Interstate ICM on a Standard

[Farther]

I know someone has done this.  Please report your experience.

[SANDMAN5]

Yeah it's been done lots of times. I'm going to do it
myself when I get enough coinage to buy one.

[dago mooserider]

I've been considering this mod as well on my 98 std. I'd love some more low to mid grunt but am not willing to sacrifice the high end. Anyone know if the Interstate ICM mirrors the standard in the higher rpms? 7000+ rpm shifts is how I eat the harleys....

[John U.]

I'm running an I/S ICM on my Standard. It's a plug and play mod. The I/S ICM is 2 degrees advanced and has a steeper advance curve to about 3500rpm. After 3500 I don't think there is a difference. These bikes don't need more high rpm advance.
Anyway, you'll notice the difference. Install a set of I/S carb springs
while you're at it. They are cheap (HDL has them for about 12 bucks), they give a quicker throttle response that plays well with a steeper advance curve.

[Jack B]

I also I have one in my 98 Tourer and I agree with John U but I do have a buzz at about 1500 rpm's that I didn't have before no big deal. Gas mileage is a hair better. 

[tank_post142]

my standard cuts out the rpms at 6700

[dago mooserider]

Hmm. I think mine is more like 7200. Could be just the tachs being inaccurate. Not a whole lotta power after 6500 anyway but it sure sounds sweet.

[TearlessTom]

Funny,
Mine feels much stronger above 3000, and really starts to shine about 3500 rpms, acceleration is much stronger and smoother throughout the entire range. And although I run it harder I am getting better mpg and don't hit the rev limiter even though the tach reads 7000+. I've also done the interstate springs mod and the electronic timing advance mod. I guess with these having already been done it really runs great.

http://cgi.ebay.com/ebaymotors/Honda-Valkyrie-GL1500-IGNITER-CDI-IGNITION-MODULE-/190437533757?pt=Motorcycles_Parts_Accessories&hash=item2c56f6283d

[John U.]

I thought I remembered a detailed explanation of the ICM question.
The following is a post by Airetime from a couple of years ago:



In regards to the IS ICM unit, you will be advancing it by programming 2 degrees advance through the 1800 – 4500 RPM range only. You don't lose your top end. A timing wheel that has a 6-degree advance has that advance from start to finish or from 900 RPMs to red line. Because they have a fixed advance all the way through, but they lose top end. By adding another 4 degrees through modifying the timing wheel, you will benefit by not only the I/S ICM programming, but also the fixed additional 4-degree advance. You will have the 4 degree advance in the lower RPMS 900 - 1800 RPMS, full 6 degree advance in the 1800 - 4500 Mid range RPMS and back to a 4 degree above 4500 RPMS. Because the mod of only using an advance of a fixed 6-degree is all the way through, those will run rougher, usually demand high octane and reduce the top end more than you. I ran my Tourer with a fixed 4-degree advance before I got the I/S ICM and I noticed that it ran a little rougher and I had to run the high-test fuel. Once I added the I/S ICM unit it smoothed it out and gave me the low end, mid range and top end that I wanted. You will have an advantage if you combine the both.

I suggest that you also order the Carb-springs while you are at it as they will increase the throttle response and costs only about $13 or $14. If you run a Standard/Tourer with the I/S Carb Springs and a I/S ICM it runs like a stock I/S but doesn't have the extra 100 pounds that it was programmed to carry. Now because it thinks that it is now a stock I/S, it runs like one only faster because it doesn't have the extra weight. Take a look at doing the ECT Mod (in ShopTalk) for even more wallop!

Remember if you install just the IS ICM unit, you are advancing it by programming 2 degrees advance through that 1,800 – 4,500 RPM range only. You don't lose your top end and the mileage should increase by giving it a better mid range performance, depending on how much fun you are having.

[dago mooserider]

Sweet. This is perfect for me as I may be pluming a nitrous system in the future. So a trigger wheel is a no-no. Too much timing and too much nitrous equals big time detonation. New interstate icms are not cheap however..... too bad about the dyna being d/c, but I heard lots of reliability issues anyway.

[Ramjet]

03 Standard; bought IS  ICM two years ago off of Ebay and carb springs from HDL.  I like the increased power mid-range.