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I break stuff.
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Discussion Starter #1
:danceGood news! The awful racket in my motor was actually the compensator sprocket loosening up. Yaaay! (Yes, I guess I'm officially a Drama Queen now, for being so paranoid). What a HUGE relief.

Now, we're going to have some fun. They put the beastlet on the dyno and the numbers are even WORSE than they were before (Thanks for NOTHING, Chicago H-D!:mad:). 70/87, when it should be more in the vicinity of 100/100. Brian will be back in the shop next week and I can't wait to hear what his recommendations will be. In the meantime, I've got to dig out the SERT and get it over to the shop.

These boys are a very, VERY bad influence...
 

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Well, it is good news about the sprocket!
More $$$ to be spent in other ways.....UhOh...it is that bad influence that you speak of seeping into my consciousness. :)
 

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STAND AND FIGHT!
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13,503 Posts
What mods have been done to your bike that you would expect 100/100?
 

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On a ride
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Outstanding news KBO!

As Nathan notes/asks... the 100/100 club is an exclusive gathering, a membership requiring serious work. Don't let the attainment of it come at the expense of reliability.
 

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I break stuff.
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Discussion Starter #6
It's a 95" motor, heads have been ported/polished, she's got oversize exhaust valves, Stage II Race download, true dual SE exhaust, 211 cams (which may be the problem)... lots of goodies but never quite "finished".

When the ex first put her together, it was with an eye balanced between reliability and kick.

You'd never suspect a thing if you were to look at her, which is what I love the most.
 

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Touch my monkey....
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It's a 95" motor, heads have been ported/polished, she's got oversize exhaust valves, Stage II Race download, true dual SE exhaust, 211 cams (which may be the problem)... lots of goodies but never quite "finished".

You'd never suspect a thing if you were to look at her, which is what I love the most.
That kind of work should put you close to the 100/100 club. Not sure why you're not there. Even if slightly off, I could see 90/75.... I have a friend doing the same gig right now.;)

This guy writes a pretty good guid to engine mods and what to expect:

http://www.nightrider.com/biketech/download_manuals.htm
 

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STAND AND FIGHT!
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In my experience, a cam doesn't really make more power,
it just takes it from one RPM and adds it at another.
Displacement is good, and a turbo would be good.
 

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Touch my monkey....
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471 Posts
In my experience, a cam doesn't really make more power, it just takes it from one RPM and adds it at another.
Not totally true...;) It does exactly that, but also adds horsepower because of the addition of more fuel and air, AND because it's moving your power range to a more usable location.

Stock Harely cams have no "overlap" in them, making them meet EPA regulations and making their engines run cleaner. With that, and running low duration numbers (around 225* duration on most cams) not only makes the engine run cleaner, and sacrafices HPs. It's a safe cam duration tht gives low end grunt but sacrafices horsepower. The cams used in the 1991-1995 Harelys aren't worth the metal used in them to use as paperweights.

Less duration will produce more low end torque and less top end horsepower; more duration will produce less low end torque and more top end horsepower.

Cams basically have 3 different classes:

Low end: less than 235* duration.

Mid range: 235* to 250* duration.

Top end: 260* or greater duration.

I'd personally prefer a cam with good lowend and less HPs, only because I ride in that range, and have no need for balls-to-the-wall HPs, just riding around town, or the occasional trip. :p

Running a 95" kit, IMHO and using a stock, restrictive cam(s) is just silly. Adding the a higher duration cam adds more fuel through duration and lift, simply adding horsepower.
 

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Just passing thru
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Not totally true...;) It does exactly that, but also adds horsepower because of the addition of more fuel and air, AND because it's moving your power range to a more usable location.

Stock Harely cams have no "overlap" in them, making them meet EPA regulations and making their engines run cleaner. With that, and running low duration numbers (around 225* duration on most cams) not only makes the engine run cleaner, and sacrafices HPs. It's a safe cam duration tht gives low end grunt but sacrafices horsepower. The cams used in the 1991-1995 Harelys aren't worth the metal used in them to use as paperweights.

Less duration will produce more low end torque and less top end horsepower; more duration will produce less low end torque and more top end horsepower.

Cams basically have 3 different classes:

Low end: less than 235* duration.

Mid range: 235* to 250* duration.

Top end: 260* or greater duration.

I'd personally prefer a cam with good lowend and less HPs, only because I ride in that range, and have no need for balls-to-the-wall HPs, just riding around town, or the occasional trip. :p

Running a 95" kit, IMHO and using a stock, restrictive cam(s) is just silly. Adding the a higher duration cam adds more fuel through duration and lift, simply adding horsepower.
Dave,
I hope you plan on hanging out here forever. I love your tutorials! ;)
 

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STAND AND FIGHT!
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Great website.

OK Dave, and KB as well, you 2 have got my interest, tell me what you would do with my bike to make it more interesting, but with significant restrictions.

I'm maybe half way there, with the 95" kit, duals w/SE slipons, and low restriction intake, HD spec re-tune for higher redline, on a 2005 so I don't have O2 sensor control. (I actually kind of like the idea of O2 sensor control) I don't have any head work or cams. It's a fuel injected LowRider and never has a backseat rider or any serious load, so it's a relatively lightweight bike by the description on that web site.

I NEVER race, but I do run it hard fairly regularly, and I live for rolling the throttle on.
I NEVER drag race, hard launches away from stop lights are not my thing, I tend to wait for the first car to go so I can hide in his shadow.
I NEVER run it top speed, I have neither the stones nor the desire to see what 130 mph is like.

My hard use is almost always when coming up behind 4 cars bumper to bumper on my long 2 lane commute to work,
They're going 60 or 65, and I want to run 75, I do like the passing manuever being an excuse for a satisfying 10 second almost WFO burst that I don't intend to be to redilne, but it frequently is to the rev limiter.

I would NOT be happy with any significant decrease in cruise mode gas mileage. What has kept me from looking into further changes is being old enough to have done hot rod mods that more often than not hurt more than they help, or they help for WFO blasting but hurt cruise mode, low end and day to day driving.

I have actually considered SuperTrapp slip fits if I thought I could slightly soften the peaks of the exhaust note without hurting performance, I'm not wanting it quiet, but the very peaks of the POP! part of the exhaust note could be taken down a little and I wouldn't miss it.
Hard to spend $500 for such a minor change tho.'
 

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Touch my monkey....
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471 Posts
I'm maybe half way there, with the 95" kit, duals w/SE slipons, and low restriction intake, HD spec re-tune for higher redline, I don't have any head work or cams.

I would NOT be happy with any significant decrease in cruise mode gas mileage.

I have actually considered SuperTrapp slip fits if I thought I could slightly soften the peaks of the exhaust note without hurting performance, I'm not wanting it quiet, but the very peaks of the POP! part of the exhaust note could be taken down a little and I wouldn't miss it.
Hard to spend $500 for such a minor change tho.'
Ok.... few things...

You have a 95" kit.

A wiser man than I once said, "There's no substitute for cubic inches". Adding cubic inches to a motor is one of the easiest ways to add power. The second easiest way is to feed it. A cam helps do that. However, with that usually comes a price. Fuel mileage.

Cruise mileage wouldn't drop significantly, but there will be a decrease as you're using more fuel. The big drop occurs when performance mods are added to a machine, and the operator can't keep OUT of the throttle, enjoying the new found performance.:D

My RC51 got 130 miles to a 4.7 gallon tank, from the factory. After modifications, I got 90-95 out of a tank, and only 50-60 minutes of track riding before the "fuel" light came on.:p The bike had a Power Commander in it, that allowed me to add or delete fuel from anywhere in the rpm ranges. With the assistance of a dyno, I could tell, via torque, HP and with an exhaust gas analyzer, where the MAP needed to be adjusted to get more power.


The ways to feed YOUR bike are a little simpler than my carbed Harley, but basically the same principle: Give it the proper amount of fuel through the entire rpm rev range in order to produce peak HP. Simply: Your bike can be MAPped through the computer. Altitutde, exhaust and air intake are all things that effect this MAP. Despite popular belief, open air filters or open exhaust doesn't benefit all bikes, or styles of riding.

The proper cam with the proper MAP would definitely increase your torque and horsepower ranges, giving you what you want, with a small decrease in your fuel mileage. For highway riding, you're in the midrange already, and that's where you'd have the cruising power that you want. The sacrafice *might* be a tad off your bottom end, that you may or may not even notice.

I'm not positive about this, but I'm willing to bet that if Harley Davidson offers a "Performance tune" for certain modifications, it's conservative at best, when compared to a performance tune applied by someone that doesn;t have to adhere to EPA reglations or the Federal Government in any way, shape or form.

Headwork: Headwork definitely has it's advantages for flowing better intake and exhaust, but it's not manditory for most street bikes. There are 95" engines putting out very close to the 100hp numbers with stock heads. Head work is proof that there's always room for improvement, and always ways to squeeze more horsepower out of an engine. If you were looking for 100+ HPs, then it's almost a must... No sense building a high performance engine and leaving the intake system stock, as that's like making an athlete breath through a heavy winter quilt....

Exhaust: Exhaust is just as important as any part you can add to an engine. An engine is an airpump, and the FASTER air gets in and out, the more horsepower it makes.

People have a misconception that BACKPRESSURE is what is the most important, when in fact, it's exhaust VELOCITY. All things given, backpressure directly effects this. Case in point:

How many times have you seen guy with 2" drag pipes, and no baffles? If you were actually gotten a base run on a dyno BEFORE the addition of the straight pipes, using the stock exhaust, you'd have seen slightly less topend horsepower numbers, but better low end and midrange numbers. Open exhaust reduces exhaust velocity, reducing midrange power and torque, with only gaining a few topend horses.

When I installed the 2" drag pipes on my bike, I took it out for a ride. It was loud and had the worst dead spot in the midrange, and dogged off the line. I installed Big City Thunder baffles, and upped my main jet to 180 from 165, and it felt a whole lot better. Still a tad lean in the midrange.

I finally ended up installing my factory head pipe with crossover pipe (equalizes exhaust pulses and crossovers are proven to assist in low end horsepower and torque) but uses Cycle Shack tapered mufflers and opened the baffles up a tad. I left jetting the same and the difference is noticable, with constant pulling from idle to 5200 rpms. It's almost as loud, but despite adding a little more weight, It performs better.;)

I've read that 2-1 systems seem to make good numbers on a dyno, when compared to the 2-2 systems Harely is traditionally known for.

Popping out of exhuast: I've found this can be cause by two common things: Reducing backpressure and an exhaust leak. Popping on deceleration is common as you decrease backpressure and with some systems, is hard to avoid. I know what you're saying, as I love a good exhaust note, but can do without annoying noises and popping that attracts attention or makes my ride sound like a POS.

Screaming Eagle slip-ons are hollow cans, with inserted, stamped steel baffles (air deflectors) inside. They're nothing special, nor overly researched, when compared to Vance & Hines or a few other brands. I agree.....it's hard to swallow $500 for new cans for just a tad bit more performance, bling or benefit.

Long winded, I know..........:rolleyes: Nathang, I'm not so sure, in your case, that adding cams would make you happy, but in reality, I think it will.

`Nother good article: http://www.munising.com/harley_twin_cam.html


Although, I believe that it would deliver a noticable increase in your engine's performance without robbing you of too much fuel mileage. It's a personal choice. If you stayed with a cam (set) with a slight amount more duration and lift from stock, it would be enough to really wake the engine up with more fuel delivery and some much needed valve overlap. The last thing would be to apply the proper MAP for your engine, based on exhaust, CID, and intake modifications.

If you have the resources, and the extra money, don;t be afraid to have a dyno run or two performed to let you know exactly what you have now, and what if any benefit changes you make to your ride are doing. I say that "I notice a difference" when riding my bike after making modifications, but in reality, most people *think* a machine has more power when in fact, it's gained only noise. I refer to this as using the "Ass-Dyno 1000-i" :D
 

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COB
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I remember reading an article about 20 years ago about Nascar technology. At the time they were running 200 mph with 320cfm Holleys carbs. The gist of the whole article was that all the performance came from the head work.

There are practical limitations on horsepower on our V-twins due to how severe the power pulses can be in high HP, non counter-balanced motors. I have ridden 130hp Harleys that jaggle your teeth because the power pulses are so strong, yet there are guys out there with 150hp VRODS that don't mention it at all.

Interesting stuff. As some of you know from the other board, I love to discuss arcane tech talk!

So if you lower an R .........:D
 

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Touch my monkey....
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There are practical limitations on horsepower on our V-twins due to how severe the power pulses can be in high HP, non counter-balanced motors. I have ridden 130hp Harleys that jaggle your teeth because the power pulses are so strong, yet there are guys out there with 150hp VRODS that don't mention it at all.
I agree whole heartedly. The Harely V-twin is WWII technology, shared if not taken from the old radial airplane engines. It's old.. The twin cam angine was the best thing that ever happened to it, but it's still limited to it's abilities to produce usable horsepower and remain reliable.

The V-Rod is a breath of fresh air into Harely's heritage, redesigning the V-twin engine into something that's smoother, lower center of gravity, cleaner running, more horsepower producing and cooler running. I can't wait until 10 years from now when the hotrod guys start producing 300+ hp bikes that are street ridable, yet reliable......:D

I remember reading an article about 20 years ago about Nascar technology. At the time they were running 200 mph with 320cfm Holleys carbs. The gist of the whole article was that all the performance came from the head work.
When you start running V8 engines at their peak performance (8500+ rpms) headwork IS a huge deal. It's amazing the HPs they get out a motor using 320 cfm carbs. I had a 700cfm on an old Dodge that made 1/4th the HPs these guys make.....:rofl:
 

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I break stuff.
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Discussion Starter #15
Dave knows a lotta good stuff and explains it very well.
 

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Touch my monkey....
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Touch my monkey....
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471 Posts

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I break stuff.
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Discussion Starter #19
While I was at the shop, they showed me something else... a nitrous system that is 100% externally undetectable... I would lose 1/3 the capacity of one saddle bag but that doesn't matter cuz I've got more storage space on the bike than I generally use anyway (would just have to roll up my jacket in a smaller ball when wandering around off the bike).

Since I have no intentions of going back into Baby's motor once she's been sorted out... this may be a cost-effective means of satisfying my "itch"... What do you think?
 
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