When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Engine Mechanical TopicsDiscussion for motor builds, cams, head work, stripped bolts and other engine related issues. The good and the bad. If it goes round and around or up and down, post it here.
My bad, I missed the pipe change. I wish the OP would not have changed cams and pipe at the same time. A pipe or cam change only and a couple of pulls would have revealed something that might have been helpful in sorting out the OPs motor. In situations like this, changes should be made one step at a time. A full tune is not required to verify the effect of the change, just a couple of pulls will tell the story.
I know you like the Pro Streets and you are right, I believe there are better choices and I will tell you why. As a point of reference, I just scrolled through 150 dyno sheets on another forum and found two with the Pro Streets; both were 124" builds; empirical data that clearly shows the Pro Streets are not a popular choice. However, I did find it curious that the three 124" builds all ran Bassani pipes; two with Pro Streets and one with the RRII. In and of itself, the data doesn't mean that the Pro Streets don't perform but it does support that the Pro Streets are not often selected for performance motor upgrades. Which begs the question of why they are not often selected and that is a question I cannot answer. However, the data would point me to the other pipes that are more often selected with results that have been recorded as a basis for considering an alternative.
A long winded way of saying that I can't say whether the Pro Streets are the right pipe for the OP or not; they have worked out well for your particular configuration. However, by relying on available data I am quite comfortable recommending other systems for the OP's consideration. A moot point now that the OP has installed the Pro Streets but just wanted to clarify the reason why I am undecided about the Bassani Pro Street pipes.
I am anxious to see accurate compression data; maybe when we have that, we can help the OP sort out his motor.
Alright, I got what I assume are the most accurate CCP numbers I'll get with the easy starts. I got just about 180 in the front, and around 175-8ish in the rear. Before I tried that, I took reading the standard way and got 140 in the front and 132ish in the rear. Since I had her warmed up, I checked for sumping, I only got about 4ozs out.
I called the techs at S&S and talked to them about the two poor dynos. They transferred me to their tuner guy. He was surprised at both dynos. He said with the MR103's and everything else I've got, I should be seeing around 110hp and 115torque at least. He wanted me to check for sumping(done) and wanted me to tear into the cam chest again and verify that the inner gears are the proper front and rear gears. He said in the past that they have both been sent out with fronts. So, I guess I'll be going back into the cam chest.....
Alright, I got what I assume are the most accurate CCP numbers I'll get with the easy starts. I got just about 180 in the front, and around 175-8ish in the rear. Before I tried that, I took reading the standard way and got 140 in the front and 132ish in the rear. Since I had her warmed up, I checked for sumping, I only got about 4ozs out. I called the techs at S&S and talked to them about the two poor dynos. They transferred me to their tuner guy. He was surprised at both dynos. He said with the MR103's and everything else I've got, I should be seeing around 110hp and 115torque at least. He wanted me to check for sumping(done) and wanted me to tear into the cam chest again and verify that the inner gears are the proper front and rear gears. He said in the past that they have both been sent out with fronts. So, I guess I'll be going back into the cam chest.....
Those numbers look about right for your setup with the MR103 cams and intake close at 33*. A 106, .045" head gasket, 89cc chambers, -3cc dome volume (WAG) and average deck height of -.006" shows 185psi at sea level. You are at sea level so the 180ish number is not far off.
Even so, the last dyno numbers should have been better at that compression. Have to look elsewhere, I think the compression mystery is solved.
I am not sure I understand how the gear question. There is no way inners can be confused or interchanged with outers or visa versa. Perhaps I don't understand what the S&S tech is saying.
Those numbers look about right for your setup with the MR103 cams and intake close at 33*. A 106, .045" head gasket, 89cc chambers, -3cc dome volume (WAG) and average deck height of -.006" shows 185psi at sea level. You are at sea level so the 180ish number is not far off.
Even so, the last dyno numbers should have been better at that compression. Have to look elsewhere, I think the compression mystery is solved.
I am not sure I understand how the gear question. There is no way inners can be confused or interchanged with outers or visa versa. Perhaps I don't understand what the S&S tech is saying.
What the tech was saying is that there is a front and rear inner gear. He said the gears have gone out before with two front inner gears pressed on the cam. I guess the part numbers on the inner gears end in -R and -F to designate front and rear gears. Something I never thought to look at......
He also said that he had 570's in his bike and was going to swap to MR103's because they typically produce the same hp with more torque. Not sure, but he's supposed to be the man....
What the tech was saying is that there is a front and rear inner gear. He said the gears have gone out before with two front inner gears pressed on the cam. I guess the part numbers on the inner gears end in -R and -F to designate front and rear gears. Something I never thought to look at......
He also said that he had 570's in his bike and was going to swap to MR103's because they typically produce the same hp with more torque. Not sure, but he's supposed to be the man....
Got it! The rear gear rotates in the opposite direction of chain driven cams so, if a front gear is on the rear cam I suppose the way the teeth are cut there could be some parasitic loss of power but I would think that there would be some noise associated with gears installed that way. Anyway, worth checking. However, if the gears were installed on the cams when you received them, S&S should bear some responsibility for your problem. Keep us posted.
The MR103 intake closes at 33*; the 570 at 40* which would explain more torque from the MR103s and pulling the curve to the left; not sure about same HP though.
The MR103 intake closes at 33*; the 570 at 40* which would explain more torque from the MR103s and pulling the curve to the left; not sure about same HP though.
That's exactly what I thought.....the 570 Will out perform the 103 in the 4-6k range.....
Got it! The rear gear rotates in the opposite direction of chain driven cams so, if a front gear is on the rear cam I suppose the way the teeth are cut there could be some parasitic loss of power but I would think that there would be some noise associated with gears installed that way. Anyway, worth checking. However, if the gears were installed on the cams when you received them, S&S should bear some responsibility for your problem. Keep us posted.
The MR103 intake closes at 33*; the 570 at 40* which would explain more torque from the MR103s and pulling the curve to the left; not sure about same HP though.
Well, I think I'm making some progress. I spoke with S&S' tuner, he figures he's got the answer. According to him, and it makes perfect sense, the heads that were recommended to me were the 89 cc heads. He says that with those heads, I'm down to 9.7 to one comp ratio, this low ratio is why my numbers are so low. Because I purchased what was recommended by their techs, they've agreed to CNC the heads, taking out about 4cc. According to his calculations, this should bring me up to about a 10.3 to 1 ratio, where I want to be to make power with the MR103's. What are you thoughts there?
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Slideshow: The bar-and-shield logo shows up on far more than motorcycles, some of the company's most unexpected products have nothing to do with riding.
Slideshow: From the troubled AMF years to modern misfires, these bikes earned reputations for reliability issues, questionable engineering, or disappointing performance.
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Slideshow: The Swiss custom shop has taken a Harley Softail and stretched it into something so long and low that it looks closer to a rolling sculpture than a conventional motorcycle.
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Slideshow: A standard cruiser becomes an intricate metal canvas in the hands of a Swiss custom house known for pushing Harley-Davidson platforms far beyond their factory brief.