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Top dead center?

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I am trying to remove my cams so I can do my bbk install but I can't seem to get proper tdc. So my lobes are at 10 and 2 but I can't make that happen when the engine shows tdc through the window. When the engine shows tdc the lobes are pressing on the valves. I am taking my bike apart to put in the bbk and the bike has been running great. What's going on? What do I do now?

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Turn it untill you see the line in the hole with the t next to it, take a picture of both cams and hole and show us. The cams might not be perfectly on 10 and 2 but thats ok as long as they are not compressing the cams

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If you're pulling the cams and top end it makes no difference if you are at TDC..

Rotate motor till the cam lobes are off the ramps and near the base circle, remove the cam chain tensioner, and then the cams.

 

Have you looked at the BB kit install paper in the FAQ? 

DRZ Big Bore Install
Started by E.Marquez12 Feb 2011 07:54 AM
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Yes, erics write up is what I am going off of.

As long as they don't need to be at engine tdc then I will pull them.

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Yes, erics write up is what I am going off of.

As long as they don't need to be at engine tdc then I will pull them.

Thats good I hear that eric dude knows this platform :lol: 

 

No they do not NEED to be at TDC..

 

 But if you can not figure out TDC now..... how are you going to when you need to after the BB kit install?

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As mentioned it doesn't matter to tear it apart. However, are you sure you are on the right stroke? Did you try rotating it over again?

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Thats good I hear that eric dude knows this platform :lol:

No they do not NEED to be at TDC..

But if you can not figure out TDC now..... how are you going to when you need to after the BB kit install?

Eric that's my point. There is something here about timing that I don't understand

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Eric that's my point. There is something here about timing that I don't understand

So do this

Rotate forward the motor until the index line in the sight window centers.

Take a PIc of the cams and sprockets for straight from the side

Rotate again

Till the index line comes up again

Same with the pictures

Let's see where that gets you

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Eric that's my point. There is something here about timing that I don't understand

 

You do understand the crank turns twice for one rotation of the cams? So you will pass the TDC mark twice before the cams make one revolution. So TDC will only be "TDC" every other rotation?

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Okay I think I got it. Got it to line up and lobes not depressing the valves. Thanks guys.

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And check you top dead center marks by putting a skinny screw driver down the plug hole and make sure your marks line up when the screwdriver is at it's highest point.

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Pictures, directions via internet can be confusing.. 

just remember small valve pockets on this motor towards exhaust

Large valve pockets toward the carbs..

 

Your TDC issues still are a concern unless you have positively figured that out.  

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