economical jetting...or alternative to dynojet

[Guest]

Long story short - picked up a 82 GS650GL last spring, has a 4 into 1 exhaust and pods. The fellow said he had cleaned the carbs and rejetted it - took him at his word. Ride home seemed to run good - smooth, and good power - better than the 81 GS650G that I had. Did appear to run a bit lean/hot.

Anyways, the bike was for my wife, spent most of the spring getting brakes to work correctly, lights, etc. Decided to replace the O ring gaskets on the intake boots...good call, as they were original. Buttoned it up took it for a test spin, and it appeared to be running pig rich...like can't keep it running pig rich, turning the choke had no effect or made it worse. Another long story short - decided time was of the essence, and needed to get my wife on a reliable bike, so we bought something newer, with FI etc.

At this point, just want to get it running decent so I can sell it in the spring. My original thought processes was that it was over jetted to compensate for the leaky intake O rings. So I pulled the carbs a part today (they did look clean with new gaskets so PO seemed to be telling the truth about that) and pulled out the main jet and the idle jet...and guess what they were stock. 115 main and a 42.5 idle. WTF? Okay, doesn't explain why the bike appeared to be running pig rich, but figure I should get it rejetted for it's current setup (going back to stock isn't an option as i don't have the original exhaust....I asked they PO if he still had, but he had pitched them.

Did some more digging on this site, and it was recommended to get a stage 3 Dynojet kit.... since they want $125 for the kit, I was wondering if there is a more economical way to rejet - could i order just the main's and idle - does anyone know what the cost for this would be, and would it work? Any other suggestions?

[Nessism]

Simple google search will turn up numerous vendors that sell Dynojet kits so you can get the price that way. Most likely it will cost more than installing a stock airbox though.

If your bike has some crappy Emgo pods or similar then the stock airbox is doubly recommended. If you have real K&N's though, a jet kit is a viable path.

Oh, and the running rich business is because something is wrong inside the carbs. Most likely one of the floats is sticking. It's always best to measure fuel level in the carbs, not just measure float height. This is doubly important if the springs in the float needles are weak (very common).

Good luck

[quexpress]

At this point, just want to get it running decent so I can sell it in the spring. My original thought processes was that it was over jetted to compensate for the leaky intake O rings. So I pulled the carbs a part today (they did look clean with new gaskets so PO seemed to be telling the truth about that) and pulled out the main jet and the idle jet...and guess what they were stock. 115 main and a 42.5 idle. WTF? Okay, doesn't explain why the bike appeared to be running pig rich, but figure I should get it rejetted for it's current setup (going back to stock isn't an option as i don't have the original exhaust....I asked they PO if he still had, but he had pitched them.

It is possible that the PO had the OEM jets drilled.

[mhobryan]

Thanks Nessism! Got lucky and found both parts of the air box on flea bay for $23 shipped. I would agree on the stuck float suggestion, however, when that has happened to me before I usually have gas pouring all over the place b/c the needle isn't seated - didn't have this this time - but who knows... Will check all floats and levels since i have the carbs out.

@ quexpress - I pulled the jets and examined them - I don't see any signs/evidence of molestation/drilling.

[Sci85]

Pods would make it lean not rich so that doesn't add up.
Have you checked for a good, fat, bright spark?
I'm assuming your plugs are black and sooty right?

[mhobryan]

It was running lean (with pods) up until I replaced the intake O ring gaskets (with pods) and then it ran super rich for the one ride (really unrideable...felt very fortunate to get it back in the driveway). As someone suggested, I think that I float may have been stuck causing it to run rich. The pods on it are the junky cheap ones, so was VERY happy to find both parts of the airbox on flea bay so cheap. I still have the 4 into 1 header which will make it run lean, however, everything I've read is that the pods have a more profound impact on the air/fuel mixture than the exhaust.

As far as the plugs, two looked lean, two looked rich (sooty). Will clean and recheck after the air box is installed.

[nikosg]

Have you tried "6 Sigma Racing" on ebay?

im very curious to try them out. reasonable price and from what i read pretty good.

[Steve]

There is more to a Dynojet kit than just a few main jets.

The part that makes it worth the price is the different needles.

You can get new main jets for just a couple bucks each, but you can't find similar needles anywhere else.

.