I do'nt know how it works fella's, I'm just saying my 08 Road Glide has no tran. noise, none. This ain't my first HD but it is the smoothest shifting one I have ever ridden. I am not bothered by the heat to much, maybe just me, maybe I got lucky but with only 500 miles it is the best so far. Well gota go ride.

 

cderider, on my 07 i've got the slight whine in 5th, it's actually gotten much better. Having said that, no clatter that I can hear as long as I don't lug the engine in 5th or 6th, But as far as shifting goes? never had a problem. Real smooth and positive. Tho first, has that distintive clunk when you engage it.

 

If the Isolation Drive System is the Cush Drive that they are using the vrods, it is a compensator bowl with a rubber gear type fitting. It wouldn't do anything to stop the 5th gear whine that I can see. I am going to see if I can test drive a 2008 and see for myself.

 

Everything being equal it will probably quieten the whine a measureable amount. Measureable to the human ear? Maybe, maybe not. One thing it definitely should do is take some bite out of the clatter when running too low in the RPM range for the situation. It will soften each and every blow to everything between the wrist pin and the rear tire contact patch. It will give itself up in time doing that, but it's got to be cheaper to replace than just about anything else in the flow of power.

 

Ok, so not know enough about the IDS, what is the true purpose of the IDS to dampen the harmonics? Are there retro kits out there for the older bikes? I still can't believe this addresses the quote with the tranny noise! Any thoughts on this matter?

 

The purpose is to spread out each firing impulse over a greater length of time. The same amount of energy ends up ultimately getting delivered (well, 99.9% of it anyway; certainly the rubber bushings will heat up a little and that only happens when energy is being dissipated) but it "ramps up" much more gradually and eases off some instead of falling instantly like off a cliff.

Okay, think of it this way. Say you've got laminate flooring in your kitchen and dining room but there's a 1" divider strip sticking up 3/16" in the archway between the rooms. You're on the floor in one room and your son is on the floor in the other. You're rolling a toy car back and forth to each other. When the car gets to the divider strip it hits hard with some noise, catches some air, then lands again (with more noise) and keeps going. Think of that as the direct connection between the sprocket and wheel hub.

Now you take a piece of poster board 12" long and form a more gentle ramp over the divider. When the car hits that it smoothly goes up and over. Think of that as the IDS.

Now visualize doing the same with a little car with a trailer, or maybe a train with a few cars would be a better picture. Think of the differences in the way it would traverse the divider strip, both directly and with the ramp. With the IDS, at each chain-to-sprocket and gear-to-gear juncture in the driveline the interaction will be much smoother without the sharper increase and decrease in energy of every transmitted power pulse.

What's more, with straight-cut gearsets and chain/sprocket interfaces the effect would be akin to the car hitting the divider straight on. With the helical-cut gears of 2,3,4, and 6, the two transmission shafts will be thrusting opposite each other sideways. Think of that as the car (or better, train) hitting the divider at an angle and what would happen between the sharp or soft versions. Well, maybe that's reaching just a bit, but the shafts will hammer their thrust bearing surfaces much more smoothly with more "rounded" impulses. That will in turn reduce clatter even more than those types of gearsets do anyway.

 

I like to consider myself mechanicly inclined! From the last post I understand what the IDS is doing. What I don't understand is how this IDS is masking the noise issue with some trannies! I do understand harmonics just can't believe this is the solution. Still curios to see the breakdown on the 08 vs the 07 tranny!! I still believe that "Red Line Heavy Shock Proof" is a great and really make a HUGE difference....

 

Rode a 08 ultra yesterday, it still had a faint whine in 5th gear, didnt notice any other noises couldn't tell any difference with IDS over mine without. No ping, still hot like 07s. Did feel like a slight lag when getting on throttle with new cableless system. Did see in newest edition of catalog, I got one at dealer that is different in SE section from 08 catalog I got in mail. In this one it gives part number for the 08 SE air cleaner, it is different from the one for 07 says 08s have 50mm throttle body. Shop foreman said he is getteing downloads already from harley, and air cleaners are coming in soon. Looks like harley will be ready to retune the 08s very shortly.

 

That's how it masks (as much as it will) the noise. It will soften each and every blow the gear teeth make against each other. It will soften each and every blow the main and counter shafts make against their thrust bearings. More of a gentle push instead of a hard slap will reduce stresses on the components and they will make less noise doing what they do. Much the same as the car traversing the gentle ramp quiets things down and makes them less "eventful" vs. hitting the harder-edged divider strip.

You know, the drive belt already does a bit of this anyway. And I don't think harmonics plays much of a part in the scheme unless it's in a detrimental way. I could easily see a situation where the inclusion of the IDS could, at certain frequencies, cause the gears to want to spring in the opposite direction thus meeting the next power pulse with more force than it would at that same frequency without the IDS (though the gears would be in a relatively unloaded state at that moment). Of course the energy would be re-absorbed as the force compressed the rubber bushings so the end result might not be damaging to the goods. But in such a situation it's conceivable there'd be a little more noise. These bands of critical harmonics would have to be tuned out of the system as best as possible. I'm sure there are some smart engineers at the Moco and that their hands are not completely tied in matters such as these.

I don't consider it so much a solution to the tranny "noise problem" as a means to decrease wear and tear on the components to increase their reliability and longevity. I firmly believe there must be a few unfortunate individuals with problematic units but their being ultra-vocal about it masks the extremely small percentage they actually represent. Part of it is most certainly that they're just malcontents.

Anyway, just think of how quiet things will be with a combination of the good lubricant and the IDS!

 

Gunrunner

I would assume that you know the rattle or tranny noise everyone is talking about with the 07's. From your ride on the 08, do you believe that the IDS is the fix? I understand you stated there was still a slight noise, but what are your thoughts? Did they change something in the 08's??

Bob