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Author Topic: +5 Stroker Crank ?  (Read 803 times)

Offline MO RAPTOR 700

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+5 Stroker Crank ?
« on: April 07, 2010, 05:47:07 PM »
My mods are listed below. Its a stock stroke and bore. If I where to add a +5 crank what kinda HP gains would I possible expect to see? Thanks
2007 Raptor 700SE    Black/Orange
Barker In frame Duals, TRF intake, PCV, 11:5.1 CP Tech Piston, HCIII Cam, Ported Head (TRF), KDS +3 TB, Dynatek Programmable Ign.
15 tooth front sprocket
HID Lighting
Pro-Armor nerf bars
A-Arms skid plates

Offline Krandall

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Re: +5 Stroker Crank ?
« Reply #1 on: April 07, 2010, 07:15:26 PM »
Per talking w/ Alkire, Gunz, preddy etc etc etc..... There isn't that much of HP gains but TQ gains is where the stroker shines!


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Offline preddy08

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Re: +5 Stroker Crank ?
« Reply #2 on: April 07, 2010, 07:22:55 PM »
If I remember right KBR did a back to back dyno of a hot rod +5 and got 6hp and 8ft lbs of torque.
Just a little 81hp trail bike.


Offline Spartan

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Re: +5 Stroker Crank ?
« Reply #3 on: April 08, 2010, 12:33:22 AM »
If I remember right KBR did a back to back dyno of a hot rod +5 and got 6hp and 8ft lbs of torque.

So it's a static 6 hp and 8ft lbs of torque no matter what kind of top end work was done? No doubting or calling anyone out, I am just wondering if the bottom end makes all its own power so it's always the same no matter what happens up top...Any way you can get the rest of the specs of what they dynoed? Anyone else have a sheet for a built top end to stroker addon in power difference?

Again, this is just personal interest...It gives me an idea on what my build is doing for me also.

Offline 1badazz_700r

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Re: +5 Stroker Crank ?
« Reply #4 on: April 08, 2010, 09:58:31 AM »
I had a stockbore with a 12:1 cp, when i first put my +5 hotrods in. All i can say is WOW!! up to that point nothing i had changed made that much of a difference. way more torque and it reved alot faster. The stroker crank if i remember correctly from talking with troy also up's the compression by about .7. So if your running 12:1 it would bump that up closer to 13:1 :thumbs:

Just a little 778
105.5 WK cylinder CP 11:1
hotrods +5 crank
racersedge +2 head,with webb4
54mmTB with custom intake
sparks X-6exhaust
PC5/w autotune
dynatek programmable
slingshot lockup
+3 stock swingarm
hiper dual beadlocks/w gncc holeshots
flexx bars,burgard+2stem/w antivibe
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Offline Dales396LT4

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Re: +5 Stroker Crank ?
« Reply #5 on: April 08, 2010, 02:01:20 PM »
I think it's the 105mm Bore that upped c/r. The +5 crank and 105mm Bore will only get better with more air flow. I will tell you this a +5 crank and 105 Bore =770 most make 68-79hp and 55-65tq and it's a great Ride.

Offline Colorado700R

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Re: +5 Stroker Crank ?
« Reply #6 on: April 08, 2010, 02:16:19 PM »
I think it's the 105mm Bore that upped c/r. The +5 crank and 105mm Bore will only get better with more air flow. I will tell you this a +5 crank and 105 Bore =770 most make 68-79hp and 55-65tq and it's a great Ride.

It's hard to account for a single part in these equations.  The +5 will provide significant power increases (TQ and HP) but the overall increase is going to be determined by the sum of all the components.  

1. I.E. Cam selection with higher compression will be an important factor.
2. a customizable ignition curve
3. Big bore exhaust vs standard

there are more than a few 770's out there pushing mid-upper 80's or better.  And widdle 727 strokers pushing high 70's ;)
« Last Edit: April 08, 2010, 02:19:17 PM by Colorado700R »

Offline 1badazz_700r

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Re: +5 Stroker Crank ?
« Reply #7 on: April 09, 2010, 09:30:57 AM »
I think it's the 105mm Bore that upped c/r. The +5 crank and 105mm Bore will only get better with more air flow. I will tell you this a +5 crank and 105 Bore =770 most make 68-79hp and 55-65tq and it's a great Ride.
just boring a cylinder to 105 does not change compression ration. The piston selection will change compression.However troywcc,jon at racersedge and a few others have said that a +5 hotrods ups the compression around .7 points :thumbs:

Just a little 778
105.5 WK cylinder CP 11:1
hotrods +5 crank
racersedge +2 head,with webb4
54mmTB with custom intake
sparks X-6exhaust
PC5/w autotune
dynatek programmable
slingshot lockup
+3 stock swingarm
hiper dual beadlocks/w gncc holeshots
flexx bars,burgard+2stem/w antivibe
ASV's
odi's