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Who? Me?
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Discussion Starter · #1 ·
Ive yanked my cams out of my new build due to some noise that I wasnt comfortable with. After pulling the rockers and push rods I wiggled the cam gear against the pinion gear somewhat and my gut feeling is that is too much. I went on to yank the cam plate and check the inner gears and I cannot detect any lash between the gears. Im wondering if they are too tight. How do I tell? They seem to spin okay, but Im not real sure. I know My brother-in-law has a dial indicator that he may let me borrow if I ask real nice, but even with the dial, Im not sure Im competent enough to get an accurate measurement. Any suggestions?
 

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XLIII
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Find someone who is and have them help.
Good instructions on Wood's site. Harley Hawg has some good pics as well.
 

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This page:
http://www.harleyhog.co.uk/1550/bb14online.htm
shows one way of checking the outer gear lash. I think I saw some instructions somewhere (Wood's maybe?) that says to check the inner gear lash using the same setup while holding the front cam thru one of the lifter bores. You would do this BEFORE installing the crank pinion gear. The thing I am thinking about checking the inner gear lash this way is you will be measuring off of a larger diameter (outer) gear. So, your dial indicator reading would be (maybe) a few thou more than the actual clearance in the inner gear set.
On page 4 of that series in the link above, He measures the inner gear lash with the cams in the plate on the bench. Without the rear of the cams in their bearings, I think the measurment could be different than when they would be installed.
 

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Great timing on this thread. I'm starting my assembly tomorrow and just picked up my dial indicator on the way home tonight. Thanks Pa-Glazier for the link to woods. :wavey:
 

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Those gears may make noise even if theyre setup correctly. Unless its whine heavily, I dont think you need to worry about it.
 

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Amer_ninja said:
This page:
http://www.harleyhog.co.uk/1550/bb14online.htm
shows one way of checking the outer gear lash. I think I saw some instructions somewhere (Wood's maybe?) that says to check the inner gear lash using the same setup while holding the front cam thru one of the lifter bores. You would do this BEFORE installing the crank pinion gear. The thing I am thinking about checking the inner gear lash this way is you will be measuring off of a larger diameter (outer) gear. So, your dial indicator reading would be (maybe) a few thou more than the actual clearance in the inner gear set.
On page 4 of that series in the link above, He measures the inner gear lash with the cams in the plate on the bench. Without the rear of the cams in their bearings, I think the measurment could be different than when they would be installed.
I think the Woods method is more accurate. I tried it both ways and got different readings. It just seems to make more sense to do it with the cams installed minus the pinion gear.

Rick
 

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XLIII
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atengnr said:
Those gears may make noise even if theyre setup correctly. Unless its whine heavily, I dont think you need to worry about it.
Gee, mine don't.
Should I tear 'em down and see what's wrong?
 

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atengnr said:
Those gears may make noise even if theyre setup correctly. Unless its whine heavily, I dont think you need to worry about it.
If set up correctly they likely will not make noise. My motor is quieter since I did the 98" with 37G cams than it was stock.

Rick
 

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BFFB
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HarleyHeevo said:
Ive yanked my cams out of my new build due to some noise that I wasnt comfortable with. After pulling the rockers and push rods I wiggled the cam gear against the pinion gear somewhat and my gut feeling is that is too much. I went on to yank the cam plate and check the inner gears and I cannot detect any lash between the gears. Im wondering if they are too tight. How do I tell? They seem to spin okay, but Im not real sure. I know My brother-in-law has a dial indicator that he may let me borrow if I ask real nice, but even with the dial, Im not sure Im competent enough to get an accurate measurement. Any suggestions?
you can also try checking inner gears with a pair of needle nose vise grips with black tape to cushion against the cam ,,,grab front cam with pinion gear off , not much room to grab and it will be slippery ,,clamp with vise grips and rest it on solid surface so it wont move ,this holds the front cam and allows the lash between cams to move back and forth ,, then check with dial indicator on cam drive gear,,then rotate 90 degrees and repeat
 

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BFFB
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Amer_ninja said:
This page:
http://www.harleyhog.co.uk/1550/bb14online.htm
shows one way of checking the outer gear lash. I think I saw some instructions somewhere (Wood's maybe?) that says to check the inner gear lash using the same setup while holding the front cam thru one of the lifter bores. You would do this BEFORE installing the crank pinion gear. The thing I am thinking about checking the inner gear lash this way is you will be measuring off of a larger diameter (outer) gear. So, your dial indicator reading would be (maybe) a few thou more than the actual clearance in the inner gear set.
On page 4 of that series in the link above, He measures the inner gear lash with the cams in the plate on the bench. Without the rear of the cams in their bearings, I think the measurment could be different than when they would be installed.
i had your same concerns , i think the front of the cams need to be held firmly in the cam plate for an accurate reading , the lash measured from the id of the cam drive gear is the same as measured from od , the reading doesnt change as the radius gets larger
 

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woodwalkertc88 said:
i had your same concerns , i think the front of the cams need to be held firmly in the cam plate for an accurate reading , the lash measured from the id of the cam drive gear is the same as measured from od , the reading doesnt change as the radius gets larger
:hmmm:
Oh? I know I have CYS (Can't Remember Stuff), but I vaguely remember that the circumference of a circle equals its diameter times PI, and there are 360 degrees in a circle. Lets say the (pitch) diameter of the inner gear is 1 inch. Then the linear distance (like pulling thread off a spool) you would get for each degree of rotation would be 1*PI/360 inches or about 0.0087 inch. If you had 0.001 in lash, that would allow the one inch diameter gear to turn (0.001/0.0087 or about) 0.115 degrees. Now, we have two different diameter gears mounted on the same shaft so they have to turn the same amount of degrees rotation, right? For grins and giggles, lets set the outer gear diameter at 2 inches. Working the math back through[(2*PI/360)*.115], I would expect to see a dial indicator reading of around 0.002 inch.
In short, If you use the measuring setup as shown in the above links, I think the dial indicator reading should be divided by the ratio of the diameters (outer/inner) of the gears to get the correct lash. -2$en#e-
.
 

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Who? Me?
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Discussion Starter · #13 ·
I think Ive decided to box up the gears and cam plate and send them to HDWRENCH and have him take a look at the inner gears. Im guessing he has been pretty busy, as Im having a tough time getting a hold of him and havent seen him on the forum lately. Ill let you know what I find out. Thanks for all the help.
 

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OBSESSED
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I don't believe sending them back to Steve will do you any good because checking the lash on the inside gears is to measure your crank run-out and needs to be done installed on your bike!

Dave
 

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BFFB
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Amer_ninja said:
:hmmm:
Oh? I know I have CYS (Can't Remember Stuff), but I vaguely remember that the circumference of a circle equals its diameter times PI, and there are 360 degrees in a circle. Lets say the (pitch) diameter of the inner gear is 1 inch. Then the linear distance (like pulling thread off a spool) you would get for each degree of rotation would be 1*PI/360 inches or about 0.0087 inch. If you had 0.001 in lash, that would allow the one inch diameter gear to turn (0.001/0.0087 or about) 0.115 degrees. Now, we have two different diameter gears mounted on the same shaft so they have to turn the same amount of degrees rotation, right? For grins and giggles, lets set the outer gear diameter at 2 inches. Working the math back through[(2*PI/360)*.115], I would expect to see a dial indicator reading of around 0.002 inch.
In short, If you use the measuring setup as shown in the above links, I think the dial indicator reading should be divided by the ratio of the diameters (outer/inner) of the gears to get the correct lash. -2$en#e-
.
i worded my 1st post wrong , let me run this one by you
i thought so too , and i talked to a machinist and and he tried to explain it to me ,,, and was assured it worked and it did ,, i had a standard and 1 over sized inner gear installed on my bike , the 1 over worked and measured a different gear lash on the inner gears at the cam drive gear ,,,
since the gears are machined to match and designed to run on the same cam shaft ,, and the indicator is set up to measure the travel at the tip of a tooth before binding .... if you added or subracted a tooth in your scenario on the larger gear wouldnt the reading on the dial indicator change ? in other words if you crowd another tooth on the larger gear wouldnt it read less ?
i also meant i think the rear of the cams need to be held in thier bearings ,in other words with the cam plate installed to check inner gears
 

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IronButt
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I am here, yes I have been busy, BEST thing is too call me. I can be reached at either number. Heevo give me a call we can get you sorted out.
 
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