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Discussion Starter #1
Anybody built a high HP wild ass sportster? How do they respond to performance mods? What kits are available? How big can you go on a big bore kit.

Was kicking around the idea of doing a bare bones hot rod sporty just for fun. Something to embarass the crotch rocket crowd on a regular basis. They are cheap, plentyful and light.

Anybody got experiences or pics?
 

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I haven't seen your bird.
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Originally posted by Peacekeeper
How big can you go on a big bore kit?
I've wondered that myself. You hear all the time about people boring out their 883s to 1200s, but I've never actually heard anybody say how much bigger, if any, you can go than 1200.
 

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Discussion Starter #3
MadCity said:
I've wondered that myself. You hear all the time about people boring out their 883s to 1200s, but I've never actually heard anybody say how much bigger, if any, you can go than 1200.
I've found 1250 kits so far, but thats it.
 

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ive read about high hp sportys in a sportster performance handbook as large as 96 and 100 cubic inches but the reliability is extremely low not for daily use do your research
 

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How fast do you want to go???I just built one with a little over 11:1 compresison, andrews N8 cams, 1200 wiseco's and some Hillside head work...
That little beast sure does go. No dyno yes as i just finished it and its snowing here now..

There are a ton of options with strokers as well. Just depends on how fast you want to go. They are A LOT of fun and i have been thinking the same thing as you.
 

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Discussion Starter #7
TXCHOP said:
How fast do you want to go???I just built one with a little over 11:1 compresison, andrews N8 cams, 1200 wiseco's and some Hillside head work...
That little beast sure does go. No dyno yes as i just finished it and its snowing here now..

There are a ton of options with strokers as well. Just depends on how fast you want to go. They are A LOT of fun and i have been thinking the same thing as you.
Looking for a tire smokin bar hopper, just something to ride away the stress and exercise my mind. Would like to shut up a few crotch roket jocks too.
(son in law) Lookin for an obnoxious loud beast that is just for fun.
 

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That combo i just did will turn at least mid upper 80's hp and tq with a good pipe and tune. That will make the light sportster move pretty good. Oh and dont forget the adjustable ignition. There are plenty of other combos out there than can turn 100 hp without changing cranks.
 

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I have had 3 hi po sporty motors now. an 80 hp 1200 ,then an 88 inch zippers motor that did about 112 hp and similar tq....that was a wheelie machine...then I wanted something more and that got tough.I wanted a 10 second 1/4 mile street harley. Ended up with a nrhs motor with std heads and s&s cases that does 130 hp and with nitrous pulls 157 hp and over 130lbs of torque. They are both street ridden.


 

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I wanted the same thing for my showbike (just kind of turned out that way - its my daily rider) and hung out at the track at Sturgis to see what the guys were doing to their bikes. I also have a guy that races Sportsters here in town down there, so I got to watch him too.
The Sportster is the Harley race bike, and has been for 50 years.
From Jims, to NRHS, to a couple other companies this is a lot you can do to them to get them quicker.
What I found out is how much money do you have vs. reliabilty and power you want.
The kit I found that is the best bang for the buck is the Jims 100 horse kit for $3500. With jugs, pistons, cams ect. The whole nine yards, no guesswork as they already do the flow testing and everything.
Right now mine runs about 80/80 horse/torque. But if I had the money that is the kit I would get.
I do about 10k miles a year, so it has to be reliable. (My 06' Sporty is my bagger, show bike, and speed demon all in one!)
Good luck and have fun ridin.
 

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From Know Nothing To Sportster Expert In 2yrs!

Hey All,

Just joined this forum, I started with an 883XL almost two years ago. I now have a performance monster. Bikes not even broken in yet but here's the distillation of my two year quest for a monster sportster.

Best bikes to get top performance is an evo. You can buy 883's cheaper by $1000 to $2000 than a 1200cc bike depending where you live. Better to start with the 883 since your changing everything from the case up anyway - the money you save you can put into the top end.

The best approach if you don't have unlimited cash to burn on a project like this is do what Buell did - but - do it better! Yes you can make a stock sportster into a 100 + hp killer. Some guys get 110 - 120 and more but they have $10,000 in their bikes by then.

The recipie:

XB1200 heads (2004 and up Buell heads) ported if you got the extra stage 1 - $500 - stage 2 $800

Bore stock cylinders to 1203 stock bore to use stock Buell pistons & rings.

You can use the 04 and up wider finned cylinders - there are advantages.

Andrews N4 cams for low & middle grunt with nice top end. The more money and exotic your heads the higher lift cams you can use - you can have huge arm jerking roll on power (N2 N4 cams) or fly in the high rpm range with high lift cams. Depends on how your goning to ride it. N4 is the best choice by many experts advise. Best of both worlds.

Mikuni or Super G carb. Cant remeber if it's Super E,G, or what but almost everyone who hot rods a sportster uses a Mikuni for crisp response.

Dyna 200 programmable nose cone ignition
coupled to a DC5 single fire coil set.
Irredium plugs

Two into one exhaust - Supertrapp two into one seems to be one of the best inspite of more expensive units out there.

Pingel High flow fuel petcock - your gonna need this.

High Flow Air breather such as Screaming Eagle or the NRHS 3" wide one.

Without doing the heads (no porting or bigger valves) this is going to get you almost 85 - 90 hp at the back wheel.

An extra $500 to $800 dollars will get you into about 95 - possibly 100 hp at thje wheel.

If you go with stage two heads $800 plus higher lift cams and a lot of tunnig you can break 100hp at the wheel.

If money is no object then buy the S&S Hot kit (1550cc +) set up and then do the heads, add a Mikuni and you have a 120 Hp sportster. 1450 - 1550 cc is the biggest you can go using stock cases. Look into Mountain Motors by Axtell too same thing as an S&S Hot Kit but less complete unless you buy the entire motor turn key.

Long winded but I hope this helped. Study NRHS. Nali Racing Head Service. They are the undisputed guru's of sportster performance.

I bought everything on ebay and with heads, carb, cams, ignition, coils and petcock I think I was not far over $1300 - $1400 then cylinder boring. My assembly was done by Brain of Brain's Bike shop - a well know local top flight engine builder and Harley mechanic.

So for my hot stock 85- 90 hp bike I have less than $2000 in the performance build.

Best regards,

56r
 

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Mine was done years ago when Buell and Thunderstorm were most likely the big deal at the time for HP Parts.

Now I understand the new XB 9 or 12 heads are better.

This is a list of stuff that went into mine to produce 80 plus HP at the rear on a dyno.

Buell 1200 Cylinders
Buell 10.5:1 pistons
Buell Thunderstorm Heads
Screaming Eagle cams
Screaming Eagle Ignition and coil
Screaming Eagle A/C with K&N Lifetime Filter
Screaming Eagle jet kit
Vance & Hines 2 into 1 Pro Pipe
Progressive shocks to keep the front tire on the ground

Mine started out as a 883 and still appears that way today :whistle:






Karsten
 

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Looking for a tire smokin bar hopper, just something to ride away the stress and exercise my mind. Would like to shut up a few crotch roket jocks too.
These are all good ideas but if you are looking to smoke a few crotch rockets, you may still have a way to go. It's just hard to compete with a 400 lb bike with 160 plus HP out of the box. The mods to your sporty would be more expensive then a used ricer. You need to decide if you want to go super fast or if you want to ride a Sporty.

I bought a totally chromed out 2004 1200 R for $7,000, I installed SE Heads that had been cleaned up a bit, N4 Cams, HSR-42 Carb, Samson Caliber exhaust and Dyna ignition and wires. It nets me close to 90HP. Now I am broke, have a $10k '04 Sportster and it still isn't fast enough. What next. I'm thinking Sporty for riding, Sport bike for flying. :beatdh:
 

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Sporties are very capable of hurting a *** bike. My 93 with n4 cams super e and kb pistons would hurt 600's all day. From light to light it's hard for the average *** bike and rider to keep up with a sporty, especially if they don't know how to lunch it. That 93 would scoot for a basically stock 1200. It even had garbage drag pipes. Bike was clocked at 136 Mph and it was still pulling hard. Sporties are mechanically superior to any big twin, and will obviously build power the same way. You can still get a respectable amount of HP but remember Tq is what you really want. Stroke=Tq, Bore and Rpm=Hp. If you run the biggest bore and stock stroke you can with good heads, cams and compression, you will build lots of power. Stroking it also will give you all the TQ you want but at the sacrifice of piston speed and crank case pressure. Oil leaks WILL appear and you will rebuild the top end more often. The downside to the boring the cases for the biggest possible bore is lose of strengh. It's all about the money you have. I would like to see a sporty with a 3in stroke and a 4in bore! That would be very interesting........especially in a buell frame.:whistle:
 

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These are all good ideas but if you are looking to smoke a few crotch rockets, you may still have a way to go. It's just hard to compete with a 400 lb bike with 160 plus HP out of the box. The mods to your sporty would be more expensive then a used ricer. You need to decide if you want to go super fast or if you want to ride a Sporty.

I bought a totally chromed out 2004 1200 R for $7,000, I installed SE Heads that had been cleaned up a bit, N4 Cams, HSR-42 Carb, Samson Caliber exhaust and Dyna ignition and wires. It nets me close to 90HP. Now I am broke, have a $10k '04 Sportster and it still isn't fast enough. What next. I'm thinking Sporty for riding, Sport bike for flying. :beatdh:
I couldn't agree with you more
 

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I did the NRHS 1250 kit with stage 2 heads and new cams about 2 yrs ago.

It was the worst upgrade that I did to my 04 883.

It uses a quart of oil every 500 miles.

There were several others with the same problem, with nrhs.
 

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yes it was a problem with the ring wich has since been taken care of and issues delt with. if yours isnt taken care of then call dan at nrhs and talk to him
 

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;!pstwhore
I did the NRHS 1250 kit with stage 2 heads and new cams about 2 yrs ago.

It was the worst upgrade that I did to my 04 883.

It uses a quart of oil every 500 miles.

There were several others with the same problem, with nrhs.
My stock 1200N uses about a quart between changes. Is this normal? I change it every 2500-3000 miles.
 
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