kjh Posted October 14, 2013 Report Share Posted October 14, 2013 So I bought a used motor running on 110octane according to previous owner. I was in the middle of a frame down project and needed to swap some parts, so I opened up the motor just to be sure of what I would be running and this is what I had: 7mm Twister Crank clutch locker 68.5 bore on stock cylinders Not sure of head?not a cool or noss? 38mm Mikuni flatslide carbs running open pods CPI pipes Motor originally built by White Knuckle Racing(don't know much about them) After inspection found some things I didn't like such as a the stock impeller, no shift mods, worn clutch. I did all the shift mods, modded star, shift pro bearing with stock spring, bearing on end Crank, shaft mod. checked crank and had it trued, new shift forks, new clutch, new pistons, honed cylinders. After rebuild compression was 140 and 142 and leak down test was solid (after sealing up intake boots). Bike started on the 3rd kick, ran strong at WOT but missed low to mid and got progressivly worse all over. 1st trip to sand thought i was chasing jetting but turned out i had a bad pingel valve, so I know the motor went lean. Have that issue fixed and now have no start. Figuring I torched it, I checked compression and got 135 on both sides. Checked spark and it is good on both sides. When I pulled the plugs, one of them had a white residue on it? Will try and upload some pics. My thoughts:Compression seems low for this motor running on 110, but it seems it should fire. Possible electrical issue? CDI? What should compression be on this motor? I know not knowing the head and dome size it hard to say but there are no markings on it, must be a custom cut. Need some ideas as I am getting frustrated. Quote Link to comment Share on other sites More sharing options...
okbeast Posted October 14, 2013 Report Share Posted October 14, 2013 White residue could be from leaking coolant into that cylinder. Did you replace o-rings on head? If you don't know the dome size, might want to think about taking some measurements and getting a set cut that you know is good. Quote Link to comment Share on other sites More sharing options...
kjh Posted October 14, 2013 Author Report Share Posted October 14, 2013 I replaced all gaskets and orings and I will definitely check dome size if this isn't something easy. Quote Link to comment Share on other sites More sharing options...
kjh Posted October 14, 2013 Author Report Share Posted October 14, 2013 Quote Link to comment Share on other sites More sharing options...
n2otoofast4u Posted October 14, 2013 Report Share Posted October 14, 2013 That's a wk head I believe. Im pretty sure that entire bike is a wk prepped bike. PM justwannarace on here. He is WK. Are you from Oregon/Washington area? Quote Link to comment Share on other sites More sharing options...
n2otoofast4u Posted October 14, 2013 Report Share Posted October 14, 2013 Looked again. That might not be a wk prepped bike. Quote Link to comment Share on other sites More sharing options...
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