Hi
Just received my EV27 to fit to my 1986 FLST and was reading the fitting instructions on the Andrews web-site. www.andrewsproducts.com/PDF_files/CamEV80.pdf

One question.
They say:
"To make sure that your new camshaft drive gear will operate quietly, the cam gear to pinion backlash must be correctly set up. Proper backlash is .0000/.0005 for a cold engine. Andrews Products recommends that BOTH the new gear and the original gear be measured as described on the last page of these instructions. If both gears measure within .0005" of the same size, it should NOT be necessary to change gears. If a different size gear is required, Andrews Products has them. Excess backlash will cause gear noise which sounds like loose lifters but will not hurt anything. Insufficient backlash will cause a distinct gear whine and should be corrected since gear tooth damage will result over a short time period."

This I understand.
To measure they say to use .108" pins in opposite teeth and measure both gears. Surely if I measure both old and new cam gear with any size pins, or just from top to bottom tooth and the measurement is within the recommended tolerences, the new gear will be ok?

Am I correct in this assumption, or am I missing something?

Thanks,

Tony.

 

The .108' measuring pins are designed to sit in between the teeth at the proper level, to take into account the way the cam gear and pinion gear teeth need to mate properly, since the teeth are machined with a taper. Also, the teeth wear over time.

Use the .108" measuring pins for an accurate measurement. That's what they're for!

 

if you were to use a smaller dia. pin, they would effectively fit further into the "v" of the gear, giving a smaller measurement. likewise a larger dia. pin would fit farther out in the "v", giving a larger measurement. you have to use the same pins as they use to get an accurate measure.

 

where do you get the .108 measuring pins?

 

Go here-

http://www.georges-garage.com/evo_engine.htm

Bob
97 Heritage

 

I used the pins and measured with a digital caliper. You really need to use a micrometer. When I checked mine it looked very close (with the caliper). I installed the cam but found that I had the high pitched whine that indicated a "too tight" gear fit. I ended up pulling the cam and switching to the stock cam gear. I would recommend just using the stock cam gear to save extra work and aggravation.

 

thanks 'piperbob'.... i get all my tools from George's ....wonder why i hadn't noticed them, before

also, can you get just the cam gear from the dealership instead of using one that came out of a beast with 30k on it?

 

You CAN get that gear from the dealer. If you know what size yours is they'll sell you one, I'm not sure it'd be worth doing if all you do is measure your gear to determine the size and then order a replacement...

Inspect the one you have and if it's perfect with no chips or wear patterns on the teeth, it should be good for many more trouble free miles. Assuming regular oil changes and it fit right in the first place there just isn't much to go wrong there...

 

makes sense, woodnbow.... i tore apart the top end to replace pistons, headwork, and honing... oil was in bad shape.... a lot of moisture had gotten into this thing so i'm just anticipating what's below might not be in such great shape...we'll see, though

 

Well you're right to inspect everything closely in any case... Nice work for a winter day!