Changing cam chain on 103HO?

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Dec 15, 2020 | 10:35 AM

Magnut1

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Grand HDF Member

Joined: Aug 2014

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From: Toledo ohio

Changing cam chain on 103HO?

I am almost ready to do a stage 4 and my question is ... do I need to change the cam chain? I have 20K of relative easy miles on my bike. I don't beat on it like some do. no noise. Do most of you that do their own work, or had it done, change the chain along with the cams/bearings? They guy helping me said "oh yeah, change the chain or go with a gear to gear.

Dec 15, 2020 | 11:39 AM

MCSarge

Stellar HDF Member

Joined: Jul 2006

Posts: 3,029

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From: Michigan

When I do an upgrade I do it all in that area. When I did my 2007 RK with 20,000 miles on it I did the swingarm bushings and rubber mounts. I redid everything in the primary etc.. If you have it open and are going that far, don't leave anything in there that you may have to go back in and fix in a year. If your going to do a gear drive wait until you have it apart to measure the crank run out. If it is out of spec you will have wasted time and money returning the parts to go back to a chain. Some people don't like the whine off a gear drive also, so that may be a consideration.

Dec 15, 2020 | 04:30 PM

hattitude

Seasoned HDF Member

Joined: Sep 2008

Posts: 14,156

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From: San Diego, CA

Quote:

Originally Posted by Magnut1

IMHO.... No...

You have the roller chains between your cams and gears... Many people have gone over 100k miles on OEM roller cam chains.. At only 20K miles, if there are no signs of abnormal wear, keep the chains and the OEM tensioners...

Unfortunately the 2014 bikes have an HD allowable 0.012" of runout, which is both absurd and can cause uneven, accelerated wear issues... but if all looks good... reuse them, I have on two bikes..

If you want to go gear drive, nothing wrong with that, but it will be expensive compared to keeping the chain driven cams.. Also you will need to verify your bike has less than .003" of runout or the gear drive cams will self destruct...

I have two bikes with gear drive cams... one high performance engine, and the other because the bike had very low run out, and I had never used them before... Both bikes have no noticeable noise from the gear drives... You have to listen very carefully, up close, to tell any difference...

There are always exceptions to every rule, but I believe that most gear drive systems with loud gear noise/whining are because;

1) They either didn't measure runout, or are over the .003" runout required for gear drive cams.

2) They didn't follow the install directions completely, and failed to check/correct the backlash between the rear cam outer drive gear and the crankshaft pinion gear.

From the S&S gear drive install instructions:
"Too much backlash can cause excessive gear noise or clicking caused by the reversing of the forces applied by the lifters to the cam lobes. Insufficient backlash, will cause gears to whine, wear prematurely, create excess heat, and may cause breaking of the gear teeth and engine failure"

Dec 15, 2020 | 06:15 PM

KumaRide

Grand HDF Member

Joined: May 2008

Posts: 4,624

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From: Newcastle, Ca.

Installed cams on 2 bikes both with ~20k miles and reused chains. Big bore kits with heads, cams, cylinders... dont come with chains and I never say anyone list chains when sharing their build parts list.

Whats your build?