Sg Jets

[tarzan]

Can anyone with an SG with stock exhaust and a K&N air filter(in the factory airbox) tell me which jets are working for you.My bike is bone stock except for the air filter.I checked my plugs and I'm running lean.I found the threads on recomended jet sizes and I'll try different combinations if I have to.However If there are a couple guys already running my same setup on an SG ,maybe I wont have to experiment much.

[XSPastor]

I've got an SH. Same carbs. I'm running a K&N in the stock airbox. I also have the stock 4 into 2 exhaust. I'm running 110's in cylinders 1 and 4 and 120's in clylinders 2 and 3. Also, 42.5 pilot jets on all 4 carbs. The plugs all look nice and tan. If you only changed the air filter, stock jets should still be fine - or maybe one step larger. Is the airbox drilled?

[tarzan]

Well I thoght I should be able to use stock jets.I'll have to check float height and maybe adjust pilot screws.The bike runs good,when it gets run for a while it starts to act like it's running hot.It will rattle in between 3k and 4k rpmwhen it's hot and is alittle hard to start when its hot.Also ,no my air box is not drilled.The bike only has 1350 original miles on it over 700 of that in the last 2 months.
Thanks for the reply XSpastor

[XSPastor]

With a bike that old with that few miles either the odometer was reset or the bike sat A LOT. If you haven't yet cleaned the carbs that might be a good idea too. Alternately, you could run some seafoam and see if the 3 to 4k problem clears up. That's the rpm range wherer the pilot circuit is handing off to the main jets.

[tarzan]

Yea actually the PO bought it brand new.He must have scared himself on it.He died last year and I bought it from the estate for $400.It was last registered in 1983.I registered it since I got it.
The tires were still like new but rubber was hard,so I changed them.
I completely went through carbs.They are clean and all passages are clear.New needles and seats,o-rings under seats are new,and gaskets.I hadn't drilled plugs out for access to pilot screws though.So I did that last night and put new o-rings on them.I'll fire it up after work today and adjust the screws.

[Lamric]

I added a K&N filter to my LG (same carbs as the SG) no changing of jets was needed.

The factory setup is as described by XSPastor.

[tarzan]

Ok ,I just pulled the carbs and checked the float height and they are all at 23mm now.One was a little high so I adjusted it.
I also finished putting the pilot needle o-rings in it and adjusted them out about a 1/4 turn from stock.Checked timing ,it was right on.and adjusted the timing chain tension.One thing a little strange I found when I took the bowls off to check the floats ,I looked at the mains and they are all 110's.I thought the sg's all came with 110(1&4) and 120's(2&3).However I did my friends carbs on his last week and his had all 110'S too.I thought that was wrong so I put 110's & 120's in his.His does run good.
Well it started raining so I only road my bike around the block.I'll hopefully ride it to work tomorrow if it dont rain and see how it is when it gets good and warm.

[XSPastor]

They put 120's on the inner two cylinders to equalize the temps with the outer cylinders which run cooler due to being on the outside. It would probably run the same with all 110's or all 120's but I would always error on the side of rich.