different pilot jets will they work?

[dfinnegan71]

Hi there, 1st let me say this site is great! you guys have been super helpful.
Check this out. I have been working on a GS 550 from 1980. The carbs were a mess the tank completely rusted. I dipped the carbs and have been cleaning them up as best I can. My problem is that two of the 4 pilot jets were striped so, I thought I would back them out and replace with some new ones.
So I bought a couple off the internet that I thought would work. The ones I received DO NOT have the little holes on the side. They fit right in there real nice. What are those little holes for anyway? Do you think they will work?

[Bonehead]

Where did you get the jets? From my research you should have Mikuni VM22SS (click here for your manual if you don't have it already)

If you look carefully, the ones with the emulsion holes have the actual "jet" at the top versus the bottom of the plain ones. IIRC.
I think that they can be interchanged.
The ones with the holes are for carbs without the pilot jet plug on the bottom and feed out of the internal tube.

Now, I am no expert so I would wait for one to come along. Maybe they are the wrong jets or simply updated versions of the old ones. I don't know if you should run the bike with those jets though.
BTW, why did you only get two? I would just replaced all of them since they aren't that much and can drastically change the performance.

[dfinnegan71]

I only got two because I only had two damaged. I guess I didnt realize replacing the good (non-stripped)ones would make any difference. Maybe I'll wait, your right.

[ben2go]

Your bike came with air bleed style(with holes) pilots.Non air bleed style(without holes) will cause running issues.At idle and low throttle operation,the bleed style jets mix air in with the fuel for better fuel emulsification and better fuel burn.With non bleed style the bike can have a tendency to run rich at idle and low throttle operation.This can cause a number of problems but mainly excessive carbon deposits on pistons/valves,bad fuel economy,hard starting,fouled plugs,and hard starting in certain weather or elevations.This is my understanding between the differences.Someone else my have a better explanation.Either way,your carbs were designed to work most efficiently with the air bleed style pilots.I'm not saying that the carbs can't be retuned to run the non bleed style, but why go through the hassle.

[dfinnegan71]

Oh I see. Thank you for dropping some knowledge on me. I guess I will wait and get the right ones

[Steve]

From my research you should have Mikuni VM22SS

...

Now, I am no expert ...

Sorry, but the "no expert" line is very correct. With a 1980 bike he will NOT have any VM carbs on his bike, they will be BS32SS.

.

[ben2go]

Oh I see. Thank you for dropping some knowledge on me. I guess I will wait and get the right ones

You're welcome.I hope the rebuild goes smooth.There's a lot of helpful info here.

[Bonehead]

Sorry, but the "no expert" line is very correct. With a 1980 bike he will NOT have any VM carbs on his bike, they will be BS32SS.

.

What can I say? At least there was the disclaimer

[ben2go]

What can I say? At least there was the disclaimer

That is all that is needed.

[dfinnegan71]

Just an update for you guys who helped me out. I decided to keep the stripped pilot jets in there and not put the jets I got on Ebay without the air imusion holes in there. I dipped the carb bodys and all related parts in the carb dip over night, cleaned them with carb cleaner spray through all passage ways and wiped em down real nice. All back together and today re-installed on the engine. I put some fresh gas in my little make-shift gas receptacle and hit the starter. The 1980, sitting since 1995, GS 550 roared to life!! thanks for your help fellas!

[ben2go]

Congrats.Good to hear.Now it's tuning time.

[brownford]

Your bike came with air bleed style(with holes) pilots.Non air bleed style(without holes) will cause running issues.At idle and low throttle operation,the bleed style jets mix air in with the fuel for better fuel emulsification and better fuel burn.With non bleed style the bike can have a tendency to run rich at idle and low throttle operation.This can cause a number of problems but mainly excessive carbon deposits on pistons/valves,bad fuel economy,hard starting,fouled plugs,and hard starting in certain weather or elevations.This is my understanding between the differences.Someone else my have a better explanation.Either way,your carbs were designed to work most efficiently with the air bleed style pilots.I'm not saying that the carbs can't be retuned to run the non bleed style, but why go through the hassle.

So are you saying that of the two different pilot jet types, one needs to be used the a rubber pilot jet plug and the other does not? I am dealing with this very issue right now. The carbs that came on my bike had the rubber plug, and I bought a spare set of carbs for parts and they do not have any jet plugs. At first I thought someone left them out, which may still be the case, but since doing a little research I'm not sure.

[ben2go]

So are you saying that of the two different pilot jet types, one needs to be used the a rubber pilot jet plug and the other does not? I am dealing with this very issue right now. The carbs that came on my bike had the rubber plug, and I bought a spare set of carbs for parts and they do not have any jet plugs. At first I thought someone left them out, which may still be the case, but since doing a little research I'm not sure.

I haven't had a set with plugs so I'm not sure.I know the original non bleeder jets don't seem to have issues without the plugs.It's been a while since I have had my hands on an older set of carbs.

[brownford]

I haven't had a set with plugs so I'm not sure.I know the original non bleeder jets don't seem to have issues without the plugs.It's been a while since I have had my hands on an older set of carbs.

After soaking a pilot jet with WD40 in one of the spare carbs it broke loose and came out. It has holes in the side just like the pilots in my carbs. Either: a)someone pitched the pilot plugs in these spare carbs, b)mine doesn't need plugs but has them, or c) there is some other unknown difference between the carb racks. Visibly they look identical.

[ben2go]

After soaking a pilot jet with WD40 in one of the spare carbs it broke loose and came out. It has holes in the side just like the pilots in my carbs. Either: a)someone pitched the pilot plugs in these spare carbs, b)mine doesn't need plugs but has them, or c) there is some other unknown difference between the carb racks. Visibly they look identical.

There are a few different bikes that use the same rack of carbs with nothing more than different jetting.The carbs could have come from a different year or model bike or rebuilt with incorrect parts that fit.I know many people that live by the moto,"if it fits,use it."I'm by no means an expert on the older GS.