Timing marks on a 96' EVO
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Cruiser
Joined: Jun 2008
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From: Ethan, S.Dak.
Timing marks on a 96' EVO
Looking for a little input here please. Am installing a cam in my my 96' and have run into an odd situation. According to my manual the timing marks for the cam, idler gear, and breather should all line up to thier marks. When these marks are all aligined and you look in the timing hole, the top dead center mark is not in view. If i roll the crank to show the line for top dead center in the view hole the piston is at top but then the timing marks are not aligned. The mark for the idler gear is about a quarter turn off. Is this right or am i missing something here? My manual shows the timing marks aligned and it also shows the timing mark for top dead center but does not give reference to both. Any input would be appreiciated.
Seasoned HDF Member
Joined: Jun 2010
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From: Upstate New York
I don't think the cam alignment marks are set with the crank at TDC. There's no reference to TDC relative to the the cam timing marks in my service manual. It just says to align the cam, pinion gear and breather with their respective marks.
To tell the truth, I never paid any attention to where the crank was last time I had my gearcase open. I just aligned everything according to the book and buttoned it up. It worked fine.
To tell the truth, I never paid any attention to where the crank was last time I had my gearcase open. I just aligned everything according to the book and buttoned it up. It worked fine.
Outstanding HDF Member
Joined: Mar 2010
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From: Hallsville, Tx.
I don't think the cam alignment marks are set with the crank at TDC. There's no reference to TDC relative to the the cam timing marks in my service manual. It just says to align the cam, pinion gear and breather with their respective marks.
To tell the truth, I never paid any attention to where the crank was last time I had my gearcase open. I just aligned everything according to the book and buttoned it up. It worked fine.
To tell the truth, I never paid any attention to where the crank was last time I had my gearcase open. I just aligned everything according to the book and buttoned it up. It worked fine.
Seasoned HDF Member
Joined: Jun 2010
Posts: 9,332
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From: Upstate New York
Think about it, the pinion gear is keyed to the pinion shaft/right flywheel, so there's no way it could be assembled wrong. The cam timing marks are just set arbitrarily without regard to TDC of the flywheels, but everything will work like it's designed to.
I scribed lines in the nosecone to mark the position of the notch in the ignition sender plate, so I didn't have to retime the bike afterward. That's why I didn't look at the ignition timing marks on the flywheel.
I scribed lines in the nosecone to mark the position of the notch in the ignition sender plate, so I didn't have to retime the bike afterward. That's why I didn't look at the ignition timing marks on the flywheel.
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Cruiser
Joined: Jun 2008
Posts: 109
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From: Ethan, S.Dak.
Thanks, for the input guys. i will go by the book and line up timing marks, was courious about the TDC thing though. Guess i shouldn't try and put past automotive experince to work on a bike. Just always used TDC for timimg and thought it was thw same here. Thanks, again.
Club Member
Joined: Jun 2007
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From: North Atlanta Area, GA
One thing I learned when I installed my cam is that you shouldn't assume your bike is timed right to begin with! I too scribed those marks on the timing plate and the nosecone, and lined them up exactly when I put it back together. Ran it that way for several months. Then this week I did a static timing alignment for the Twin Tec ignition, and found that the timing was OFF about 6 degrees too advanced. Could be why Bertha's been pinging under 3000 RPM with the new cam. Gonna take the bike out to see today. After adjusting the timing, I can tell already that the throttle response off idle is much crisper than it was.
And yeah, the timing marks on the crank are just for ignition timing - to locate TDC and 35 degrees BTDC... they have nothing to do with the cam positioning. You just line up the marks on the cam, pinion, and breather gears to position the cam correctly. Pretty simple really. Good luck!
And yeah, the timing marks on the crank are just for ignition timing - to locate TDC and 35 degrees BTDC... they have nothing to do with the cam positioning. You just line up the marks on the cam, pinion, and breather gears to position the cam correctly. Pretty simple really. Good luck!
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