Clownboy Posted February 6, 2015 Report Share Posted February 6, 2015 Hello BHQ in having some issues with my build at the end stages. To explain i have a YFZ/Banshee hybrid nearly complete. The Engine i bought off ebay and was rebuilt with new weisco pistons at stock bore & has coolhead. At first i put on a set of mikuni 28mm flatslide carbs but a riding buddy of mine convinced me to try a Trinity 2 into 1 as it is supposed to give alot of low end to the power band which is what i need for riding the timbers in the midwest. And it would also allows me to run my custom aluminum airbox without alot of extra modifications with a single boot from carb to airbox. I contacted Trinity who refered me to another guy must have been the original designer cant recall his name of hand. Anyways he advised me to start jetting with the following. My carb is a Keihin pwk 35 non airstriker. Jet Needle= DEJ clip in middle. Slow Jet= 45 Main Jet=190 Air/Fuel Screw 1.5 turns out Fuel mix would be 40:1 89 grade pump gas with AMS oil Interceptor. Bike starts up idles good. Has good throttle response. Seems to fall on its face in 3rd gear mid range.. I pulled the plugs and found one side seems to be rich with a black tinge and the other is light light brown/tan and wipes right off to a clean silver plug. Im baffled??? All electrical is brand new. CDI is an adjustable type which i have set on 4. What could be casuing this?? Quote Link to comment Share on other sites More sharing options...
LaegerEliminator Posted February 6, 2015 Report Share Posted February 6, 2015 Have you checked your compression in each cylinder? Have you performed a leak down test? Quote Link to comment Share on other sites More sharing options...
Clownboy Posted February 6, 2015 Author Report Share Posted February 6, 2015 I have not. not even sure how to go about it. Are you suggesting an air leak could cause this condition? Quote Link to comment Share on other sites More sharing options...
LaegerEliminator Posted February 6, 2015 Report Share Posted February 6, 2015 I have not. not even sure how to go about it. Are you suggesting an air leak could cause this condition?Yes, that is what I'm suggesting. Use the search function to find the proper method for both tests. Sent from my DROID RAZR using Tapatalk 1 Quote Link to comment Share on other sites More sharing options...
Clownboy Posted February 6, 2015 Author Report Share Posted February 6, 2015 I will thanks for the tip. Just a hunch but i think there may be a possibility of the head gasket failing. I had my return line from the top rear of the coolhead routed wrong and got some coolant in the cylinders. I caught this right away but still i cannot ignore that coolant got into the cylinders somehow. I have since noticed minute minute traces coming out of the silencers. Could a weak or blown gasket also be the problem? Quote Link to comment Share on other sites More sharing options...
LaegerEliminator Posted February 6, 2015 Report Share Posted February 6, 2015 Yes, the scenario you're describing will certainly cause you issues. Sent from my DROID RAZR using Tapatalk Quote Link to comment Share on other sites More sharing options...
Clownboy Posted February 6, 2015 Author Report Share Posted February 6, 2015 Yep i had a feeling well tomorrow morning going to do compression and leak down test. Likely will be tearing her down again. Thanks for the input bro Quote Link to comment Share on other sites More sharing options...
dave5.0 Posted February 6, 2015 Report Share Posted February 6, 2015 Cool and wires are brand new? Try a few different plugs? Maybe a bad one? Quote Link to comment Share on other sites More sharing options...
trickedcarbine Posted February 6, 2015 Report Share Posted February 6, 2015 EEK Needle...... Quote Link to comment Share on other sites More sharing options...
sleeper06 Posted February 6, 2015 Report Share Posted February 6, 2015 I don't see how that vent line on top of cool head would have gotten anything into cylinders , also when u buy something like a motor your at serious risk. Every motor add you ever see states low hours, fresh top end blah , blah. The fact that you have stock bore still raises a big flag to me, means someone slammed new Pistons in there and I'll bet u they are clearanced wrong and ring gaps are fucked. I have personally seen many fucked up ebay motors come through here, how much did you pay for it? I'll guarantee you still have all stock internals put back in and not a bit of care went into worn items. I build many motors from oem condition they usually take 1000-1500 in parts without labor . My suggestion is stop riding it leakdown test it first to establish good seals /o rings/gasket mating. Compression test to see where your at. Take off head check ring gap with a feeler guage you should have around.012 , I'm betting your off or there original Pistons that are shot Quote Link to comment Share on other sites More sharing options...
dave5.0 Posted February 6, 2015 Report Share Posted February 6, 2015 I just bought an EEK needle I'm not gonna use if ya need it. Quote Link to comment Share on other sites More sharing options...
Clownboy Posted February 6, 2015 Author Report Share Posted February 6, 2015 Thanks everyone for the support you all have raised my attention to the point of dissecting the engine to see what exactly I'm working with. As another member just posted I too was skeptical about buying this motor. I had the opportunity to speak over the phone with the seller before payment was made. He was an older gent and seemed like he had lots of money his 2 sons liked to piss away for him. He told me he had the motor rebuilt and his sons got a hard on for a rz 500 in the mean time and he was just trying to recoop some of his money. I guess he made me feel comfortable. I remained skeptical until today. I got lucky. I first did a compression test came out 125 on a kinda janky gauge but its def been honed and new pistons installed with .12 tolerance. Wsm pistons putting the final bore 65.5 mm 22cc domes in the cool head. Crank seems tight. I guess I'm satisfied with the $1100 I paid. Found out however that cool head stud was missing an o ring just one but it was on the cylinder I have been having lean conditions with and noticing minute coolant dribblet a few times. Also found out that the Trinity 2121 manifold used to have an O ring on the back we're amounted to the cylinder intake ports that's some a****** aground off and sand it down and I'm not getting a good tight seal. Quote Link to comment Share on other sites More sharing options...
Clownboy Posted February 6, 2015 Author Report Share Posted February 6, 2015 So now I've got the manifold getting milled down and also talk to Trinity about the tuning of the carburetor. Harry was the guys name I talk to and he keeps recommending me the DEJ needle that I just got in the mail but I would still not mind trying that ek out and yes I would be interested in taking that needle from you if you're not going to use it. Pm me or I will pm you thanks for the offer. I'm still hard at it over here but I'll let you guys know how it comes out here thanks a lot for all the help. Quote Link to comment Share on other sites More sharing options...
Clownboy Posted February 6, 2015 Author Report Share Posted February 6, 2015 On another note to somebody could please explain to me how to upload pictures or videos I just love to show you my build Quote Link to comment Share on other sites More sharing options...
BUILDER Posted February 7, 2015 Report Share Posted February 7, 2015 Use Photobucket for your pictures that is the easiest way. I would seriously consider loosing the adjustable CDI and going back to stock!! You will chase your tail with those things. Quote Link to comment Share on other sites More sharing options...
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