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Cam question....Please help.

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Old Jun 10, 2012 | 10:01 PM
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From: martinez
Default Cam question....Please help.

Hello all.I will start off with the short version.I have a 1987 heritage softail that has been making some noise off and on for awhile now and finally got to the point of sounding like **** was coming apart in the motor.i thought it was a stator but after tearing into it found that a lifter failed and chewed up the cam also.That leads me to my next question.I pulled the cam in the bike out and found no brand or size on it,but it does have a V stamped on the end of the lobe.Any idea what i have??I dont want to order a cam untill i know what i had first.Also the bike is pretty much stock other than the k&n air filter,s&s intake and thunder header.(well as far as i know anyway).Any one think a ev27 cam would be a good choice and still be able to run stock heads and valve springs ect.Thanks in advance...
 
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Old Jun 10, 2012 | 10:10 PM
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Yes the EV-27 is a good choice.
It was the first mod I did to my bike and have been very happy with it.
 
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Old Jun 11, 2012 | 03:46 AM
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Don't know what the cam you have at present is, but there is a noticeable difference between the lobes on a standard (pointyish) and an EV27 (more rounded) cam.

I fitted an EV27 to my '86 Heritage using standard valve springs, push rods and lifters. No problem.

Cannot say how happy I am, it is a different bike. '07 Twinkies cannot stay with me on acceleration, and when cruising around 75ish and you want to pass something, wow........
 
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Old Jun 11, 2012 | 05:05 AM
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If you use search for 'EV27', you will find it is probably the most popular cam in here.
 
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Old Jun 11, 2012 | 05:46 AM
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Just put one in my 95 fxstc and as said, it's a different bike. My old cam had a "N" stamped on it I think. Way more pointed than EV27.
 
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Old Jun 11, 2012 | 06:12 AM
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It's a stock cam, and any low duration bolt in cam will be a improvement. Ev27, evl3010, se4 etc
 
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Old Jun 11, 2012 | 07:08 AM
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I got my original cam out and it also has a "V" stamped on it.
It also has a blue dot on the gear which is relevant if not changing the gear from cam to cam.
Read this: http://www.andrewsproducts.com/PDF_files/CamEV80.pdf
Mine was a straight swap, gear and all, and no whine or problems. Also loads on flea bay.....

So Yeah, as gsxrboy96 said , it appears to be a stock cam.
 
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Old Jun 11, 2012 | 08:37 AM
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Please forgive my ignorance but I am trying to learn. I know the basic of what a cam is, but am trying to pick up what a better cam does for you. Can someone explain what it improves, I've seen posts about accelaration, but can someon simply explain how?

I would also be interested to learn how difficult replacing one is, do you have to tear the whole engine apart? Does it require any speciality tools?
 
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Old Jun 11, 2012 | 08:49 AM
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Originally Posted by Bleachey
Please forgive my ignorance but I am trying to learn. I know the basic of what a cam is, but am trying to pick up what a better cam does for you. Can someone explain what it improves, I've seen posts about accelaration, but can someon simply explain how?

I would also be interested to learn how difficult replacing one is, do you have to tear the whole engine apart? Does it require any speciality tools?
In a nutshell, the cam improves performance by having a higher lift and a longer duration of the valves being open.

The only thing thats close to a specialty tool would be feeler gauges and/or a dial indicator to measure camshaft end play.

You won't have to get that deep in engine disassembly if you go with adjustable pushrods. Use heavy duty bolt cutters to cut the stock pushrods. Otherwise you'll have to take the heads off.
 
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Old Jun 11, 2012 | 08:52 AM
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Our Evos had to comply with EPA noise and emissions regulations, so had very conservative timing, compared with optimum design. The valves open later and close earlier than optimum, so they are open for a fairly short time. Also the rate at which they open is quite slow. Twincams have to meet tighter regulations, hence probably have even worst cam timing, one reason they have been made bigger.

Cams intended to improve performance open the valves earlier and faster, hold them open longer and close them quicker. More extreme cams also open them further, in other words they have more 'lift'.

The benefit of these cams is they generate increased cylinder pressures, drive the pistons down harder, increase torque and hence power, so that the bike accelerates quicker and can go faster. They also generate more noise and can increase fuel consumption, hence exhaust emissions.

Hope that helps!
 

Last edited by grbrown; Jun 11, 2012 at 08:54 AM.
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