measuring the exhaust lift

the intake lift was easy to measure but i cant seem to figure out how to measure the exhaust lobe.

anyone know how to measure the lift?[/b]

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..If yourt alking about the back under the cam lobes..I get them confused but.. Bend the tip of your feeler guauge, prob 1/4th to a half inch from the end, its the only way and the most recommended way to check them. If u dont wanna bend go buy pre bended ones

you actually measure under the rocker assembly and the valve itself.. not were the cam touchs the rocker arm assembly

you actually measure under the rocker assembly and the valve itself.. not were the cam touchs the rocker arm assembly[/b]

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I have no idea what you are talking about (becuz im still noob to the motor) but I measured the right spot as sseen in the hotcam video LOL. I guess what you said is what i meant to say. Isnt it under the cam where the buckets hit the bottom of the cam?

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you actually measure under the rocker assembly and the valve itself.. not were the cam touchs the rocker arm assembly[/b]

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I have no idea what you are talking about (becuz im still noob to the motor) but I measured the right spot as sseen in the hotcam video LOL. I guess what you said is what i meant to say. Isnt it under the cam where the buckets hit the bottom of the cam?
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on the intake yes but not on the exhaust.

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you actually measure under the rocker assembly and the valve itself.. not were the cam touchs the rocker arm assembly[/b]

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I have no idea what you are talking about (becuz im still noob to the motor) but I measured the right spot as sseen in the hotcam video LOL. I guess what you said is what i meant to say. Isnt it under the cam where the buckets hit the bottom of the cam?
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on the intake yes but not on the exhaust.
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Ooh ..what..Isnt the exhaust just out in the front you slide the feeler gauge in?. Yeah right under the rocker assembly. Where it hits the shims. Not sure how u couldnt measure that one, Im either not understanding or maybe he has them switched?

sorry guys i wasnt clear, im not talking about measuring vavle clearence.

im wanting to find the lift of the exhaust lobe. the cam is sitting on my desk and im using a mic and caliper.

sorry guys i wasnt clear, im not talking about measuring vavle clearence.

im wanting to find the lift of the exhaust lobe. the cam is sitting on my desk and im using a mic and caliper.[/b]

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Oooooh, Gotcha. Quadforce take it away

I think that you are supose to set a dial gauge up at 0 on the bottum side and then rotate to get a reading.. I would set it up in the carrier and maybe even bolt ot down to a piece of wood so that it would not move arounds and give false readings.. that may not be correct but that is the way I would try to do it.

You take what ever the measurement is on the lobe and times it by 1.4 I think. I forgot the number to times it by....Zips told me like 10 times by now, he knows. I do thinks its 1.4 though.....

sorry guys i wasnt clear, im not talking about measuring vavle clearence.

im wanting to find the lift of the exhaust lobe. the cam is sitting on my desk and im using a mic and caliper.[/b]

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the lift for the exhaust LOBE....if I am reading this right....is no different than measuring for the intake LOBE....

this is called 'cam lift'.....not 'valve lift'....if in fact this is what your wanting....

simply take a dial caliper....measure the lobe at its smallest point (diameter).....same as with intake.....and the billet 'should' be the same diameter on both intake/exhaust.... .then measure the lobe at its longest point (widest diameter).......... subtract the billet diameter from the max lobe height....and this is your CAM LIFT.......

then....if you want Valve lift......take Gar's advice and multiply this amount by whatever the rocker arm 'ratio' is....I think Gar mentioned 1.4:1.......I am not sure on this number.....


hope that helped.....

"cam lift" or "lobe lift" on the exhaust requires extra calculation because the rocker arm. You measure the "lobe lift" same as intakes but you have to multiply by the rocker arm ratio. I think its 1.9 or 2.0........I can check my notes at home and get back to you. I cant remember off hand.

thanks zips and king i knew there had to be a leverage calculation for the rocker arm but didnt know what it is or how to figure it out, the measurements i would have gotten for a rocker arm ass. would have been rough at best, which could easly get me off a few thousands.

450rr just so you know the base circles are not the same on intake and exhaust.

zips, if you can check your notes that would be great. thanks

i did some backwards math and came up with

total lobe height of 1.391 subtract base circle of 1.230 = .161 X rocker arm advantage of 1.945 = exhaust lift of .313

does that number sound right zips?

Your right Hawk....I was kinda speaking in general.....'most' bumpsticks have an equal base circle throughout.... the 'uni' cam is different cuzz the intakes utilize a standard lobe... whereas the exhaust is based off of a 'roller rocker' type.....


just out of curiosity.... why are we checking the valve lift?????

i wanted to try the 06 hrc cam after wednesday night track ride (i cased a triple and i think a little more bottom end will help the way i ride) so i dug out my cams and wanted to be sure i picked the 06 hrc.

i know the 04 hrc has 3 rings.
i measured the intake and it was right, but i couldnt figure out how to measure the exhaust and it bugged the chit out of me.
i picked up the 06 hrc second hand so i was also double checking to make sure it is a 06 hrc

Dang, banging off of triples Hawk......offa, your a better man than me! Sick stuff, I stay grounded usually....lol

king remember i came up short.

so does anyone know the multiplication number?