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View Full Version : 1982 GS550 Intake Problems, or Help Me Decide



siamesegun
05-17-2015, 5:49 PM
Alright, got the solo seat install finished on the Suzie today and she fired but was pissing gas so I decided to strip the carbs and give her a good once over since the wife is gonna ride this one and I don't want her having to restart the thing every stop sign she comes too.

Well, long story short as I was putting the carb rack back into place one of the outlet tubes on the airbox shredded and is fucking doneso... Kaput. So now I'm trying to find a new outlet tube (harder than one would think) or figure out if a different filtration solution is appropriate. I hear tons of shit talk about pods, and think it would be worth it to shell for the K&N set for this bike if it means less trouble especially since I tried some EMGOs a buddy had that were too tall to fit between the carbs and the frame. I can rejet, but don't want to end up with a grenade on wheels if I go pods.

Can I repair the boot with rubber cement and expect it to work?

Are pods really as bad on these type carbs as I've been reading?

Anyone know any decent pods that are shorter than the 2 3/4 (tops) I have between the carbs and the frame?

Anyone got any outlet tubes from their airbox they've been hoarding and willing to part with?

Cheers dudes, thanks in advance.

Dieselchanic
05-17-2015, 8:09 PM
I know that some of the boots can be really difficult to find. I haven't had any experience myself, but I've read of guys repairing intake boots on the vintage L-Jetronic fuel injection system on VW's using something called Shoo Goo or Shoo Goo 2 found in sporting goods stores. It apparently adheres well and stays flexible.

sinsai750
05-17-2015, 9:02 PM
got a pic of what you need I have some parts for a gs550 but mine has the two carb set up instead of 4

Dpratt07
05-18-2015, 5:32 AM
Dude, i have the same year and model. i run four black foam uni filters on mine and that bike is mean. Obviously i rejetted the bike with 115s outter and 117.5s inner and shimmed the needles with a washer. I rode my bike stock in good running order and it was a turd. This bitch will move now.

siamesegun
05-18-2015, 7:04 AM
Dude, i have the same year and model. i run four black foam uni filters on mine and that bike is mean. Obviously i rejetted the bike with 115s outter and 117.5s inner and shimmed the needles with a washer. I rode my bike stock in good running order and it was a turd. This bitch will move now.

I was looking at the foam uni's, they look like a decent option - especially since I'm being budget conscious on this bike because I'm sure the wife is gonna beat it up learning to ride it. I just need it to be reliable enough on start up.

Thanks for the recommendation, I'll probably spring for a few foamies and see what happens. I can't remember clearly (slept since then) but I thought these carbs had 135s in them? Anyway, I'll keep digging. This bike will rip once I get it back together.

siamesegun
05-18-2015, 7:05 AM
got a pic of what you need I have some parts for a gs550 but mine has the two carb set up instead of 4

I'm at work now but I'll hit you up. The outlet tubes are the soft rubber between the plastic expansion chamber that comes from the airbox and the carbs.

siamesegun
05-18-2015, 7:07 AM
I know that some of the boots can be really difficult to find. I haven't had any experience myself, but I've read of guys repairing intake boots on the vintage L-Jetronic fuel injection system on VW's using something called Shoo Goo or Shoo Goo 2 found in sporting goods stores. It apparently adheres well and stays flexible.

I've got some Shoe Goo, that might be a good option. I was thinking rubber cement from bike tube repairs since it stays pretty flexible but I know the solvent in it will warp the rubber permanently so I think it will be a once and done type deal.

Dpratt07
05-18-2015, 7:54 AM
I was looking at the foam uni's, they look like a decent option - especially since I'm being budget conscious on this bike because I'm sure the wife is gonna beat it up learning to ride it. I just need it to be reliable enough on start up.

Thanks for the recommendation, I'll probably spring for a few foamies and see what happens. I can't remember clearly (slept since then) but I thought these carbs had 135s in them? Anyway, I'll keep digging. This bike will rip once I get it back together.

Nah if u have cv carbs Stock is like 92.5 i think.

The filters work very well and are flexible which is nice for the tight area. Heres mine. I liked them cause of the ease of removal when tuning
http://i59.tinypic.com/rj07cn.jpg

siamesegun
05-18-2015, 8:39 AM
Nah if u have cv carbs Stock is like 92.5 i think.

The filters work very well and are flexible which is nice for the tight area. Heres mine. I liked them cause of the ease of removal when tuning

Are the the PK-82 UNIs? Thinking this is the route to take but the measurements seem off. Need 52mm ID on the boot.

siamesegun
06-05-2015, 5:16 AM
She sprung to life!!!!

I ended up buying the K&N RC-2382 filter pack. It was $80 but they fit like a glove. Main jets went up to 115 from 82.5 and pilot jets went up to 45 from 40. Two turns out on the mix screws as a base line. Once I do some more testing I'll dial it in.

I've got a little lag in the throttle and it hangs after I let off the throttle so I don't think my cables are set right. Might have to come back down to the 42.5 pilot if I can't get the response right.

I decided to switch up to the B9ES plug over the stock B8ES since I jetted up so big but will probably switch back so she doesn't burn too hot.

Hoping Jet will stop by and reeducate me on the throttle lag and if there is a jetting concern with the hanging throttle (if you read this, just make your carburetor shit a sticky already haha).

Pics to come later.

JetBlackII
06-05-2015, 9:16 AM
Last page on the tech forum side is the mecca of carb fixes; http://www.chopcult.com/forum/showthread.php?t=33716 I stepped down from modding, so my sticky is back to ladies only.

Throttle hang... If the cable(s) isn't/aren't binding, slide(s) sticking on a CV type, or a vacuum leak... it's likely running too lean. If the bike shuts down with the A/F screws turned all the way in for an AIR screw the pilots are too big, if it's a FUEL screw when backed all the way out. Air or Fuel screw depends on which side of the venturi/main carb body the slide is in falls on... air filter side, it's an air screw, if it's motor side... it's a fuel screw. If it is an air screw, there is a such thing as a lean bog... usually you'll get nothing on a twist, then it will just take off like a rocket after the flat spot or stumble if it's a lean bog. If it occurs in mid range only, then it's typically the needle at fault. The pissing gas was likely one of your float needles either worn or incorrect float height... some times the pin slips inside when putting them back together, causing the float to hang when it feels like being a pia.

The rule of thumb of up two mains the pilot can stay the same, but up 3 mains the pilot bumps up one... comes from adjustments on the A/F screws from stock under 400cc you can usually skip any carb jet changes as the A/F has enough adjustment to iron out when opening it all up. Normally, when jumping to pods, up two on the main and leaving the pilot alone works just fine on screw top, same deal on CV's but a needle height or float height adjustment is sometimes needed typically 2 #4 washers under the needle, or a 1mm increase in float height from stock height.

You really want to go for a smooth transition between the 3 carb circuits... idle, mid, and wot.

This will help you and anyone else to narrow down what circuit is acting up during the transition;
http://i428.photobucket.com/albums/qq10/jacksonw44/FCRTuningguide.jpg

siamesegun
06-08-2015, 2:13 PM
Thanks so much as usual Jet, I'll check the tech forum. I knew I'd seen a megathread somewhere but couldn't remember where and this forum tends to barely function for posting sometimes let alone search or PM.

Speaking of not getting messaging to work, you still building that Twinstar? I've decided to give up on mine and was wondering if you wanted/needed parts for it.

EDIT: I'm also working through a petcock issue (vacuum currently, thinking of switching to gravity) and a potential oil leak on cylinder #4... so, there's that.