First Start up since Aug! issues

[Sesty]

started it tonight for the first time since i bought it. needed a lot of carb work. after several cleanings and boilings still could not get the needle jets out. decided to spend a little money and get them cleaned and rebuilt. thanks to Rick from oldskoolcarbs.com they came back amazing inside and out.

rejetted them:
135 Mains and 45 Pilots, 3rd needle position, floats at 27mm and mixture screw 2 turns out from seated

running pods and shortie ermgo mufflers.

started no problem first press off the starter with full choke. revved at around 1800. once it heated up jumped up to over 4k. killed choke it would then sputter out.

while it was warming up, when i gave it gas it would shoot a little blue flames out the right side and back fire as the revs returned.

idle passages are clear as new, should i back out the mixture screws more?

 

[16VGTIDave]

Blue flames from the exhaust is a very lean mixture. A lean mixture burns slowly. The question is "why is the right side lean?". Did you remember to put the cap on the vacuum fitting?

Those are very pretty looking carbs!

 

[Scorpio1963]

2 turns out with pods and emgo shorties is very lean.I would go out to 3 and 1/4 turns and see how she does.Sync the carbs also.
The cleaning job on those carb is amazing.They look like brand new.

 

[Recreateme]

I concur. Its running lean lol

Turn the mixture screws out until its running how you like.

My guess on why the right side is running lean is because you have it on the side stand, and tilted to the left, this would reduce the amount of gas in your right side carb if you happen to already be really lean, so unscrew those mixture screws to at least 3 turns out and fire it up again!

 

[Sesty]

Did you remember to put the cap on the vacuum fitting?

there is a cap on the Left vacuum fitting and the right is uncovered.

My guess on why the right side is running lean is because you have it on the side stand, and tilted to the left, this would reduce the amount of gas in your right side carb if you happen to already be really lean, so unscrew those mixture screws to at least 3 turns out and fire it up again!

Yea it was on the side stand. i will adjust the screws or tomorrow , i forgot to take my battery to get charged so wont start anyway. Plan on getting them synced on the bike soon when i drop it off to have the fork seals replaced.

Rick did a bang up up job on these carbs, they almost look to clean for the bike!

 

[Scorpio1963]

The left side where the cap is usualy connected to a vacume operated pitcock.The right side is capped off.If your running a non vacume operated pitcock make sure both sides are capped off.

 

[Sesty]

its the stock vacuum pet cock... only flows when the bike is off when its on Prime.

the only thing coming from the petcock is the fuel line to the banjo on the left side of the carbs.

 

[Scorpio1963]

If its a vacume operated petcock you would have 2 fittings comin from the bottom of it.You have your gas line and then a much smaller line

 

[16VGTIDave]

there is a cap on the Left vacuum fitting and the right is uncovered.



Yea it was on the side stand. i will adjust the screws or tomorrow , i forgot to take my battery to get charged so wont start anyway. Plan on getting them synced on the bike soon when i drop it off to have the fork seals replaced.

Rick did a bang up up job on these carbs, they almost look to clean for the bike!

Don't touch those carbs just yet! Put a cap on the right vacuum fitting, and connect a short vacuum line from the left fitting to the petcock. Then you can report back as to how well it runs. And how cool it is to have a petcock that is "auto-magic" in the run position!

 

[Sesty]

i will inspect closer tonight. thanks for the input. the bike has only had one owner and 7k. but who can know what they did.


i forgot to mention in the original post... After turning the bike off, there was this pinging sound coming from what sounded like the headers. it made the noise randomly but regularly. Is this just the metal heating up and expanding?

 

[16VGTIDave]

I'd guess those noises would be the exhaust cooling off after getting very hot from running lean. It is "normal".

 

[Scorpio1963]

Note since your running pods with emgo shorties the mains you have are way too small,this will cause an extreme lean conditions also.I suggest either going back to stock air filters and boxes or rejet the carbs.Iwould go up 2 jet sizes on the mains for the setup you have.I also suggest that you don't run the bike until you get the air to fuel mix corrected as its very possible you can burn a hole in the pistons.

 

[Sesty]

135 mains are still too small? it was shooting flames under 4k, isnt that still in the pilot jet's range? what should i go up too?

my petcock is not set up like the one pictured above.

It looks like PO rebuilt the petcock and installed the diaphragm cover on with the tip facing up. then covered the left vacuum and ran the vacuum hose from the petcock up and around the frame along the tank to the the other side but the hose wasnt long enough to reach the now exposed right vacuum line. which is why i didnt even see a hose hanging off the petcock.?

i took the tank off routed the hose straight down on to the left vacuum line and covered the right side with the plug.

ill need another set of hands or eyes tomorrow to make sure the hose is not pinched anywhere as the angle is a little weird and its around the frame.

 

[Sesty]

front view of Petcock wouldnt upload

 

[Scorpio1963]

The pic I posted was from an xs650 it was just an example of how there is 2 different size lines coming from a vacume operated petcock.Your bike is a 79 sohc not sure what size jets are stock for that year but they seem small for the mains for the ehaust and pod setup you have.Im guessing the reason your bike is shooting flames out the exhaust I because your still running lean.My 81 used a 137.50 main jet and I had to go up 3 sizes b/c of my filters and open exhaust I had at the time.My pilot was a 42.50 and I went up one size on it.My air fuel mix screws are 3.25 turns and it starts as soon as I hit the estart.

 

[Sesty]

yea when i get the battery back and get some time, i will back out the mixtures screws to 3-4 turns out, already hooked up the other tube from the petcock. i will see how it runs like that, if its still running too rich will have to rejet again to larger mains.

im not having any issues starting it which is a win for now

 

[xschris]

Mains will only affect 3/4 to full throttle operation.

 

[Scorpio1963]

Not sure if you meant still running to leanThen you will need to rejet if its running rich then leave the jets alone

 

[Sesty]

yea i mean lean ^

 

[xschris]

Have you synced the carbs yet?