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Discussion Starter #1
Ok guys so I’ve done the big bore kit on my 88” twin cam and installed new S&S crank boosting it up to 107“ . Runs like bat out of hell too. We ported the heads, new big bore kit, new S&S camplate and oil pump, and pushrods, fueling race lifters, T-Mann 590G gear drive cam. (starte$ with woods tw8g). So T-Mann 590 gear drive cam, hpi 55mm throttle body, scorpion clutch, new compensator,sprockets,chain, just installed 6 speed bolt in conversion kit, . S&S roller rockers, rocker lockers. So we did the build and could not get rid of top end noise With the woods tw8g cam so switched to the t-Mann 590G. This did quiet it down. Then 8 switched from S&S premium lifters to fueling race lifters. That helped some. Regardless I have done every test, checked for clearance nothing is hitting no where. I can not figure this out. I know they all make noise but not like this. It sounds like something’s wrong. I’ve had 5 or 6 bikes in last 10 or so years and harleys custom choppers whatever never have I had this noise. It sounds lik3 it’s hitting but it’s not. I’ve ch3cked 3 times. Any suggestions would be great. I’ve done all the normal test. 3 and 4 times. I also have really high compression. I’m pumping about 208PSI per jug. Doing a leak down test I had 5% up front and 8% in the back.
thanks
Brian
2006 Electra glide.
 

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That's 14.4 to one compression ratio. None of the octane charts I could find go over 12 to one. What kind of gas are you burning? 110 octane is 12 to one.
 

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Discussion Starter #5
They say with the cams I have and 208psi each jug is at about 10;1;1 compression I’m running best gas I can get. I used thundermax and adjusted my throttle position vs RPm and was able to get it to stop pinging. I also found that as the engine expanded the outer part of my crankshaft gear was ever so slightly hitting the cam cover and causing a heck of racket. Then we also used some fueling race lifters and she’s sounding great now.
 

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208 divided by 14.4 atmospheric pressure is 14:4 compression ratio. Gasoline octane charts end at 12:1 which requires 110 octane gas.
 

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I think there is a mis-communication going on here, one person is talking about static (mechanical) compression, and the other is talking about running compression. Octane requirements come from static compression.
 

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208 PSI is at the lower end of diesel compression ratio. If it was measured with a gauge in a shop then 208 is excessive. What is the measured compression?
 

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im sure most of you know this, but,, the mechanical compression is a fixed number based on swept volume divided by chamber volume..
the running compression is greatly affected by the cam shaft/s,,, ive seen 10.2 mechanical turn out 250psi cranking,,, due to using a tiny motor torque cam in a 10.2-1 117"... leading to hard to impossible starting,, eating starters and batteries, losing so many teeth on the ring gear it needs a dentist, compensator failures,,, and so on...detonation with any throttle input... cant be heard over the fishtails, and the genius's solution? add comp releases,, what genius
 

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Discussion Starter #12
I just went off what I was instructed. Here’s a photo from the recommendation for the cam chose. It’s running good now. Sounds great, runs very strong so I’m pretty happy. I may have said something wrong or something. I don’t know But it worked out and that what counts right
 

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Of course then think about power adders: Nitrous Oxide, super chargers, turbo chargers. We take those 2.0 Ectotec motors, put them on alcohol, add a 104mm turbo, set it for 60 psi of boost, and get over 1500 hp. out of them.
 

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00 Road King, 00 Ultra, 98 Fatboy, 08 Goldwing
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Ok guys so I’ve done the big bore kit on my 88” twin cam and installed new S&S crank boosting it up to 107“ . Runs like bat out of hell too. We ported the heads, new big bore kit, new S&S camplate and oil pump, and pushrods, fueling race lifters, T-Mann 590G gear drive cam. (starte$ with woods tw8g). So T-Mann 590 gear drive cam, hpi 55mm throttle body, scorpion clutch, new compensator,sprockets,chain, just installed 6 speed bolt in conversion kit, . S&S roller rockers, rocker lockers. So we did the build and could not get rid of top end noise With the woods tw8g cam so switched to the t-Mann 590G. This did quiet it down. Then 8 switched from S&S premium lifters to fueling race lifters. That helped some. Regardless I have done every test, checked for clearance nothing is hitting no where. I can not figure this out. I know they all make noise but not like this. It sounds like something’s wrong. I’ve had 5 or 6 bikes in last 10 or so years and harleys custom choppers whatever never have I had this noise. It sounds lik3 it’s hitting but it’s not. I’ve ch3cked 3 times. Any suggestions would be great. I’ve done all the normal test. 3 and 4 times. I also have really high compression. I’m pumping about 208PSI per jug. Doing a leak down test I had 5% up front and 8% in the back.
thanks
Brian
2006 Electra glide.
Ok guys so I’ve done the big bore kit on my 88” twin cam and installed new S&S crank boosting it up to 107“ . Runs like bat out of hell too. We ported the heads, new big bore kit, new S&S camplate and oil pump, and pushrods, fueling race lifters, T-Mann 590G gear drive cam. (starte$ with woods tw8g). So T-Mann 590 gear drive cam, hpi 55mm throttle body, scorpion clutch, new compensator,sprockets,chain, just installed 6 speed bolt in conversion kit, . S&S roller rockers, rocker lockers. So we did the build and could not get rid of top end noise With the woods tw8g cam so switched to the t-Mann 590G. This did quiet it down. Then 8 switched from S&S premium lifters to fueling race lifters. That helped some. Regardless I have done every test, checked for clearance nothing is hitting no where. I can not figure this out. I know they all make noise but not like this. It sounds like something’s wrong. I’ve had 5 or 6 bikes in last 10 or so years and harleys custom choppers whatever never have I had this noise. It sounds lik3 it’s hitting but it’s not. I’ve ch3cked 3 times. Any suggestions would be great. I’ve done all the normal test. 3 and 4 times. I also have really high compression. I’m pumping about 208PSI per jug. Doing a leak down test I had 5% up front and 8% in the back.
thanks
Brian
2006 Electra glide.
Ok guys so I’ve done the big bore kit on my 88” twin cam and installed new S&S crank boosting it up to 107“ . Runs like bat out of hell too. We ported the heads, new big bore kit, new S&S camplate and oil pump, and pushrods, fueling race lifters, T-Mann 590G gear drive cam. (starte$ with woods tw8g). So T-Mann 590 gear drive cam, hpi 55mm throttle body, scorpion clutch, new compensator,sprockets,chain, just installed 6 speed bolt in conversion kit, . S&S roller rockers, rocker lockers. So we did the build and could not get rid of top end noise With the woods tw8g cam so switched to the t-Mann 590G. This did quiet it down. Then 8 switched from S&S premium lifters to fueling race lifters. That helped some. Regardless I have done every test, checked for clearance nothing is hitting no where. I can not figure this out. I know they all make noise but not like this. It sounds like something’s wrong. I’ve had 5 or 6 bikes in last 10 or so years and harleys custom choppers whatever never have I had this noise. It sounds lik3 it’s hitting but it’s not. I’ve ch3cked 3 times. Any suggestions would be great. I’ve done all the normal test. 3 and 4 times. I also have really high compression. I’m pumping about 208PSI per jug. Doing a leak down test I had 5% up front and 8% in the back.
thanks
Brian
2006 Electra glide.
I have a similar set up with my 00 Road King. 106", .585G cams and complete S&S valve train. I have tried many things over the years and have come to the conclusion that it is going to be noisy. I also have a 00 Ultra(95") with 510G cams and S&S valve train. It is a little noisy also. Both bikes run great and I have 69K and 105K on them. I have just learned to live with it. If you find a way to make the quiet, let us know. Sorry I have no advice to offer.
 

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Discussion Starter #16
Thank you so much. I’ve double triple and quadrupole checked and I did find I was hitting a little on camplate cover and when I grinded that down it quieted down a lot. I also switched back to regular oil instead of synthetic and that made a huge difference. My bike just don’t care fir synthetic. I’m in same boat now. She runs great. Turn up the stereo and let’s roll.
 
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