Uh OH.... I think I lost a piston ring?

[Jedz123]

www.ronayers.com is where I sourced a new valve needle. it's $45 for the valve needle assembly(Suzuki OEM). I found cheap needles but they were for an 1980 GS400E, don't think it will work. Where did you get yours Combat?

I left the gas on once by accident and gas slowly leaked onto the floor over night... Bad habit I guess for my other bikes have vacuum controlled Petcocks. I turn it off now every time but still the problem persists...

 

[TheCafeKid]

First of all, check Z1 for float needles. 6 pack for way cheaper than $45. That's highway robbery. If they're grooved, they won't seal. I'd sniff your oil too, if it's gassy, you've got issues. If enough gas is in the oil, it will thin it out to the point that it will pass the rings and valve stem seals. I recently had a buddy bring me an ATV (600cc single THuMP!) that he thought had bad rings. After stripping the top end down, checking specs on everything, I found that the rings were well within spec. But the first thing I noticed was that the crank case was crazy full of gas. Like over the crank full. When we pulled the drain plug it gushed like a waterfall, filling my 2 gallon drain pan full.
I surmised that the problem was indeed that, oil was so thin it was passing the rings. I put new valve seals in, kept the rings, put it all back together, rebuilt the carb and replaced the non vacuum petcock (they do go bad too) and she ran like a champ.

Check it out. Gas in your oil is bad bad news. It can wash the bearings and cause all sorts of expensive issues.

 

[850 Combat]

I don't remember where i got mine. They came with a carb rebuild kit. It had the entire valve.

 

[Jedz123]

Thanx HoligAn for the info. I drained the oil a couple of weeks ago after discovering where my gas was leaking too(crank case :/)... The neddle valves are grooved for sure! ill check Z1 for new ones.

 

[TheCafeKid]

Hey brother something else I thought of that, if you're sure your not dumping fuel into the cases and you still have issues:

Your bike still running points and condenser ignition?
If you have a condenser that's gone bad, it won't fire worth a crap. Sporadic at best if at all. The mess you may be seeing on the plug from that cylinder may simply be unburnt/poorly burnt fuel residue (if you leave the plug out and it evaporates after a bit and doesn't remain shiny and wet and black, it might not be oil)

An Aussie member we had visit us last season had this similar sounding situation. Bike, when cold, ran like a champ, but that condenser once it got hot would take a dump and it would drop a cylinder. Let the bike cool and it would run on all four pots again for a bit.

I'd check that out as well if you still end up stuck.
If your float needles are scored, I'd still replace them, but I thought I'd throw this out there as well...

Good luck!

 

[850 Combat]

I once owned a Triumph that would lose spark after about 30 minuits with an intermittant short in the coil. My first car, a 'Renault Dauphine, had a bad condenser that would allow it to run perfectly until it had a load, then it would misfire.

Hey brother something else I thought of that, if you're sure your not dumping fuel into the cases and you still have issues:

Your bike still running points and condenser ignition?
If you have a condenser that's gone bad, it won't fire worth a crap. Sporadic at best if at all. The mess you may be seeing on the plug from that cylinder may simply be unburnt/poorly burnt fuel residue (if you leave the plug out and it evaporates after a bit and doesn't remain shiny and wet and black, it might not be oil)

An Aussie member we had visit us last season had this similar sounding situation. Bike, when cold, ran like a champ, but that condenser once it got hot would take a dump and it would drop a cylinder. Let the bike cool and it would run on all four pots again for a bit.

I'd check that out as well if you still end up stuck.
If your float needles are scored, I'd still replace them, but I thought I'd throw this out there as well...

Good luck!

 

[Jedz123]

Thanks guys I plan on buying new needles soon. I go on thanksgiving vacation starting Friday (gotta love being a UVM employee) I plan on trying to source some new needle valves in the mean time. Then actualy get it working over the break. The B-12 sprung an oil leak on the starter gear cover and that took up my time rsourcing and replacing that gasket. Gotta make sure the daily runner can still run I suppose!
I'll keep my eye on the spark issue but I know when I pull the plug and check it; even hot, it will still arc strong.
Thanks again!