notch the cam for midrange torque?

[posthuman]

new here, just bought a 82' maxim w/ 11k on it, nice bike!

read someplace on this site about changing the torque peak by something called "notch the cam, move 5' " for midrange torque, off the line improvement.

I dont figure ill be doing much 100mph+ driving so this makes sence.

i've searched the site so sorry if I missed it,
can someone explain this in detail?

[mro]

Try a search "MAXIMAN"

he's doing some heavy duty mods to his bike, and more grunt at the lower end is one of em........



mro

btw
Welcome to XS land.
Newbe's should post a pic of there scooter.

Also "posthuman"???????
Guess that's better than "prehuman"

[prometheus578]

(I call the boss's kid "Proto-human". Same thing)

[79XS11F]

It's in this thread

http://www.xs11.com/forum/showthread.php?s=&threadid=10740

Rob

[trbig]

I have followed that thread myself... but didn't actually understand what you are notching on the cam and how you advance it 5 degrees.. Sorry. Does having a blonde wife excuse me?? lol. Another night banished to the couch for me.... *Sigh



Tod

[79XS11F]

The cam is not notched. It's the cam SPROCKET that gets notched so that its position can be rotated. So where the cam sprocket bolts go through the sprocket ... those 2 holes get notched or elongated so the valve timing can be altered before tightening the sprocket bolts
Rob

[posthuman]

thanks:

yes i'lll get around to posting a pic, when its done being cleaned up, it had been left sitting in the rain for a year before I found it.

thanks rob

as for picking at newbs nicknames:

http://en.wikipedia.org/wiki/Posthuman_%28Human_evolution%29

heh

[trbig]

I see said the blind man... So how do you know how far to elongate the holes to know where 5 degrees is going to be on the sprocket? Sounds like machinist work to me... I don't think my Makita drill would be quite accurate enough... lol Also... if you only advance the intake, does that cause slack in the chain between the cam sprockets? Seems like the exhaust sprocket would take up the slack and get advanced 5 degrees also??? *Scratching head...

Tod

[prometheus578]

"Hey, you slacker!"

There would be no extra slack in the chain. The sprockets would still be in the same relationship to each other, but the cam would be rotated 5 degrees on the sprocket.

[mro]

capabilities so radically exceed those of present humans

capabilities so radically exceed those of present humans

So................dats a "posthuman"


mro

Hopefully sometime soon they’ll evolve and catch up to XSive's

btw

as for picking at newbs nicknames:

been known to be a real pecker sometimes.......mean picker

[posthuman]

note that posthumans dont exist (yet), its speculatiive.

back on point:
it seems a machine shop would need to do this, so whats the best "bolt on" performance enhancement for torque, if any?

(besides the rider loosing 90 lbs of fat)

[mro]

1100's are pretty grunty for 25+ year old tech. Propery tuned and not too many miles on em and they go real well.

Most mods I've seen to make em more powerfull are pretty involved and the cost/benifit ratio doesn't seem to be too good.

78/79 cams will go in an 80/81 but have not yet played with 82's.
That being said, cams from 78/79 coupled with your larger valves might give a little more.


mro

[Pat Kelly]

I remember someone I worked and rode with raced Kawasaki 750's. They did a similar mod by just moving the sprocket on the cam chain 1 tooth. Seems like that would be about 5 degrees.
Loosen/remove the cam chain adjuster.Unbolt the sprocket from the cam. Slip the cahin off that sprocket. Loosely install the bolts. Rotate the cam about 1 tooth. Re-remove the cam sprocket. Reinstall the chain. Bolt the sprocket back on the cam. Check that the cam timeing is one tooth off from the other. Done.

I'm not going to do this with mine. Stock motor is plenty for me. I want more but will stick with stock(ish).

[trbig]

Anyone have any way of finding out just how many degrees one tooth would be? 360 degrees= 5 degrees 72 times. I am not around home right now, but I know the cam sprockets don't have 72 teeth. Not the sharpest pencil in the bunch, but one full tooth would seem to be way more than 5 degrees. Am I wrong? (Usually am... lol)

Tod

[posthuman]

gah
iIts an '81 not an '82, my bad

so a change in cams from a '81 to a '79 is a common mod.

iIteresting, I wonder what the exact difference is between them.