JS Camshaft profile graphs (2012)

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Thanks Jim - It really helps see what you have there. Do you think the Axtel #3 would be about equivalent to the Combat (2S) cam? I'm just a country road rider but when I'm all alone I'm an incurable throttle addict and becoming worse.

Russ
 
Jim, I had Jim Mosher put in a Megacycle 5600 cam a year ago when he rebuilt my motor, his advise for a good around street cam just a bit more aggressive than stock 850 cam.

How does this compare more closely to which of the cam choices you have?

thanks
 
I run this cam. Almost like 3 cams in one.
Good off the bottom with only a slightly lumpy idle which is desirable to me (good around town).

Once 4000 is hit, it's a different experience, sort of like flipping a nitrous switch, sort of, (would love to try it at Grattan).

Over 6000, it become this non stop pull. I am not ready to go past 7000 and although the radius lifters make it possible, I would like some better valve springs (IF that was my intention). An ignition system with a rev limiter seem plausible.

This may or may not be an exageration but generally speaking, this has been my exoerience.
 
I have graphs of many of the popular cams along with the JS stage 2 cam. I people are interested and JS agrees I can post them next week. Jim
 
This people is most interested in JS's Norris D cam for flat lifters.
 
I also run the JS Stage 1 and concur with pvisseriii's comments. Great cam. Plenty of snap off idle, very strong mid range and has plenty of pull on top. I'm still breaking in new rings and a new lower end so I haven't gone much above 5K under WOT, but it's got a real power hit above 4K. Actually it's not a "hit" like you're coming on to a big cam, it's a very clean transition from strong to much stronger. The guys at the shop I use do a lot of Norton motors and they are really impressed with the cam.

IMO, this all comes with no penalty in driveability or economy. Idle is solid and the bike is very easy to ride around town or in traffic with excellent throttle response. My mileage is in the low 40's and that's with a lot of rolling into and out of the throttle during the break in period. After the break in period and I'm not constantly exercising the throttle, I expect that my mileage will be in the high 40's.
 
Sorry I fogged out on the tedium and attention to produce these graphs, thanx.
Been sending Peel's cam to you for a month+ now, dam dead deer, dead mower and smoking to death Trixie, set me back for the rifle drilling and head flow comparison. Don't sweat the graph, just teasing about your competence to take on lots of projects. Dyno Dave and vendors have it close enough to predict no detonation on 87 oct, if I behave. Lots of reasons picking Norris D, but a biggie was the low down weak tameness bleed off to 7.5:1 effective CR.
Boompf Boompf Boompf... baLATTT
 
hobot said:
Sorry I fogged out on the tedium and attention to produce these graphs, thanx.
Been sending Peel's cam to you for a month+ now, dam dead deer, dead mower and smoking to death Trixie, set me back for the rifle drilling and head flow comparison. Don't sweat the graph, just teasing about your competence to take on lots of projects. Dyno Dave and vendors have it close enough to predict no detonation on 87 oct, if I behave. Lots of reasons picking Norris D, but a biggie was the low down weak tameness bleed off to 7.5:1 effective CR.
Boompf Boompf Boompf... baLATTT

No tedium to it. I can graph yours if you would like. I just stick it in the CNC machine and push go. It spits out a graph in about 3 minutes. Accurate to .0001 in. Jim
 
Batrider
Yes the stage one (Axtell #3 copy) has similar preformance to the Combat 2S but a slightly wider powerband. I know because I raced both cams in the same bike at Willow Springs racetrack and ended up sticking with the Stage 1 Axtell #3 copy..

1 up 3 down
The Stage one is closest to the Megacycle 560-00

Hobot
The stage 3 is similar to but higher powered than the Norris D. Its about the most cam a Norton can handle.

See more comparisons and details at:

http://www.jsmotorsport.com/technical_CamLifters.asp

Yes Jim C you are welcome to post graphs. Everyone should note that Jim Comstock has a dealer account with JSmotorsport and all of our products are available through him when you have him rebuild your motor.

BTW
All the graphes for flat tappet cams can be found at the link below but the proportions (aspect ratios) are different.

http://atlanticgreen.com/camsurvey.htm
 
JS I ordered your Norris D flat tappet cam, hoping it was similar to D+. You have confused me by your post above say Norris D is less radical cam than the Axtell#3, yet your sites lists Norri D among the most radical offered. I'm hoping my 920 make the Norris D act like less radical cam in smaller engines. Also the 10.5 CR may help it idle as well as a bit of air force from blower. I only find Norris RX on DynoDave's site not the D or D+.

Ok comnoz, if that easy, I'll have Ken send cam to drill and graph and early CHO head for flow pecking order sense. Theres a couple of easy experiments in head I'd like ya to test. Do ya think if worth it to have cams Nitrided polished too? Where do you put the oil vents in the lobes?
 
hobot said:
JS I ordered your Norris D flat tappet cam, hoping it was similar to D+. You have confused me by your post above say Norris D is less radical cam than the Axtell#3, yet your sites lists Norri D among the most radical offered. I'm hoping my 920 make the Norris D act like less radical cam in smaller engines. Also the 10.5 CR may help it idle as well as a bit of air force from blower. I only find Norris RX on DynoDave's site not the D or D+.

Yes I sent you a copy of the Norris D (D+) grind for flat tappets and that will work well with a large displacement motor and mellow it out a little. The JS stage 3 cam is a higher power cam than te Norris D - not the Axtell #3. The JS stage 1 cam is a copy of the Atlas #3 but for radiused tappets. I don't sell flat tappet cams anymore because they don't last as long as cams for radiused tappets and the original Norton flat tappets are much too heavy.

The Norris D grind is listed on my site as being close to the JS stage 3 cam on the right side of the comparison chart here.
http://www.jsmotorsport.com/technical_CamLifters.asp

The Norris D grind (same as D+ I believe) is on the cam survey site - you just have to take the time to find it.

go to:
http://atlanticgreen.com/camsurvey.htm

then go to:
http://atlanticgreen.com/images/cam520.gif

The JS stage 3 has more lift and duration.
 
hobot said:
JS I ordered your Norris D flat tappet cam, hoping it was similar to D+. You have confused me by your post above say Norris D is less radical cam than the Axtell#3, yet your sites lists Norri D among the most radical offered. I'm hoping my 920 make the Norris D act like less radical cam in smaller engines. Also the 10.5 CR may help it idle as well as a bit of air force from blower. I only find Norris RX on DynoDave's site not the D or D+.

Ok comnoz, if that easy, I'll have Ken send cam to drill and graph and early CHO head for flow pecking order sense. Theres a couple of easy experiments in head I'd like ya to test. Do ya think if worth it to have cams Nitrided polished too? Where do you put the oil vents in the lobes?

I put the oil holes just before the quieting ramps at the base of the lobe. Personally I wouldn't nitride anything that is going to flex a lot like a Norton cam. Jim
 
I put the oil holes just before the quieting ramps at the base of the lobe. Personally I wouldn't nitride anything that is going to flex a lot like a Norton cam. Jim

Flex a lot? Our Norton cams? Hm learn something every day here, ugh. Ok thanx for the insight. On past Peel I had most everything including cam dry friction coated with Ti-oxide. Seems to wear off after a while though. Past Peel's tach needle disappearing event took off most the RH exhaust lobe in about 5 sec.
 
hobot said:
JS I ordered your Norris D flat tappet cam, hoping it was similar to D+. You have confused me by your post above say Norris D is less radical cam than the Axtell#3, yet your sites lists Norri D among the most radical offered. I'm hoping my 920 make the Norris D act like less radical cam in smaller engines. Also the 10.5 CR may help it idle as well as a bit of air force from blower. I only find Norris RX on DynoDave's site not the D or D+.

Ok comnoz, if that easy, I'll have Ken send cam to drill and graph and early CHO head for flow pecking order sense. Theres a couple of easy experiments in head I'd like ya to test. Do ya think if worth it to have cams Nitrided polished too? Where do you put the oil vents in the lobes?

JS stage 2 looks very similar to my Norris RX. Still putting the combat engine back together with this cam, so have not tried it yet. All around street race cam sounds like what I was looking for.
 
LIke I say I'm confused on camshafts going no brainer factory parts on my Combat but gone out of my mind on Peel. Any reviews of CR, displacement per profile and rpm preformance appreciated. I may be trying other cam if can't live with Norris D. I got to ride the 1200 over cammed Sportster I got the jump on by my wheelie launch avatar, it was miserable on the street and hwy intersections, bogged at sane throttle chugged a bit then BOWANGGG. Neck and and Neck though 2nd, but out horse powered my stock Combat about 80's mph 7-8 sec later as I hit 3rd.


I think Commando-ish engines have about reached their peak mechanical rpm power development. I believe there's more incremental improvements to be sought but less percentage help per new mod. So only special fuels and boost are left to play with the bigger boys that can't handle their power leaned much. Asymmetric cams would really shine for this use. comnoz has his roto rooter compressor and me a snail fan blower so a market is developing, I'm betting on softer power spikes to save traction. Too dang tight lifter bores to adapt roller lifters by modifying off the shelf items.
 
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