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In looking for some more power and torque, I'm totally confused on which way to go with engine mods on a injected bike.

1. Is the 95" kit really needed?

2. Could I just go with a set of cams to boost torque and HP?

3. How about cams and headwork?

4. How about cams with higher compression pistons?

I am not looking for the perverbial crotch rocket just alittle more zip and umph when I'm riding 2-up or just keeping up with the pack. Or in emergency situation I'd like the power to get out of the way or merge onto a expressway. The stealer will install a Stage II kit for 1350.00 but the reason I bought the bike was to do my own thing including working on it, although if they do the work they will keep the warrenty intact.
When I look at the charts in the catalog there isn't much difference between the big bore stage I and stage II kit.

Is it worth the difference?
 

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You're looking for more torque. How much do you want to spend? That is really the question.

My suggestion is to BB your jugs, keep compression to a max of 9.5:1, install a set of cams that will work with your combo, leave the heads alone for now.

The improvement will be substantial and reliable and it won't break the bank.
 

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Good suggestions from Cold Rider. I would also add that properly tuning an EFI bike is a bit more complicated that a carbed one. It is just about impossible to do correctly without putting it on a dyno (good one with a trained operator). Use of a PCIIIR or the new HD EFI tuner is also highly recommended. Again, more bucks though. It's too bad you're in NJ. Short Block Charlie (SBC) has a post on the TC88 engine forum about the "Scotsman hop-up" that his shop does in Arizona. Very good approach.
 

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OK so here is some engineering stuff to think about.

Horse Power (HP) = Torque(TQ) * RPM/5250.

It is that easy. Every chart you look at dyno -smino will show HP intersecting TQ at 5250 RPM. It ain't no coincidence. TQ exceeds HP on every curve until 5250. HP exceeds TQ above 5250. Except at RPM = zero then HP = TQ = 0. But you knew that!

So if yoy ride over 5250RPM then focus on HP. Say 5000 RPM and up

If you ride under 5250 RPM then focus on TQ. Say 2000-5000

The math ain't changed in 100 years.
 

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i would recomend a scottman hop up. install a 95kit/andrews tw44
cam/ deck heads .025/ cometic head gasket/ adjustable push-rods.
you have your choice a dfo or an efi tuner. if i had my choice an efi
tuner.i do these kits all the time with complete customer satisfaction.
short-block charlie
 

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Tsuter, your right! I believed you without checking my dyno charts(LOL), but....... they do intersect at 5250 . Sh$t, I knew that.
 

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IronButt
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One thing I did not see was A exhaust system. If you are going to spend the cash on the hop up's please don't waste the investement by bolting on a set of drag pipes. Looke to a good 2-1 system they will give you the msot gains. This may cause a riff but the bottom line is the 2-1 systems are producing the most gains. We just installed a Rehinhart system . I am going to dyno in the morning. They make claims to producemore hpand tq than most 2-1 pipes.
 

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HDWRENCH said:
We just installed a Rehinhart system . I am going to dyno in the morning.
Carb or EFI?
 

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harleyhog said:



Sorry guys, first time the Alcol..I'm DRUNK!! for a while.....
 

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HIPPO said:
That explains the tittz your avatar seems to be growing. :D
:eek:
 

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HDWRENCH said:
One thing I did not see was A exhaust system. If you are going to spend the cash on the hop up's please don't waste the investement by bolting on a set of drag pipes. Looke to a good 2-1 system they will give you the msot gains. This may cause a riff but the bottom line is the 2-1 systems are producing the most gains. We just installed a Rehinhart system . I am going to dyno in the morning. They make claims to producemore hpand tq than most 2-1 pipes.
What were your results like on the Rehinhart?
 
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