103 upgrade disappointing
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I was just being a clown. I couldn't pass that one up! LOL
Road Captain
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From: In Garage
Oops sorry I thought you guys were looking to get the most from your Harleys. Didnt know you were just looking for peak numbers. :]
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From: The Internet (& Dyer, Indiana)
The other LSA numbers he was touting would put the power band in too narrow of a range for our purposes. That's why harley riders don't go that route, only the racer guys.
Road Captain
Joined: Aug 2009
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From: In Garage
Tighter the lobe separation (numericly lower) more narrow the power band.So 100 LSA will have a more narrow power band then a 105 LSA.I mensioned the stock cam LSA and over lap in the other post. The info is wrong the real numbers on the stock cam is 109 LSA and -8 overlap [(non)this is apace the engine is not using].
Banned
Joined: Sep 2009
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From: The Internet (& Dyer, Indiana)
Tighter the lobe separation (numericly lower) more narrow the power band.So 100 LSA will have a more narrow power band then a 105 LSA.I mensioned the stock cam LSA and over lap in the other post. The info is wrong the real numbers on the stock cam is 109 LSA and -8 overlap [(non)this is apace the engine is not using].
Usable for cruising the hills without the headaches of a radical cam, and still allows for some play near the rev limiter. Low end grunt that comes on immediately, with mid and top end power as well. Ideal for me!
Your previous analogy that we are backwards because the "racers" like the higher LSA's and Harley riders don't,..... leaves out one HUGE difference.
How many car and Jap bike racers are limited to 6200 rpm?
HDF Community Team
Joined: Jun 2006
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From: san antonio
Originally Posted by N-gin
Hmph, all these posts and no one has looked at lobe separation.
I have attached a dyno chart to make the point. This build uses one of the cams you site in your post as a cam that "is good for peak #s for a short period of time but quickly fizzles out." Please show me where this cam is peaking early or fizzling out.
Most Harley cams will hold their peak TQ for 1000rpms, so the decision is where do we want the peak, center left, center or center right. Much more to the criteria than LSA goes into that decision.
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Road Master
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From: n
read this whole thread and seems like choosing cams is like choosing the best oil. I found it all very entertaining even though it sounded quite serious. I have a 103 with SE255 cams and I don't know what that means, but it sounds like Doc probably does. I have one of those SE spring gizmos too and I like the way the clutch feels. I do enjoy looking at the scenery though. :-) I'll go back to reading the less technical stuff now.
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Joined: Sep 2009
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From: The Internet (& Dyer, Indiana)
read this whole thread and seems like choosing cams is like choosing the best oil. I found it all very entertaining even though it sounded quite serious. I have a 103 with SE255 cams and I don't know what that means, but it sounds like Doc probably does. I have one of those SE spring gizmos too and I like the way the clutch feels. I do enjoy looking at the scenery though. :-) I'll go back to reading the less technical stuff now.
LOL I think you can be safe in assuming that cam selection is a few notches up from choosing oil. A few big notches up.
Poor selection here can give you big disappointments, where as you won't even notice a difference with oil.
A good example would be YOU racing your 255's against anybody near the rev limit. Your cam is designed for cruising, great low end torque. But you have no power at the high rpm's.
You don't race, so that don't hurt you.
Just don't try to race or you will be disappointed.
Your cam is perfect for your application, so don't take this as a slam. Many happy campers with that cam, because it is a good one.
.
Last edited by Faast Ed; Feb 7, 2011 at 05:01 PM.