started it up. looks like its running just fine, its at least got a solid idle when fully warmed up and with the choke off. havent taken it for a spin yet but i think it should be ok. my next step is to conduct the highest idle process to make sure the air screws are dialed in.

so, more or less, everything is ok with the carbs now.

thanks!

[Dave8338]

If you have a center stand, use it...seems to keep things running much better. :-D Also, I like the photo shop rendering, but the air filters look a "little thin" to me!!!!! \\/

[gerwintown]

If you have a center stand, use it...seems to keep things running much better. :-D Also, I like the photo shop rendering, but the air filters look a "little thin" to me!!!!! \\/

ha....pretty much.

[onchiman]

Nice job hanging in there with this bike. Lots of folks would just have given up! If you're willing to learn (study these pages) and possess some perseverence, you'll be rewarded in lots of ways. It's good to see young people appreciating these old bikes and all the stuff that goes with them. Tinkering is a way of life.