QuestionQUESTION: Good morning, I a small shop in texas and we have a 2003 heratiage softail. custumer brought me screamin eagle twin-cam big bore kit,and piston-kit,ajustable pushrods, S&S gear drive cams sys kit.part # 570G. hayden M6 automatic chain tensioner sys. I have 20 years exp on repairing harley davidson, grad from mmi as well. installed all componece with no problems, and started break-in period.I drove the machine 45 to 65 miles not going above 15 to 2000 r.p.m's max, and no speed's over 50 mph and changed oil&filter.custamer picks up bike,giving instructions on break-in. He returned folling afternoon with LOWER ENGINE NOISE-like almost a grinding noise from primary side and cam side. only does is when motors hot,and at lower speed and when your declerating. he said, when he went to get fuel sys remaped, thay put the bike on the DYNO-MACHINE,can you beleave that sh$#@. also said thay did'nt take it above 2500 rpm!! yea right.. I thought maby floted a cam bearing,so i check it. everything looks good. do you think it could be the throw-out bearing? this one's got me stumped, please help us out the best you can.thanks very much, Corey Lipsey Rixs motorcycles, helotes texas 210-695-8706.
ANSWER: A noise from both the cam side and the primary side sounds more like a bottom end problem or a piston problem. I would start by removing the top end and checking the pistons as well as looking for up and down play in the rods. Might have had a bearing go out in the rods.
I find it hard to beleive that when he had it dynoed they never went over 2500 RPM! How did they do any mapping over the 2500 RPM then.
Good luck and happy riding
Mike
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QUESTION: hay mike, thanks for writing back.when i said both side,it's more primary side.I'v checked comentery sprokets,chain clutches and basket.I also ofcourse changed wrist pins and bearings, rod bearing play is fine,and whut are the odds of those bearing going out right when we do a topend. whut do think, could the throw out bearing go bad cause i changed that tentioner on the primary.
AnswerIt can't be ther throwout bearing. That would be on the right side of the bike and when that bearing goes out you start losing the clutch lever.
I would take the bike and ride it. When you hear the sound, pull the clutch in and let the bike coast. Also, get up to speed again and when you hear the sound, pull the clutch in and shut the bike off. If you still hear the sound with the bike off, then its in the drive train not the motor. If you still hear it coasting and the motor on its probably int he motor.
From what you have described ( hearing it while the motor is at idle and not revved up) it sounds like a possibility that the rod bearing is going out.You rechecked your work, and it sounds like its ok, then it has to be in the bottom end. Reguardless of milage, a bearing can go out at anytime.
Good luck and happy riding
Mike
