cant get bike to run, gas ending up in the oil.

j_dubbb

XS650 Enthusiast
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Ill start from the beginning. I bought this bike as a stock 1980 xs 650 special and i was 19 years old. i originally went with the brat set up from visual impact because i planned on this being my daily rider and my old man thought a hard tail would be to much as a daily rider. I installed a pma and a pamco on the bike and everything was coming along. About halfway through my dad suffered a heart attack and passed. I am not by any means mechanically inclined so my god father stepped in to help. we got the bike running with unipod filters, stock set up bs34 carbs and open pipes. i took the carbs off and have had nothing but problems since. I rebuilt the carbs and made some adjustments on the jets from recommendations from mike over at xs650 central. as soon as they were back on the bike it wouldnt start. I had bought another bike so this isnt going to be my daily rider so i went a head and hard tailed the bike, rewired it myself and even threw the electric start back on. i figured i would just start fresh with some vm34 carbs. the carbs have the correct float height, 6F9 needle, P-6 Needle jet, 185 main jet, and a 25 pilot at the moment. i can get the bike running momentarily but with white exhaust coming out of the pipes with oil (and gas?). I can sit there and WATCH the gas go down on the sight gauge. The engine has 120 psi on each side for compression so i figure the rings are ok. I believe my gas is going to the oil somehow because the oil smells like gas and the oil level goes up. I adjusted the cam chain, valves (.002 inlet, .004 exhaust) and set the timing (in that order) and none of this solved the problem. Im at a complete loss and tired of dumping money into this...... Any ideas what the issue is?:banghead:
 

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Is it possible to have good compression but gas still pouring past your rings into your oil? That's a question for the experts on here, but from your description, I wouldn't be trying to start your bike with the current situation, sounds like you could blow your motor up and need rebuild, if you don't already.
 
There are three main ways to get gas in the oil. Overloading your floats thru improper adjustment or sticking, and timing so retarded you aren't burning all your fuel. That lets a lot of gas get past the rings. Check the float on the rich looking plug carb to see if it maybe has a brass float that is holding fuel. Very common, that. If all that seems ok you may have a needle failing to seat properly.
 
They are plastic floats and are adjusted and double checked. The timing was way off but has been corrected. The needles should be operating fine. I had the needles needle jets and mains all out today and cleaned and refit them.
 
No air jets. And the I'll have to check the plugs. Took those pics the other day but one had more oil than the other
 
I'm going to do an oil change and throw in some fresh plugs and see if I can get better results. I guess I'm wondering if I get the same results , am I looking at a rebuild?
 
I never trust the needles, I verify how much gas is actually in the float bowls. I will play with them on the bench using the hose up the side method when possible. A clear hose from the bottom of the float bowl, turned up past the side of the bowl, and gas will fill to the exact level as that inside the bowl. This is easy or hard, depending on the carbs. You have BS34's I assume, and I'm not recently familiar with those, but I bet somebody in here can tell you how to verify the amount of fuel when the floats are up. I do not trust the needles to seal or stick measurements of float height. I want to know the actual amount of fuel in the bowl, because that's the only thing that really matters.
 
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