cams
Does anyone have an opinion on H-D high preformance 251 cams ? I understand they start to pull at lower rpm. The 257 has a higher mid and upper power band ?? I have to go with a chain drive much to my chagrin.
As I stated in a previous post, I put in S&S 585 grear drive cams, 3 different set's , there was loud motor noise with each set. I had the stock cams put back in (chain drive) no noise , no problem.
I was going to leave it because it ran ok, but it's a dog now with big heads and cylinders. I just don't want to buy another gear drive and have the same problem. I was told that if I go with Harley Preformance chain drive cams ( I know that's all they make ) that would more than likely take care of my problem. I'd be more than satisfied with power on the lower end that barks at 2,ooo-3,500 - 4,000 rpm .
I don't know what else to do. It's a new 2005 FLTR and I know Harley won't stand behind it with anything other than Harley parts.
Thanks for any input. Jmedn - Milwaukee
As I stated in a previous post, I put in S&S 585 grear drive cams, 3 different set's , there was loud motor noise with each set. I had the stock cams put back in (chain drive) no noise , no problem.
I was going to leave it because it ran ok, but it's a dog now with big heads and cylinders. I just don't want to buy another gear drive and have the same problem. I was told that if I go with Harley Preformance chain drive cams ( I know that's all they make ) that would more than likely take care of my problem. I'd be more than satisfied with power on the lower end that barks at 2,ooo-3,500 - 4,000 rpm .
I don't know what else to do. It's a new 2005 FLTR and I know Harley won't stand behind it with anything other than Harley parts.
Thanks for any input. Jmedn - Milwaukee
Dunno much about the S/E cams....
The S&S gear drive, properly setup, should not be any more noisey than the HD chain drive setup. In fact, they are often quieter! I know... I have heard plenty of "noisey" gear drive installs, but if the installer reads AND follows the installation directions, they will not be noisey. There is a certain amount of lash required in order for them to mesh correctly and run quietly. If the lash is not right, all you have to do is call the gear "supplier" (S&S, or Andrews, or whomever you bought them from). THere are over & undersized gears that resolve this problems.
I have used the gear drive set up in two of my own bikes and it's a non-issue, but I know of some that really should have called for a gear swap.
I'm sure someone else can offer feedback on the S/E cams....
Good luck Dude!
The S&S gear drive, properly setup, should not be any more noisey than the HD chain drive setup. In fact, they are often quieter! I know... I have heard plenty of "noisey" gear drive installs, but if the installer reads AND follows the installation directions, they will not be noisey. There is a certain amount of lash required in order for them to mesh correctly and run quietly. If the lash is not right, all you have to do is call the gear "supplier" (S&S, or Andrews, or whomever you bought them from). THere are over & undersized gears that resolve this problems.
I have used the gear drive set up in two of my own bikes and it's a non-issue, but I know of some that really should have called for a gear swap.
I'm sure someone else can offer feedback on the S/E cams....
Good luck Dude!
Gear drive will always make more noise than chain. Always. It's just a function of the gear mesh. By changing the gear pitch, and making sure they mesh properly you can mitigate the noise. But it's always going to make more noise than a properly set up chain. That's why H-D uses the chain instead of a cheaper and less complicated gear drive.
The 257 cam has an early intake valve closing like the 203, 204, and stock cams. That means it will work well with stock or slightly higher compression. If your compression is >10:1 and you live at low altitude, that could be a problem. You effective cylinder pressures could be too high. The early valve closing also places your power band fairly low just like you want.
The duration is a little long at 252/260*. That will extend the power band a little high without being hard to live with. Still get a fairly smooth idle and good low rpm performance, although not a stump puller.
The valve lift is kinda high at .569. Unless you've modified your stock heads, this may be too much lift. But the higher lift gives the engine a feel of more duration at higher rpm's. Also, at these valve lifts you really need to consider roller tip rockers. The side loads start to get on the extreme side for a daily rider.
For a simple bolt in cam, you might consider the 211.
Also, doesn't S&S make bolt in chain drive cams?
The 257 cam has an early intake valve closing like the 203, 204, and stock cams. That means it will work well with stock or slightly higher compression. If your compression is >10:1 and you live at low altitude, that could be a problem. You effective cylinder pressures could be too high. The early valve closing also places your power band fairly low just like you want.
The duration is a little long at 252/260*. That will extend the power band a little high without being hard to live with. Still get a fairly smooth idle and good low rpm performance, although not a stump puller.
The valve lift is kinda high at .569. Unless you've modified your stock heads, this may be too much lift. But the higher lift gives the engine a feel of more duration at higher rpm's. Also, at these valve lifts you really need to consider roller tip rockers. The side loads start to get on the extreme side for a daily rider.
For a simple bolt in cam, you might consider the 211.
Also, doesn't S&S make bolt in chain drive cams?
Actually, the 257 has a very late intake close at 48 degrees. If you really, REALLY want low and mid-range torque, and HAVE to have a Screamin' Eagle cam set, then the 204, which closes the intake at 34 degrees, is the only choice, assuming you're close to stock compression. The earlier the intake closing, the earlier on the dyno chart you make your power. Once you get above a 34 intake closing you have to hit 3000 rpm or so before you're on the cam. 3000 rpm in top gear on a 5sp Harley is about 70mph.
And when you twist the throttle at 70 mph to get around that big semi, you have absolutley NO problem getting around them and it doesn't matter whether you're one up, two up, two up pulling a trailer,,,,,it just don't matter. That's what I love about it. I don't need a qtr. mile racer, I want a road boss and that's what the 257's give me. Each to his own.[sm=gears.gif]
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