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Discussion Starter · #1 ·
is it worth it whats the hp gain also will it make hit rev limiter easier and rev faster????


thinking of adding a 5mm stroker worth to throw in a 5mm or go longer ???
 

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Clean 700 Raptor
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Motor build

Yes its worth adding the 5mil stroker crank, you should pick up 2 to 3 hp, but 5 to 6 more foot pounds of torque. Take a look at my signature and that setup puts out 69 hp and around 54 foot pounds of torque. I'm now chasing that 80 hp mark, should find out tomorrow on the dyno.
 

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Discussion Starter · #3 ·
Yes its worth adding the 5mil stroker crank, you should pick up 2 to 3 hp, but 5 to 6 more foot pounds of torque. Take a look at my signature and that setup puts out 69 hp and around 54 foot pounds of torque. I'm now chasing that 80 hp mark, should find out tomorrow on the dyno.
your build doesnt run on 91 oct right???? whats your elevation
 

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Big difference from the big 3, rev a lot faster. With the mods on my sig. it makes 63 HP 91 octane fuel 3000 ft . CP 11.5 and No port and polish.
 

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Discussion Starter · #6 ·
i see everyone has +3 tb is it worth doing with only 12:1 JE Piston hotcam3 and 5 mm stroker???

what will it do improve rev, throtlle response, hp gain by atleast 1 hp???
 

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Max replied to your PM. Keep in mind with the stroker its going to bump your compression a tad because of the SR setup. I'm all for reliability and still making good power which is why I recommended in your price quote PM the 11:1.
 

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Discussion Starter · #11 ·
ok I hate when this happens I get all different replies on wich the crank is worth getting on a stock head

hc3, 12:1, PnP with stock valves, for 750$ for around mid 60 hp

or

Hc3, 11:1, stroker 5mm crank, for 620$ for again 60 ish hp

so help plz lol Im not gonna put any other engine mods after
 

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welp ill put my opinin in the open...i love the 5mm cranks, but if it were me i would do the complete top end instead of the bottom end and a piece of a top end.

tech 11.5
ported head
hc3

what im lookin at also is if you get the crank you will spend 3-400 to get someone to install it unless your doing it yourself. if your not doing any more mods in the future i still like the head porting over the crank. but thats my .02. and if u ever decided to go any further you could upgrade to a 50/50 or add a tb to get some extra without ever splitting the cases
 

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I will throw my 2cents in. For reliability I would do a head package with a piston and leave your stroke and bore alone.

Lets look at how stroke effects your displacement vs. bore. When calculating displacement both numbers are used, but the bore number is squared. Because of that the increase of 5 millimeters in stroke is equal to about a 3 millimeter increase in bore. So if displacement is what you are looking for then a big-bore is a cheaper more effiecient way of increasing it. Keep in mind that altering the stroke of the crank and not correcting the rod length(spacer plate or custom piston required) effects the rod-ratio which in turn effects engine life and reliability. Why pull and split the cases to accomplish the same result as adding a simple big-bore kit...

Nate
Alba Racing
 

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Discussion Starter · #16 ·
well no its not cheaper a big bore is 600$ so around 800$ with cam and I get stroker piston and cam for 620$ also spliting the case is not a problem did that stuff all my life I repairs bike as a hobbie plus my dad is a licsence mechanic all I want is a bit more power to satified my needs not a drag machine I want 60 ish hp thats it
 

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Your time must be worth something... I have seen up to around 70 at the wheels with a head package and piston with a proper tune and still have 3-4 seasons of hard riding time on them without a hiccup. Like I said just my 2cents.

Nate
 

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Cola Crew
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+1 with Nate
Look I like my 770 alot but I had to do it. The stock rist pin pulled out of the stock piston and bent the rod... So to get to the #'s that you are looking for head,cam and piston is the way to go...
 

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Go with a CP piston

Hotcam stage 3 and a CP11 or tech 11.5 will result in around 8 hp gain

if the head is STOCK u will only gain 1 hp or so with the 5 mill but u will gain about 3 ft tq
The crank is well worth doing if u WANT or HAVE to split the cases and are doing the work yourself.

IMO the best and easiest Bang for the Buck after the Big 3 is CP PISTON, HOTCAMS STAGE 3, +3mm BORED THROTTLE BODY combination will add 10-12 hp if u are running duals,
 

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I will throw my 2cents in. For reliability I would do a head package with a piston and leave your stroke and bore alone.

Lets look at how stroke effects your displacement vs. bore. When calculating displacement both numbers are used, but the bore number is squared. Because of that the increase of 5 millimeters in stroke is equal to about a 3 millimeter increase in bore. So if displacement is what you are looking for then a big-bore is a cheaper more effiecient way of increasing it. Keep in mind that altering the stroke of the crank and not correcting the rod length(spacer plate or custom piston required) effects the rod-ratio which in turn effects engine life and reliability. Why pull and split the cases to accomplish the same result as adding a simple big-bore kit...

Nate
Alba Racing
Nate, I completely understand what your saying, but the +5 crankshaft is a solid performer. Your customers will love it, and if installed correctly their is no major reliability issues I'm aware of. There's a lot of +5 crankshaft Raptor's rolling around here maybe they can chime in and offer an opinion?
 
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