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A is a Megacycle 510-65 too much for street? #643884
03/11/16 11:14 pm
03/11/16 11:14 pm
Joined: Aug 2001
Posts: 4,420
Santa Barbara, California
KC in S.B. Offline OP

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KC in S.B.  Offline OP

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Joined: Aug 2001
Posts: 4,420
Santa Barbara, California
I have a set of new cams I bought years ago, and was thinking maybe I could use them. Megacycle cams # 510-65. Has anyone here used them? From the site:

For 650 or 750. Best all around street and road cam. Broad power band, mid-range and
top-end. TT style performance. Use modified pistons and springs. (Recommended by Motorcyclist Magazine)
510-65 .355" .355"292101 104.5 .163" in .150" exR45 btc/67 abc 72 bbc/43 atc
295 TDC LIFT

Looks like the lift is enough to require piston / valve relief and springs. That makes me wonder if this would be too much of a hotrod cam. Not 20 yr's old anymore........


Down to 1 BSA, 2 Triumphs, 1 '56 Chevy
Oops,.. add 1 '65 XLCH
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Re: A is a Megacycle 510-65 too much for street? [Re: KC in S.B.] #643889
03/11/16 11:55 pm
03/11/16 11:55 pm
Joined: Nov 2008
Posts: 2,866
Bishop, Calif.
D
desco Offline
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desco  Offline
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D

Joined: Nov 2008
Posts: 2,866
Bishop, Calif.
I've got the same spec sheet.Given todays shity gas it would not be as hot as it was in the day.
But, the hot rod is in the control of your right hand. Make the mods and go for it.
My 68 has the 510-05. It's a hoot to run it up to 7,000 rpm. Don't do it often but it's nice to know you can. I'm 71. When you quit living, you start dying.


1968 T120R
1972 T120RV
Any advice given is without a warranty expressed or implied.
Re: A is a Megacycle 510-65 too much for street? [Re: desco] #643997
03/12/16 5:14 pm
03/12/16 5:14 pm
Joined: Oct 2012
Posts: 4,181
Running from demons in WNY
Hillbilly bike Offline
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Hillbilly bike  Offline
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Joined: Oct 2012
Posts: 4,181
Running from demons in WNY
Originally Posted by desco
I've got the same spec sheet.Given todays shity gas it would not be as hot as it was in the day.


How does the fuel make the cam not as "hot"?


I take off bike parts until it doesn't function, then put on just enough so it functions
Re: A is a Megacycle 510-65 too much for street? [Re: KC in S.B.] #644026
03/12/16 7:59 pm
03/12/16 7:59 pm
Joined: Sep 2008
Posts: 855
Edgewater, Md
B
Blown Income Offline

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Blown Income  Offline

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B

Joined: Sep 2008
Posts: 855
Edgewater, Md
I have these cams in my dads 68 Bonnie with a 750 Routt Kit and 10:1 pistons. These cams are great in a Triumph!


1955 BSA Bantam D1 Plunger
1956 BSA A10RR Street and LSR Bike
1961 BSA C15S
1966 BSA spitfire
1969 Triumph T100C
1970 Triumph TR6R
1970 Triumph TR6C
1972 BSA Lightning LSR Bike
1974 Triumph T150V
Re: A is a Megacycle 510-65 too much for street? [Re: Hillbilly bike] #644043
03/12/16 10:15 pm
03/12/16 10:15 pm
Joined: Nov 2008
Posts: 2,866
Bishop, Calif.
D
desco Offline
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desco  Offline
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D

Joined: Nov 2008
Posts: 2,866
Bishop, Calif.
"hot" Poor choice of word for a short explanation. The cams would still do what they do but without the high octane leaded gas to produce whatever it does the performance would probably be somewhat reduced. Not as much need to be worried about a hotrod effect.
The Megacycle cams improved my 68 noticeably but the few tanks of av gas I ran through made it better still.


1968 T120R
1972 T120RV
Any advice given is without a warranty expressed or implied.
Re: A is a Megacycle 510-65 too much for street? [Re: desco] #644112
03/13/16 10:45 am
03/13/16 10:45 am
Joined: Oct 2012
Posts: 4,181
Running from demons in WNY
Hillbilly bike Offline
BritBike Forum member
Hillbilly bike  Offline
BritBike Forum member

Joined: Oct 2012
Posts: 4,181
Running from demons in WNY
According to specs on fuel company websites , aviation gas is actually slightly less BTU's than pump gas and a bit less dense....So power improvements not directly related to detonation might mean your bike engine is jetted a bit rich for pump gas....If longer duration cams are fitted to an engine with no other changes this will lessen the likelihood of detonation at low to moderate RPM's...
I ran my T120/750 on both non ethanol 91 octane pump gas and the same pump gas blended 50/50 with 107 MON octane leaded race gas...There was no difference in performance I could feel on the road...Of course the engine would detonate on the 91 non ethanol with too little rpm under load...
There's a lot of variables here and your experience may differ from mine..


I take off bike parts until it doesn't function, then put on just enough so it functions
Re: A is a Megacycle 510-65 too much for street? [Re: KC in S.B.] #644185
03/13/16 10:59 pm
03/13/16 10:59 pm
Joined: Jan 2008
Posts: 1,114
Noblesville, IN
Jack Adams Offline
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Jack Adams  Offline
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Joined: Jan 2008
Posts: 1,114
Noblesville, IN
I've been running those specs. on the street since the '90's. As usual,it is all in the combo. Jack

Re: A is a Megacycle 510-65 too much for street? [Re: KC in S.B.] #644470
03/15/16 11:06 pm
03/15/16 11:06 pm
Joined: Apr 2002
Posts: 716
Out There!
N
Nick Offline
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Nick  Offline
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N

Joined: Apr 2002
Posts: 716
Out There!
Be sure to check cam-to-crank clearance. When building my street 750 I ordered what, according to Megacycle's catalog, was one of their milder cams. However, when installed in the cases there was frighteningly little clearance between the cam and the crank, so I sent it back and exchanged it for their mildest cam, which I mated to 'R' followers. Very happy with the performance.


When people who should have known better cautioned me about the dangers of motorcycle racing, I always told them that a fear of death is nothing more than a fear of life in disguise.

Moderated by  John Healy 


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