[secondchance]

Ok,here we go again,I know but bear with me,I just want to learn more about cams,lift,duration......Went riding with a friend,he just built a 113",130hp/120tq,me 95",ported heads,9.5:1,mik 42,thunderheader,1.7rocker arms,3.37 gearing and woods tw6 cam with 4*.Of course we raced,he blew me away(I just like the thrill) but it seamed like at 110mph(don't know what rpm was) that the cam was done(Don't get me wrong I could have buried the speedo) My dyno was 92hp/112tq.I guess my question is,do I need more lift or more duration,for a longer lasting cam?I still have a set of se211.

 

[cernunos]

Halloo. With that gearing, depending of course on the primary ratio, you were pulling around five grand I'd say, off hand. To pull hard up higher you are probably gonna need more than just more cam. Higher lift is only going to help if the heads can flow at that lift. Otherwise your just working the valvetrain that much harder. You say the cam is four degrees advanced?? You might just try setting it "straight up". In my experience you shift the torque curve up or down around 500 rpm with a four degree retard or advance. Plus, how heavy is the scooter? Taking some weight off always helps.

C.......

 

[torqueinc]

dyna/bagger ?

 

[secondchance]

Sorry,it's a 02 EG. And with the 1.7 rocker arms, I think my lift is around 540? I like the low end tq of the tw6 cause I ride 2up and in the hills alot more than freeway.So,if I pull the 4* gear out,my tq moves to the right ?HP also moves,cam comes on later? I use that 4*because I don't have the compression (10-10.5) that I have heard it likes.

 

[secondchance]

Is there a better cam,with 510 lift that can give me good low end,with longer legs.Just wondering?With the lower gearing,will that make up the low end tq if I go with a longer duration cam?

 

[torqueinc]

I do not think you will find a much better cam with .510 lift
If you have had some headwork done and want the torque to stay where it belongs you will need lift not more duration to improve on what you have.
Just my two nickels

 

[Totenkopf]

if it were me, I would leave the TW6, it's a good street cam. I would then pull out the 4* gear and put the straight up gear in... I then would pull the heads and do what is needed to get the compression up to 9.9 - 10:1 and then get a great retune of the motor. By the way, is that the long Thunderheader? If so, that pipe is not helping you. The original one is a great 2-1, not so with the long bagger one.

A 113" motor should pull away from you unless it isn't running like it should.

If you want to get some more insight into cams, there is a sticky at the top of the Twin Cam Engine Mods section that explains some things about bump sticks.

 

[secondchance]

I do have the longer thunderheader. Would I do better with a andrews 37,because I have less compression? And what about the andrews 48,would that work with my 95" set up?

 

[Totenkopf]

Would I do better with a andrews 37,because I have less compression? And what about the andrews 48,would that work with my 95" set up?

No on the 37, it needs the same compression as the TW6.

No experience with the 48, it's a relatively new cam. From what I saw it is a real early intake close. The TW6 with the right compression will be a very balanced power output.

I realize you may not like this but here is the right things to do.... Keep your existing setup but change your pipe to one that works, pull the heads and have them decked to get the right compression for the TW6 and then get it tuned by someone knowledgeable.

 

[sublime]

I do have the longer thunderheader. Would I do better with a andrews 37,because I have less compression? And what about the andrews 48,would that work with my 95" set up?

Sounds like you have a pretty sweet running bike already...

The cam alone isn't gonna do it for you... If you want the best you can do without doing MAJOR work to your bike (bottom end), this is what I'd do... You live right near B.C. Gerolamy's shop ( http://www.bcheads.com ), he is one of the best head porters in the country, have him do up your heads, get some 98" pistons, have your cylinders bored / honed and compression set to 10:1, pull the 4 degree gear from the cam, switch the pipe to a D&D fat cat, have a good tune done. Your bike will be night and day different..

The 113" will still smoke you though, at least it should..

If you wanna take him down you're gonna have to crack the bottom end to do it and keep your bikes touring manners... You could build a 120" mill that'd eat your buddy's 113 for breakfast.

 

[Fred1369]

I'm surprised no one has mentioned this: there's no replacement for displacement.
My builder, who was the best wrench and machinist I or you have ever known, before his untimely demise, thought the Andrews 37g was the best street cam. Not a race cam but the best for everyday city and highway use. However when he did my bike they were back ordered so he put in an S&S 510. I'm not complaining. T-man Performance polished and ported the heads. The big advantage of NOT having the fastest bike on the block is you still have a grin factor while using Regular gas. People are going to get tired paying for Premium.

 

[secondchance]

Wanted to do the 98"10.1,but was talked out of it,everyone said 3 more cube inches wouldn't be worth the $$.But I wanted to do it just for the compression.Oh well.I guess I will leave it alone,until I save more $$ to do the 98".Thanks everyone !!!!!!

 

[Don Dorfman]

Simple math and budget call
Do you have an extra 4k to make yours a 113?
If yes is it worth parting with spending the money, the opportunity cost, to beat your buddy?
If no use Totes plan

 

[thundertek]

Ok,here we go again,I know but bear with me,I just want to learn more about cams,lift,duration......Went riding with a friend,he just built a 113",130hp/120tq,me 95",ported heads,9.5:1,mik 42,thunderheader,1.7rocker arms,3.37 gearing and woods tw6 cam with 4*.Of course we raced,he blew me away(I just like the thrill) but it seamed like at 110mph(don't know what rpm was) that the cam was done(Don't get me wrong I could have buried the speedo) My dyno was 92hp/112tq.I guess my question is,do I need more lift or more duration,for a longer lasting cam?I still have a set of se211.

it is pretty simple. your buddies bike makes 130hp/120tq you need to make more and it is possible but not with a bolt in cam and it will need a killer set of heads you can im me and i will tell you what it takes

 

[sublime]

You can get close with that cam, some heads and a pipe.

You're looking at $300 for pistons, $120 for bore / hone, $1000 for heads, $700 for pipes and a few hundred for miscellaneous crap.


Honestly I'd save the money and enjoy what you have until it gets tired. Saving money all the while to move in to the big inch club.

If you really wanna smoke him bad come south a ways and I'll let you hop on my zx10r, he might have you for about ten feet while you roll on the throttle gently.


Sent from my Motorcycle iPhone app

 

[CowboyTutt]

Hi Second. I would have to agree that the one thing that has ALWAYS held you back every time with your build is the LOW COMPRESSION!!!
:dh: :beatdh: :duh2: :boom:

Those heads are only good for a mild camshaft that doesn't bleed off much compression. Until you resolve that issue your just not going to be happy!

Really the proper way to do this is pick your engine size an camshaft FIRST then build the rest of the motor around it, i.e. like valve sizes, head cc's, pistons, DYNAMIC compression ratio, all those things.

I've known some builders to make very impressive numbers with a 95 incher because of the shorter stroke and higher rev capability. But the motor has to be designed from the beginning as a SYSTEM.

That being said, being your bike is a Bagger, you really need all the cubic inches you can get in a milder state of tune that makes good low end TQ and good HP to 5500 rpm or so. So for that purpose your 95 incher probably isn't optimal.

Just sayin' my friend!

How much money you got??? :laugh:

-Tutt

 

[meultrahog]

Well, you could just do a leak down test, to make sure the rings and cylinders are healthy. If they are, just pull the heads, check deck height, depending on the deck height, send heads off to be milled for the compression your cam needs. If the pistons are down in the hole you can have the heads spin dropped. Put it back together with a set of .030 mls head gaskets and new rocker box gaskets. possible different pipe and a tune, away you go. My 2cents.:beer:

 

[secondchance]

Hey Tutt,was going to pm you and give you a heads up.lol So,it sounds like compression is what I am lacking. meultrahog;What do you mean spin drop? Do you mean not touch the cyclinders?

 

[CowboyTutt]

I'm glad you have a sense of humor Second! My rear tire is almost burnt toast and I'm leaving soon for Spring Break but maybe in mid to late April I'll come out your way for a ride and a beer after a new rear tire install! :woohoo:

-Tutt

 

[secondchance]

Great,be safe,don't get to crazy. A friend just gave me a brand new patriot 2-1 pipe,so as soon as I have time,I will put it on and see if it makes a difference.