| Author | Message | ||
     Gohot |
1998 Buell Cyclone.........I'm thinking of going to Jim's roller rockers, the reason being, not only higher quality, but to cut down on the racket found in the 1203 motor.I'v been told by a fiew people that you just have to ignore the noise. Well yes, and no, I know how much noise is ok and when the sounds indicate problems such as wear and such. Having said that, I was wondering about if ratio rockers are a sound choice, as the name implies, increased preasure on lifters and cam lobes would be the concequence along with pushrods and rocker shafts. Also dialing in the valve spring lift for clearance. Stock or 1.7's, whats the view out there. My motor is the standard type stuff, ie exhaust, dynojet, S&S filter, with the addition of thunderstorm heads, pretty basic stuff. The other option is Andrews cams, and if I did that I would use non ratio rockers, but for now what is the concensus? The motor was entirely rebuilt with now just at 5,000 miles since, that is entirely except the rockers, everything else is done, pistons, cams,bearings,etc. etc,the works, $1200 worth, parts alone. | ||
| Limitedx1 |
im not a harley motor expert by any means, but i do have some experience with chevy small blocks. the theory is the same, the ratio will make the cam lift roughly around 32 thousands more(in a small block). so basically the only thing a ratio rocker will give you is a bigger cam without actually buying the bigger one. as far as wear, if you had the bigger cam in it the pressure would be the same, so my opinion is that the wear issue is notimportant. again, just relating my v8 experience to engine internals | ||
| Gohot |
sounds very logical, thanks Limitedx1..... | ||
| Hootowl |
I'm pretty sure most of the noise is not the rockers, it's the cam gears. Changing the rockers may not help you. | ||
| Krassh |
When I re-built my 80 CI in my 92 Electra Glide the noise actually increased due to the Jims roller Rockers I installed. | ||
| Beachbuell |
My buddy just rebuilt the motor on his 2001 M2L using mostly S&S and Andrews parts, this thing is a MONSTER! I don't have the exact specs or parts list in front of me, but I'll get a hold of it and post up. Bored, forged pistons, cams, flowed heads, roller rockers, D&D pipe, force wind A/C setup, carb jetted and a heavy duty clutch pack. This thing leaps off the ground in 1, 2 and 3 gears. He can chirp 2 and and 3 gear and launch it. SICK! I'm kinda scared of it! (Message edited by beachbuell on May 22, 2008) | ||
| Krassh |
The one I built for my 92 electra glide was J&E Forged 10.25 to 1 pistons, Dyna 2000 ignition/single fire coils, PR-2 Cam (Patrick racing), Jims Big Axle Lifters, Crane Pushrods, Jims Roller Rockers, NHRS Stage II heads, HSR42 Carb. This Glide had a real nice passing gear. Almost regret selling it as it had more power than my '07 96 CI Electra Glide. | ||
| Sparky |
Isn't the main reason for roller rockers to minimize side loading on the valve stem due to high lift cams swinging the rocker contact point in an arc? If so, long term valve guide life would be one consideration pro, but the other thing con is, ideally, one should strive to reduce valve train mass over stock. So unless roller rockers weigh less than stock rockers, I'd say negative to roller rockers, but that's just MHO. YMMV. | ||
| Krassh |
A roller rocker is a rocker assembly that uses bearings instead of metal sliding on metal. A cam/rocker assembly uses a normal cam, but the rocker has a wheel on the end of it like that of a measuring wheel, which rolls by the use of needle roller bearings. The amount of power required to spin a cam is surprisingly high, and it gets harder if stiffer valve springs are used, which are necessary to prevent valve bounce with aggressive cam profiles at high rpm. High lift cams and high pressure springs need the extra strength and reduced friction offered by quality roller tip rocker arms. Roller tip rockers significantly reduce valve side loading which extends valve and guide life. |
