How to mesure crank run out?

[Ryanlilly]

I have a 02 700 edge and I need too mesure my crank run out. How do I do this/ what tools do I need? Thanks guys!

 

[tdblakes]

Kraven knows.

 

[Kraven]

CRANK RUN-OUT

I have a 02 700 edge and I need too mesure my crank run out. How do I do this/ what tools do I need? Thanks guys!

Set up the dial indicator approx 1/2" in from the end of the crank.

Remove the spark plugs and rotate the engine over by hand.

.002" to .0025" is the ABSOLUTE MOST I would want to see for crank run-out!

The 700 has a couple of threaded holes in the front of the case that you can use a scrap piece of metal to bolt to and mount the dial indicator on.

IF your crank checks out to be within spec, do yourself a favor and send the primary clutch out to be balanced. It will extend crank life and be noticeably smoother

 

[Ryanlilly]

Set up the dial indicator approx 1/2" in from the end of the crank.

Remove the spark plugs and rotate the engine over by hand.

.002" to .0025" is the ABSOLUTE MOST I would want to see for crank run-out!

The 700 has a couple of threaded holes in the front of the case that you can use a scrap piece of metal to bolt to and mount the dial indicator on.

IF your crank checks out to be within spec, do yourself a favor and send the primary clutch out to be balanced. It will extend crank life and be noticeably smoother

Thank you! Clutch was already sent out and balanced.

 

[94fordguy]

Would something like this be precise enough or is there another supplier someone could recommend?


Thanks

http://www.harborfreight.com/clamping-dial-indicator-93051.html

 

[Kraven]

DIAL INDICATOR

Would something like this be precise enough or is there another supplier someone could recommend?


Thanks

http://www.harborfreight.com/clamping-dial-indicator-93051.html

That will get the job done.

I know it's a "cheapo" coming from Harbor, but it still has to be reasonably accurate.

I don't have my EDGE 800 anymore, otherwise I would post a pic of the homemade mounting bracket I fabbed for mounting the dial indicator.

I utilized the spark plug hole adapter that holds the dial indicator.

Then I tapped (with 14mm) the 2" aluminum angle and screwed the adapter into that.

 

[High Velocity]

Kraven, I also make homemade brackets for whatever brand of sled I'm dealing with. I make mine out of steel though and use my mag base for my dial indicator. Either way is plenty accurate as long as the bracket is solid.

 

[Jay]

I use a piece of steel flat stock, clamp it onto the aluminum guard between the clutches that covers your speedo drive with a pair of visegrips and set the magnetic base on that. I just bought a BB800 on saturday for cheap, checked the runout, it is 0.0085 DOH

 

[JMCX]

I use a piece of steel flat stock, clamp it onto the aluminum guard between the clutches that covers your speedo drive with a pair of visegrips and set the magnetic base on that. I just bought a BB800 on saturday for cheap, checked the runout, it is 0.0085 DOH

It sounds like you are attaching to the chassis. This usually won't work because of rubber motor mounts throwing off the reading.

 

[High Velocity]

It sounds like you are attaching to the chassis. This usually won't work because of rubber motor mounts throwing off the reading.

I agree. Dial indicator needs to be on the engine. Eliminate all possible chances for error.

 

[4Z]

I pulled the flywheel off so the magnets didn't f-with me and used the magnetic base style of anchor. And bolted a chunk of steel to the motor, and yes, this was not a Poo...

Ryan, if you want to borrow my nice dial indicator and my cheap Chinese mag base set up, lemme know....

 

[Ryanlilly]

Thanks guys!

Lynn you have a PM

 

[milehighassassin]

I have heard that crank runout can be off after doing major jumps or drops...
It will be off initially and then later be alright.

Anyone know the truth to that?

 

[Kraven]

I have heard that crank runout can be off after doing major jumps or drops...
It will be off initially and then later be alright.

Anyone know the truth to that?

Yeah, I read that in one of Indy Dan's posts..........................................

??????????????????

So by applying Indy Dan's theory, all the POLARIS 800's with major run-out can be fixed by doing jumps and landing at the precise moment will "straighten " them out again.

No need for new cranks!

Great!

Hmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm

 

[Jay]

I find using the method I described to be pretty accurate, I actually had 8 thou in the chassie and when I pulled the engine and checked it on the bench using solid mounts I saw 8 1/2.