bluehdmc - 3/5/2012 12:22 AM
I wrote to Andrews cams and asked what they would recommend for my 2004 FLHTCUI (the one with sidecar) with stock displacement 88", air cleaner change and screaming eagle exhaust, (which isn't as loud as the same part # exhaust on my 99 Road King w/o sidecar). They got back to me and recommended their "21" grind, the cam can be used with stock springs so you don't even have to remove the valve covers. The next time I take it apart for chain tensioner replacement, I'll probably go with that and a gear drive.
,
===================================================================
To do a cam change without removing the valve covers on a Harley Twin Cam, you will need to use your bolt cutters on the existing pushrods. Then you will have to spend another $135 or so to get a set of adjustables, Harley or otherwise. The dfference between removing the valve covers or changing pushrods is mainly time since the gaskets are very expensive.
Gear-driven cams are problematical on a Twin cam. The flywheel/crank assemblies need to have a very low T.I.R. (total indicated runout). Most mechanics will want to use a dial test indicator on the tming side of the crank assembly when contemplating such a change. If the T.I.R. is greater than about .004, the ensuing noiise with a gear driven setup will very likely be objectionable. It will also result in excess wear on the timing and cam gears. While HD now uses a T.I.R. maximum of .010 (from my 2011 Service Manual) that would be far too much to even think about running a gear driven cam setup.
In fact, gear-driven cams have become passe' since the introduction of the 2006 Dyna Twin Cam and 2007 and later Twin Cam engines. Those engines, besides having 96 cu. in. (most years, early 2006 Dynas were 88" and many HD's now are 103") had a much improved cam plate similar to the 2000 and later Softail plate. This has hydraulic tensioners and will reduce the necessity of tensioner wear to a much greater extens, although it pays to check them on a regular basis, say every 25,000 miles.
Harley developed a hybrid cam plate to retrofit standard pre-2006 Dynas and FL's. This has the hydraulic function on the cam chains. Later bikes all have this change.
The 21 cam would be OK for a sidecar as it is the mildest cam of the entire S&S line, one notch above stock. They cost the same as the more radical grinds. though. LOL.
When you are talking about changing things on Harley-Davidsons, there is no free lunch. 🙂
