arh Posted April 24, 2009 Report Share Posted April 24, 2009 Hi good people! I've had my bike for a while, but now it has been sitting for over a year (school abroad). It's a '99 Cota 315R with a lot of 2004 (or so) upgrades. When I parked it, it had some minor issues with the clutch, but now it's straight useless. It doesn't disconnect at all, when you put it in 1st with the clutch engaged it literally takes off. I tried bleeding with no luck. Secondly, there seem to be a fair amount of oil seeping from the underside of my engine. How should I go about to take care of this, do I have to split the whole engine and change the gasket? At the risk of sounding like a complete n00b, would this be motor or gear oil? Or do they share oil? Is that the plastic fill plug on the right side? Lastly, my bike is probably in due time for a little tune up. What kind of spark plug, oil(s), coolant, air cleaner, brake pads, etc. are recommended? Thanks a bunch! Quote Link to comment Share on other sites More sharing options...
arh Posted April 26, 2009 Author Report Share Posted April 26, 2009 WTF? What happened to the replies that were here yesterday? I disassembled the bike yesterday and cleaned some stuff up. The oil residue almost looks like normal motor oil (translucent amber). I found the tube that goes around the carb (from each side) was torn. Could this be the culprit? Also, are there two vent lines from the crankcase and gearbox? Is one supposed to go into the frame? Where's the drain plug for the gearbox? Are there some way of calculating the amount already in there, or do I have to do a complete drain and fill-up? What color is the ELF stuff that's supposed to be in there? I have some Dexron III ATF, is that a go or a no-go? Quote Link to comment Share on other sites More sharing options...
arh Posted May 5, 2009 Author Report Share Posted May 5, 2009 Gear oil: OMG, I was shocked to see the what looked and felt like black water pour out of my tranny! I flushed it out with some gasoline, and gave it a fresh load of Dexron III ATF (mineral oil). What a difference that made! Stuttering: After being able to ride a little around, the motor has developed a stuttering kind of behavior. All of a sudden it lacks power and "puffs" more than usual. And equally abruptly it disappears and function normal. I swapped the tank for a different one, could there be remnants clogging the filter? Time for a new spark plug? Oil leak: I was trying to trace down an oil leak I believed to be gear oil. It obviously is not. The oil is dripping from the carb onto the gearbox housing. I believe this is due to the superfluous oil/fuel mixture. But still, why is the oil getting out? I have the Dellorto PHBH26BC with one adjustment screw. There's a hole to the left of this screw, could it be coming out of that? I have always been running 2% (50:1), because I was told this was within spec. No wonder oil is always dripping out of my silencer, huh? Quote Link to comment Share on other sites More sharing options...
tt5th Posted May 6, 2009 Report Share Posted May 6, 2009 Hi, Glad you got your oil change sorted. For thes rest I would change the spark plug and clean the carb. Usual mixture is 80:1 (63ml of oil to 5L of petrol), running with 50:1 mixture is likely to have fouled the plug. Carb should be cleaned as sitting for any length of time the petrol can evaporate and 'gum up' the internals. Make sure you air filter is sparkly clean to, fairy liquid works well! All that said I still foul my plug at 80:1 and have oil dripping from my silencer Somethings a little rich somewhere I think, going to experiement with needle position and see if I can make any headway. Will let you know if this sorts it. Cheers, John. Quote Link to comment Share on other sites More sharing options...
arh Posted May 9, 2009 Author Report Share Posted May 9, 2009 Yeah, I'll do another oil change fairly soon. I'll buy a factory spec plug and see what difference that makes. Will run a less oil rich mix in the future for sure. This is an "environmental friendly" premix purchased in 20L drums. From now on I think I'm gonna buy Shell's 99-octane V-Power and mix in the synthetic 2-stroke oil myself. Any word in that extra "hole" in the carb? The drawings I have both show two adjustment screws. Let me know for sure! Quote Link to comment Share on other sites More sharing options...
tt5th Posted May 9, 2009 Report Share Posted May 9, 2009 I have a different model carb, a CS apparently. 2 adjustment screws though. Quote Link to comment Share on other sites More sharing options...
arh Posted May 10, 2009 Author Report Share Posted May 10, 2009 I grabbed a pic of the carb: Quote Link to comment Share on other sites More sharing options...
tt5th Posted May 10, 2009 Report Share Posted May 10, 2009 Yep thats right, you have the two screws, the hole is just a hole. Its not threaded and is closed at the other end so nothing goes in it. Must be something to do with the casting process i guess. Quote Link to comment Share on other sites More sharing options...
arh Posted May 11, 2009 Author Report Share Posted May 11, 2009 Gotcha! You can kinda see the marks from the seepage. Looks like it could be coming from the main adjusting screw? Quote Link to comment Share on other sites More sharing options...
tt5th Posted May 11, 2009 Report Share Posted May 11, 2009 Either that gasket or the main one that sits between the two halves. Should be cheap enough from Sandifords. Quote Link to comment Share on other sites More sharing options...
fastducs Posted May 18, 2009 Report Share Posted May 18, 2009 Big screw (the one in the middle) is the throttle stop, i.e. idle speed adjustment. The small screw on the right is the pilot circuit air screw. If memory serves me right, both screws should have rubber o-rings to help seal the threads. Normally you first fit a spring onto the screw, then a small metal washer, and finally the rubber o-ring (so the o-ring ends up deepest in the carburetor). The seepage stains look like they come from the throttle stop screw, or maybe even all the way from the top of your carburetor. BTW, the vent tube doesn't look stock. It's the black tube at the top of carb angled towards front of bike. Normally it is a thin black tube that connects both vents, and has a slit opening at its lowest point. Yours has some sort of thick rubber hose going over the stock vent tube. Not that there is anything wrong with that, as long as it doesn't cover the slit. The two crankcase breather hoses are both supposed to go into the frame. There are 2 holes drilled on the inside of the frame next to the carburetor. Quote Link to comment Share on other sites More sharing options...
arh Posted May 20, 2009 Author Report Share Posted May 20, 2009 Thanks for clarifying. Yeah, I can explain the rubber hose. Before looking at any drawings when I had the carb apart, I thought: "Hey, a gash in the tube, no wonder it leaks!" Long story short, I now have a slit in the tube. I still think I should get some kind of filter element at the end of the "sub-air cleaner tube". Any suggestions? Quote Link to comment Share on other sites More sharing options...
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