View Full Version : camshaft installation timing

10-21-2004, 05:43 AM
Is it possible to install a evo camshaft 180 degrees out?

10-21-2004, 06:04 AM
anything is possible- but the timing marks are fairly clear....

how about letting us know what's happneing...no start after a cam change maybe?


10-21-2004, 12:39 PM
Is it possible to install a evo camshaft 180 degrees out?

Would not be a good thing. :mellow:

10-21-2004, 04:57 PM
Thanks Junior for your quick response. The crank turns two revolutions for one cam revolution. As you said lining up the marks is easy and I have done that. My question is when I rotate the crank only once the marks do not line up. Is this the position where they should line up or does it matter? It seems to me with a 2 : 1 ratio that there are two ways to go here. When I rotate the crank twice it all lines back up like any other 4 stroke. I hope I,m not giving you a headache over this. Thanks for all you do. :huh:

10-21-2004, 05:47 PM
That sounds right Hangon

When the you rotate the crank once you go through intake, compression cycles then the next rotation power & exhaust.

10-21-2004, 06:09 PM
thankyou wide, My concern here is having the exhaust valve open and intake closed on intake - comp stroke.This is why I ask If it matters if the cam is 180 degrees out because there are two ways it can be installed in relation to the positioning of each piston in its respective cylinder. Thanks :unsure:

10-21-2004, 07:58 PM
wide's gotcha- but you also kinda answered your own question....

since the cam turns at half the crank speed the cam would alternate between "mark" and "mark+180 degrees" for each full crank revolution...


10-22-2004, 12:53 AM
:unsure: Is there a #1 top dead center for a place to start..

10-22-2004, 01:07 AM
on an evo/alt. shovel- there's only one way possible if you watch the marks...

the crank mark will be striaght up
the cam has two marks- align the first at 6-oclock to match the crank, then the other will be at 8-oclock to match the breather.


10-22-2004, 04:49 AM
hi hangon
food for thought important for cam change......

my first question is is this the same cam you removed or is this a different cam??

If it is a different cam there is a couple of things you need to ck out for proper instilation that has not been brought up.

cam lash: this is the mechshing of the gears . all gears are cut to farily exacting spects. there might be some differences in tollerance which could produce in a binding of the gears causing excessive wear on the cone bushing and seal. this info. can be found ia the HD manual for the YR m/c you own . The less a lash will produce a ticking sound that personally drives me crazy. This is all deterimed by chosing the correct pinion gear for your set up as described in the tech manual. There are special tools for this or you cam do it the old fashon way by feel.

second is end play!

real important: cam end play is more important to me than lash. this requires the correct shimming of the gear. with electronic timing this is more liberal. end play should be about 25 thou. I usually set mine up at 10 thou. changing cams the end play needs to be checked. some cams are longer than others just by a little bit and can bind against the cam cover bushing and the engine case. causing major problems. This is not rocket sience once you have seen it done it's not a big deal. but if this is your first cam instalation seak some local experiance for some one on one. I love tearing um a part an putting back!!!!!!!!!!!!!!!!!!

good luclk

10-22-2004, 04:52 PM
:D Hello fellas, Thankyou all so much for your knowledge & support. Seems I have this bad habit of trying to complicate simple shit coupled with a lil paranoia about fuckin up. I really hate to do things twice unless she is really fine. I just picked up the cylinders at the machine shop & will be back together this weekend. Thanks for your support!

10-22-2004, 08:05 PM
hangon, curley has some very good pointers for you there , another thing i have done is to reuse the gear from my old cam so that i get a good match no wine or clicking also when cheaking end play make sure you have the gasket fitted on to the nose cone it will make a differnce , i tend to want mine a little on the lose side , but to each there own

10-23-2004, 04:31 AM


I just bet there new pistons involved in this???
One thing thats hard on a motor is a new top end on a marginel bottom end.... not that yours is:

Here is a couple of things to look at:

First: take your new piston pins and slide them into the rods and see if you feel any excessive play. if you can move them around as if tipping them side to side and there is movement you may need to replace your rod bearings for the piston pin. with new top end exriting more force on a worn beraring this will show up shortly as Knock!!!


Check your rods at the crank pin;

Take each rod in its highest possiton and lowest positon by rotating the motor in its normal rotation.

at the high and low point lightly hold the rods with your finger tips and pull up and push down this requires no force just feel if they move. If you think you have play envolved take the rod or rods in question and move them to the highest point of their rotation. at this time lightly pull up ward on the rod and give the rod a good smack with the palm of your hand . if the rod makes a clunk you may need to have your rods rebuilt. I know this extra work but if the are worn and with a new top end you will find out sooner than later. Just some thing to think about

good luck
curley B)

10-23-2004, 05:01 AM
I know you mentiond you were nervious about what you are dooing. It's normal just go step by step with your plan of attack. Dont rush reaserch answers as needed. If in doubt log on and find out. I know if this old knotthead can do it so can you. I know everyone here will help you along the way. this experiance of working on your m/c is something rare these days and thats the way it should be done today with friends helping friends next thing you know you will be sharing with others passing the BIGGG secrets LOL :lol: :lol: :lol: :lol: B) curley

10-23-2004, 07:58 AM
Thanks a million Curley for your great advice on checking the lower end. This motor only had 19,000 on it but it only took a few minutes to check it out with the methods you outlined. I then went ahead and gapped the rings,placed them on the 10 : 1 pistons and installed them in the cylinders . Trans. in gear with rear wheel locked I slid the cylinder & piston as one into the rear. I had allready installed a wrist pin keeper on one side of each piston on the bench. I made a tapered wooden dowel to pull through to line up the piston & rod and chased it with the wrist pin, installed the clip & that was that. Heads & Rockers tomorrow. I used .109 rods to measure the cam gear & was lucky enough to not have to change it. It has been a good while since I built a Harley motor & I really appreciate the positive affirmations & comaradarie of all of nice folks on this site. I have alot more confidence today and in a few days it will be time to.............................HANGON :D