Pilot jet advice pls

[Qdude]

81 GS 750 E

4 to 1

switched to pods

which pilot jets should I get?

 

[Guest]

Go up one step
EX 40-42.5

 

[Qdude]

So I should get 42.5 jets? The "EX" leads me to wonder what you are offering...

Sorry, the answer to posted situation for a 77z650 is 17.5. I was hoping someone would know which work most often for a 81gs750. I'll just go and take them apart and have a look.
Cheers

 

[Turtleface]

So I should get 42.5 jets? The "EX" leads me to wonder...

Sorry, the answer to posted situation for a 77z650 is 17.5. I was hoping someone would know which work most often for a 81gs750. I'll just go and take them apart and have a look.
Cheers

The EX is just a model and year indication The E is for chain drive, and the X indicates model year 1981. According to Basscliff's PDF service manual, the stock size is 42.5, which means one step up should be a set of 45s. Chef's usually pretty damned spot on with his carb recommendations.

It seems as though you haven't had these carbs apart, else you'd know what the stock size is. Do yourself a huge favor, and spend the time and money to rebuild them properly. You'll need a can of Berryman's carb dip, and a o-ring kit from Cycle O-rings.com. Maybe 30-40 bucks all said. The pilot jets might run you another 12-15 bucks for new ones. Without the carb rebuild, you'll have a hell of a time TRYING to tune it. These things are pretty sensitive to bad o-rings in a stock engine, even more so in one that's modified as yours is.

 

[Qdude]

Yep, already bought a set of 45's. Went out and took the carbs off and pulled one float bowl to confirm the size. Also rechecked the parts I pulled out.

Turtleface, the EX I was referring to was the EX from chefs post.

For the record;
Each carb has been dipped for at least three days (all non metal parts excluded of course), blown out with compressed air & inspected for wear and blockage. Non metal parts have been cleaned with carb cleaner & old toothbrush (yes, toothbrushes fall apart in solvents) and inspected for wear. All jets have been replaced with new of the same size, 42.5 pilot, 112.5 main, & 170 in the rear. All gaskets have been replaced. All float levels have been simultaneously confirmed/inspected via clear tubing threaded into the float bowl drain. Butterflies have been bench adjusted (one had been sticking). And, I have a set of plastic main jets that I use for testing out new setups once I get the pilots closer.

O-rings, fortunately I did not need them. No fuel leaks from the fuel couplings so far. The intake manifolds are so far not sucking-air/sound as well.

Once again, this beautiful bike, is not mine. An abused un-maintained wreck to begin with, it was presented to me dis-assembled and woefully incomplete.

Now it has a freshly painted tank (1/4 cup of body filler over prior repairs, a weld or two for hole found, BB's in the tank rotated for four hours to knock out the flake, water flush, miuriatic acid rinsed, vinegar rinsed and honing oil coated, plus a petcock rebuild) custom built seat, total rewire, brake overhaul, carb rebuild and safety checked. I rode it this week, all good...

Sorry for the lack of detail in the post, I was trying to stick to the basics to see if it would get results. I am used to the culture of another site where the guys race to be the first to help. This and my other post asking for jet size help came up goose eggs

http://www.thegsresources.com/_forum/showthread.php?t=161773

Though I am going to replace the seals myself now.

Sorry to ask that simple jet question, but you guys know these bikes better than I. Just looking for a jet size hookup from the pro's before I headed to the shop.

P.S. The computer argues with me about recognizing my camera. I need to get my friends to download them and E-mail them to me. Hence the delay in getting pics posted.

 

[Qdude]

There are O-rings on the needles !!!

Turtleface, are those what you were referring to?

Got it.

 

[Turtleface]

Yep, already bought a set of 45's. Went out and took the carbs off and pulled one float bowl to confirm the size. Also rechecked the parts I pulled out.

Turtleface, the EX I was referring to was the EX from chefs post.


O-rings, fortunately I did not need them.

An abused un-maintained wreck to begin with, it was presented to me dis-assembled and woefully incomplete.

I was referring to the same EX, Chef was just prefacing the jet size with the model indicator.

The bold bits there, that indicates a distinct need for o-rings. Mine didn't have any air leaks, or fuel leaks either, but dry, brittle thirty year old o-rings that have been subjected to all sort of fuel, and then left to dry out, definitely need changing, no question about it. Good example, friend of mine was the original owner of a honest-to-goodness Skunk. Bike was built. He gave it to his son. Bike developed a fuel leak, via a bad o-ring. Unfortunately, it burnt to the ground. Loss of a brilliantly built survivor, for lack of less than a twenty. Good job on the dip though, most people try to short change that bit. Get the owner to pony up the $14 bucks (SHIPPED!) that Robert Barr charges for every single o-ring you need. It's impossible to find a better deal. You said yourself, the GSR community knows these bikes better than you, trust us on this one.

 

[Guest]

ex=example
Sorry for the confusion.

 

[Qdude]

Confusion is good for exercising the problem solving skills .

 

[koolaid_kid]

ex=example
Sorry for the confusion.

Thanks. I thought I was the only bozo on this bus (firesign theater reference). That is what I thought you meant, but then Suz's nomenclature was explained, and I said "huh".

 

[posplayr]

Thanks. I thought I was the only bozo on this bus (firesign theater reference). That is what I thought you meant, but then Suz's nomenclature was explained, and I said "huh".

I had no Idea what the two letters mean

 

[Turtleface]

That was my fault, it seems. I saw 81 E in the OP's comment, and my brain immediately associated that with the EX in Chefs post. That's the parts monkey in me talking.

 

[Guest]

I was driving the bus.