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First post on here and I just have a question on the cam timing and how bad it has to be out for valves to kiss, anyways first of all the quad wasn’t starting, so after doing research for all of 15 minutes I had decided on valve shims being the cause, went to the manual and screwed up calculations thinking I could(I know this is dumb lmao) just swap the exhaust and intake shims and be set, while doing so I installed the cam tensioner without winding it up, making it super tight, and also I retarded the exhaust cam by 1 tooth, and it started, only ran it for about three seconds because it was knocking(I’m pretty sure this was so to the cam tensioner) and after figuring out I needed to wind it up the tension was back to normal I also re advanced the exhaust cam to where it was supposed to be, I’ll explain how I made the cam timing mistake later, and the knocking was gone but it was still running odd, not running perfect, I then rechecked stuff for about a week and determined that I made a big mistake on my calculations with valve shims stupidly and bought the right ones and rechecked and got them actually in spec, and it runs perfect now but I have noticed what most call the predator tick, this was all months ago but I just am wondering if I should do a tear down before season and before anything else could be damaged if this did damage something and it breaks while the engine is running and causes a major headache in the middle of the woods, anyways now for how I made these mistakes lol, I aligned the 9 o’clock marks instead of the 12 o’clock marks, therefore aligning the intake but retarding the exhaust, I now know to always check where it’s at when screwing around, also to check that the crank sprocket has not skipped a tooth and made the chain all wacky and not to the right alignment, basically inner links of the chain are where outer links are supposed to be, also could cause it to slightly rotate the crank just enough to get it off tdc so you gotta either secure the crank or not fiddle with the chain too much and get lucky. But it runs better then it has in a long time, wants to wheelie now, I’m pretty sure it’s getting awesome compression, starts up almost instantly, runs good temps, sounds good and the only odd thing is the idle fluctuates a little, not erratic just jumps up and down every few seconds making it not sound like it’s idling smooth I have went through the carb and got rid of the air leak from the o ring under the pilot screw, it was cracked and leaking tons of air this made it idle better, but not the perfect tip top idle I’m hunting, and with the tick I’m thinking it’s still a top end issue, I either think it’s cam tension, a stretched chain, a combination, or something got screwed up on the valves but idk seeming as the valves were all loosey goosey with shims swapped and I’m guessing that it kinda counteracted my cam mistake, but it was knocking I know for sure from the tensioner, but it could have been the valves as well being hidden, but after figuring out the tension and cam position the knock went away because we turned it over without a spark plug to check all was good throughout this, also compression came back fine, I didn’t check specs or anything but i know it wasn’t losing a ton of compression because with my jank set up I checked it before I started working to get a baseline, I need to get a real tester to check it and I also need to leak down it, I did get a vacuum tester and checked that tho, and it’s fine which makes me think that compression is fine since it’s pulling a good vacuum and makes stupid good power now that I have the valves in spec and the tension was reset and I have the cams in time. Also took my plates from behind the tip off the pp exhaust for current spring riding and it has such a good power range, still has the low end, the top end is opened up like insane now and the power rolls in like crazy, I’ll post my carb setup sheet when I get home and I’ll also check and post the valve tolerances at some time might be next week depending upon what I get response wise, I’m going to check my spark plug when I get home too, that could be fouled with all my carb tuning and coming out of winter with the choke being left on for too long one too many times probably. Thanks for all who reply and this seems like an awesome place!!!
 
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