Need Cam Advice - SE 254E or SE 255 for a big bike?
#11
03-06-2011, 09:57 PM
No, not saying that at all. Others have noted that the 255s are good for low end torque from idle to 4000 rpm. I would expect a slight increase at the 4000 rpm range just based on those kinds of comments. I was saying that if you think about it, you are already at the high end of the usable range of these cams when you are at highway speed, especially if you ride in the states (I see you are from Canada.) - US freeway speeds are commonly 75 mph so 3000 rpm in 6th gear. Keep in mind that even if the 255s drop off at 4000 rpm, they are probably well past their torque peak at, say, 3500.
My recommendation would be to have a cam that has a usable torque curve over the actual range you ride in. You may, for example, want more power for passing so you might want maximum torque to come on at something just above your normal cruising rpm (i.e., 3500) as opposed to starting to go flat at that rpm. If you want to get by that car today, you will probably want to downshift to 5th, which will take your rpm well over 4000. If your bike is already sucking wind at 4000 rpm downshifting won't help as much as a cam that still has usable power at 4000 rpm.
Something else you need to keep in mind - it's a 6 speed bike, so you will be taking the rpm up through the torque curve everytime you shift. Do you want to feel it dropping off at 4000 rpm every shift? Maybe "No" maybe "Yes", I'm just saying, you need to honestly think about your riding style. Ride around normally and pay attention your tach - you may be surprised how often you rev it higher.
My recommendation would be to have a cam that has a usable torque curve over the actual range you ride in. You may, for example, want more power for passing so you might want maximum torque to come on at something just above your normal cruising rpm (i.e., 3500) as opposed to starting to go flat at that rpm. If you want to get by that car today, you will probably want to downshift to 5th, which will take your rpm well over 4000. If your bike is already sucking wind at 4000 rpm downshifting won't help as much as a cam that still has usable power at 4000 rpm.
Something else you need to keep in mind - it's a 6 speed bike, so you will be taking the rpm up through the torque curve everytime you shift. Do you want to feel it dropping off at 4000 rpm every shift? Maybe "No" maybe "Yes", I'm just saying, you need to honestly think about your riding style. Ride around normally and pay attention your tach - you may be surprised how often you rev it higher.
It depends on the way you tune you bike. I have no drop off in power that i notice at all, I have been above 6K rpm when tuning my bike and she pulls hard from idle all the way to the top, I was also turned off by this statement when i was looking for cams but found that this is not the case, I do however have a RK and this maybe the difference but consider the HP to weight ratio with the 254E you may get more HP but less torque this will work with a lighter bike but your UC will move alot better and quicker with more torque that is offered by the 255's.
#12
03-06-2011, 10:19 PM
Some contend they "die after 4000 rpms" and so forth, but this isn't true. They produce power all the way up to the 6200-rpm redline, and more than the stock cams, but just not as much as the 254e's likely would. Their forte is in the 2000-4500 rpm range.
#13
03-06-2011, 10:35 PM
Outstanding HDF Member
255 cams
I agree...I have 255 cams and they are a great low end torqe cam. I have found out when on the highway you will find yourself not having to downshift to pass trucks...just twist the throttle and go. It's very rare I need to ride over 4500 rpm's.
#14
03-06-2011, 10:53 PM
#15
03-06-2011, 11:20 PM
Just about any mild, bolt in cam will return a noticible increase in power compared to the stock smog cams. The neg 8* overlap is the big killer with the stock cam profile. Add a little overlap and a bit more duration to the stock cams and you'd make noticeable gains. Lots of guys run the 255 cams and are happy with them. They're not my favorite for the 103 motors, but I'd put them in a 96 in a heartbeat.
Try to pick a cam that results in a corrected compression ratio of about 9.2:1, and you'll have good throttle response at all rpms, it will be easy to tune, and not prone to detonation.
Try to pick a cam that results in a corrected compression ratio of about 9.2:1, and you'll have good throttle response at all rpms, it will be easy to tune, and not prone to detonation.
#16
03-07-2011, 12:02 AM
I used to run andrews 21's and everybody said "no go good die after 4500 etc" I found it much more enjoyable to have good pulling power from 60-100 vs 80-120. Baby cams give the most in the range most of us ride. If there were no dynos smaller cams would be more popular.
Anyway, I agree with you and think most who criticize the "baby cams" haven't ridden a bike with them installed and witnessed their practical virtues. Of course some will get hung-up on cam specs and peak-HP/TQ values alone, but sometimes a real-world, seat-of-the-pants experience is what it takes to make it really clear. Without that they may never understand.
#17
03-07-2011, 12:22 AM
Lots of guys run the 255 cams and are happy with them. They're not my favorite for the 103 motors, but I'd put them in a 96 in a heartbeat.
Try to pick a cam that results in a corrected compression ratio of about 9.2:1, and you'll have good throttle response at all rpms, it will be easy to tune, and not prone to detonation.
Try to pick a cam that results in a corrected compression ratio of about 9.2:1, and you'll have good throttle response at all rpms, it will be easy to tune, and not prone to detonation.
Last edited by iclick; 03-07-2011 at 12:25 AM.
#18
03-07-2011, 12:51 AM
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I'm running a 103 with 255's/Baisley Super Stock heads 9.8 compression with SE Fatshotz
These cams were recommended by Baisley with my 2010 ultra. I ride two up and full gear about 8 thousand a year, the rest of the miles are solo.
I love this setup. Great lowend torque and with the heads being ported, etc., they bike runs strong up way past 4000. The heads are the thing to do to stretch the power curve!
These cams were recommended by Baisley with my 2010 ultra. I ride two up and full gear about 8 thousand a year, the rest of the miles are solo.
I love this setup. Great lowend torque and with the heads being ported, etc., they bike runs strong up way past 4000. The heads are the thing to do to stretch the power curve!
#19
03-07-2011, 06:21 AM
Road Captain
I just installed the 245e's....the 254e's are a newer cam and alot of folks are just getting to "know" it. I would tell you how my bike performs but there is alot of snow on the ground here...still have to wait for the thaw before I take her out on her not so maided voyage with new cams...I will keep you posted if you are interested.
#20
03-07-2011, 06:35 AM
Seasoned HDF Member
When i compared cams for my bike i bought a set of SE255 and a set of ANdrews 26H and put them side by side....Andrews was a bit more agressive but still i use my torque more than HP at low end and she pulls...The 255 looks to be about the same so with all the positive you hear of the SE255 go for that one ...Believe me you want the lower useable power...2300 rpm this weekend in 6th gear going uphill and she pulled and pulled....i rarely go over 4000 RPM in normal riding...I have a set of 255 that i may try just for the hell of it and now that i know how to do it myself i can do it in about 2-3 hours with a little Whiskey break. But enough rampling...Go with the 255 you will be happy....