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Lobe centers on Web 776 / 45 ?

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Daveeed:
I finally completed setting the cams on my 1397, JE 12.5, Ward headed, stock rod, lightened crank, N/A bike. I set cams so seldom, I always need to re-educate myself during the process.
I’m setting the bike up to run at Bonneville, 1/2, 1, and 1 1/2 mile events.
Anyhow, the cam card calls out 106 and 108. Guidance on this forum identified 109 / 110 or 110 / 111.
I am at 109 / 112.
I am seeking guidance on these lobe centers, should I take another swing? Or button this thing up?
Thank you in advance!

Daveeed

MJ Williams:
Last time around I did mine at 110-112 and the bike made a tiny bit more power over 10,000 than when they were at 108-110 but my speeds were slower. When I eventually get this thing back together I'm going to roll the cams back closer to that 106-108 range that Web wants.
I think I don't have the flow in my head to support that wide of cam timing so that may have something to do with the slower speed.
Going with the Web recommendations should give me some more compression and some more torque. Of course that is going to depend on my PTV clearance.
What is your PTV clearance now? 

RansomT:
My all motor bike (1340 cc), has a set of BIG webcams that call for 108/108.  I've moved them around a few times during different builds based on PTV clearances, it's got crazy high CR.  The bike has literally hundreds of pulls and I've found a couple of degrees in the cam timing makes little difference other than where peak occurs by a couple hundred RPM. I settled on 110/112, makes the same peak HP and TQ as 108/108, but at 200 RPM higher.  Pushing them higher to 112/114, peak HP remains the same at the same RPM but peak TQ drops just a bit. Bike peaks at 11,400-ish.  More power differences happens with the deck height than slight changes in the cam timing.

Daveeed:
Thank you guys! This dialogue is exactly what I need!
So I had kind of a setback, or I will call it lucky. I Found the clearance between the cam lobes and the cam covers to be a bit tight, like maybe 2 or 3 hairs. I ground the crap out of them, now I got .040”
And I also found my intake had slipped a tooth, giving me the opportunity to set my frickn cams one more frickn time. I have not checked the ptv yet, I gotta get the cams timed first.
Are you checking ptv with a tool from Brock, or a screwdriver, or clay?
Generally is it safer to run higher or lower centers?

Thank you in advance!
Daveeed

MJ Williams:
Brock's tool and dial indicator, I think CNC has one too. Higher is generally safer. I'm sure somehow you can get stupid and screw something up.

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