Launch RPM's...

[RedRider]

Approximately what RPM's should I be launching an '04 stage 1 1200 when racing, and how aggressive on clutch release? TIA, guys.

[stevo]

G'day Red

Somewhere in the 3000 - 4500 bracket.

You want to throw the clutch away to the take up point and then feather it from there...take quite a bit of practice to get it right.

If the bike bogs then try a higher RPM.
If it wheelies you've let out too much clutch


ou are looking to try and slip the clutch out so that the front wheel sita about a couple of inches off the ground thru first

[RedRider]

Thanks, Stevo. Sounds like good advice. You sound like a guy who's had quite a bit of "practice" doing it!

[stevo]

yeah....up near 500 passes on the sporty and probably nearly as many on other bikes over the years....been racin since 85..

There's a few more tricks too but ya need to handle the basics and work up from there....let me know when yu've had a few more passes under ya belt and what you think it's doin.

The gsxr1000 streetfighter in my current avatar (25/11/04) has only been down the strip at one meeting but it ran 10.8's and gettin quicker each pass

I'm aimin for 10's outa the sporty when it's rebuilt at 88"

[RedRider]

Hey Stevo, I know that this is getting off-topic, but what kind of horse power numbers to you think I would get with my '04 1200 (currently stage 1) if I had the heads ported, changed cams & left everything else alone?

[stevo]

G'day

What cams and who doin the headwork????? pretty open ended question.

How long is piece of string?????????

[RedRider]

Maybe I'm fishing for some advice here... I would consider Nallin or another reputable vendor to do the heads.... A mild cam size, perhaps one or two steps over the stock cam specs.

To give you a little background, I worked as an engine builder for a period of time and have experience hopping up cars & trucks, but I have never cracked the case on a bike engine and tinkered with it yet.

Drawing from my past working with V8's, I know that there is a tremendous amount of power to be gained by improving air flow in the heads. I also know that I don't want to go crazy on cam size because this bike is a daily driver, not a dedicated dragstrip bike.

What cam specs/part number do you recommend for this type of application?

It's tough being an oldbie in one respect and a newbie in another, know what I mean?

[stevo]

G'day Red

I've got an engine recon background in cars too.

Look at a sporty motor as a longstroke pushrod 2 valve V motor with a common plenum... big block without the other 6 cyls.

All the basics apply, just that those heads are better than most stock heads ya ever seen before.

I havn't played with the new '04's yet but I wouldn't go much bigger than an N4 for street use and with good headwork (and you have a good starting point too with the XB heads) and the rest of the set up to complement, then 100hp is achievable but optimistic, => 90 would be closer.

I think there is some new profile cams available for the '04's.

Have a talk to Nallins or HQ or tilleys or whoever ya thinking of doin ya head work.

Nallins make good HP and don't mind revs...HQ and Tilleys tend to be more torque and street friendly

[chopperdave]

Originally Posted by RedRider

Approximately what RPM's should I be launching an '04 stage 1 1200 when racing, and how aggressive on clutch release? TIA, guys.

hi,
i launch at 5500rpm and do a controled release as quick as poss front wheel comes up 3 to 4" and grab gears

--------------------------------------------------------------------------------
1994 harley
74 c.i.
dropped /chopped
59"wheelbase
belt drive
150 avon tire
s&s e carb
custom ram air
custom seat
custom fender
forward controls
thunder header
490lbs
best rt .504
107.99mph
60' 1.7 1.8
et 12.25 12.26
runs low 12's, no bar, rides to track at track and every where else , rain or shine

[Chuck]

[QUOTE=stevo]G'day Red

Somewhere in the 3000 - 4500 bracket.

You want to throw the clutch away to the take up point and then feather it from there...take quite a bit of practice to get it right.]



Do you power shift (don't let off gas) when going through the gears?