thank you Freez, that was a great help..

Freez, hopefully PIASINI will get there on the ECU/rev limiter.....i'll pm you any good news..or any news on it..but results won't be happening until the New Year...but this all helps progress.

Richard

Nice first hand info Freez.

how fitting is this crank ? how its work without touch the head ? what is the logic ?

The Raptor +5mm Hot Cranks has a shorter conrod so it will not hit the head, it will raise the XT's compresion from 10:1 to approx 10.5:1.

Oh yes, how I could not think ? .... inverse logic my brain is stop..
Thank you my friend !!!

No problem mate, we all learn something new every day in life. Hot rod +5mm cranks are a straight bolt in crank on the Raptors. I did not know the answer until I did lots of research.

There are a few Raptor stroker cranks out there that use the standard length conrods to reduce the angles between the small end pin & big end pin. These cranks use an off set small end pin in the piston, so the small end pin is machined higher up to-wards the rings to allow for the extra stroke.

You can also get spacer plates for the big stroker Raptor cranks with longer cam chains.:eusa_doh:

http://cgi.ebay.com/ebaymotors/Raptor-700-CP-14-1-Stroker-Piston-Lightweight-102mm-_W0QQcmdZViewItemQQhashZitem33505cc04cQQitemZ22039 1587916QQptZMotorsQ5fATVQ5fPartsQ5fAccessories

http://cgi.ebay.com/ebaymotors/Yamaha-Raptor-12mm-Stroker-Crank-Crankshaft-Long-Rod-_W0QQcmdZViewItemQQhashZitem33512dbd9aQQitemZ22040 5284250QQptZMotorsQ5fATVQ5fPartsQ5fAccessories

Ok I understand this mate but when use a shorter conrod, how changing the compression.how the position of the cylinder and piston?
piston 5mm below from the cylinder ?

A +5mm Hot Rod stroker crankshafts big end pin is off set 2.5mm further out on the crank web, if you use the standard length conrod the piston would stick out of the cylinder by 2.5mm.

So Hot Rods made a shorter conrod when using a +5mm stroker crankshaft so the piston cames back to simula deck height of the standard piston, the length of the shorter conrod is not exactly 2.5mm shorter, by doing this it will raise the compression slightly, which is great you get a stroker crank that can run standard pistons with a slight increase in compression.

Hi Everyone this is me again,
I want to know about Stg2 hotcam,
I know about some tecnical specs about this cam..
original specs are :
Intake open BTDC : 25
Intake closed ABDC : 44
Intake Duration: 260.00 degrees
Ex.Open BBDC : 60
Ex.Closed ATDC : 20
Overlap time : 45
Exhaust Duration: 260.00 degrees

anyone check for this timing for Stg 2 Hotcam ??
and how these angles affect the operation of the engine.??

http://www.xt660.com/showthread.php?t=14736&page=3

I know that :) I see and read all differents
Just I want to see tecnical differents between oem with Stg2 cam,
then I ask before degrees.
For example I know Stg 2 cam exhaust duration is 243 degree oem cam 260 degree..

I have not degreed the standard XT660 cam. The dyno results speak for them selves, you can see where the torque & HP is delivered with before & after runs.

Yes I see them. yamaha gives standard degrees in service manual

Yes I am aware of the Yamaha spec, but they do not state at what lift they measured the degrees at so it is hard to compare the standard cam against other cams.

what ever mate I was just wonder how is timing what is the difference, how its work.Because I see power diagrams of standard and stg2 cam..you know
just wondering. :) thank you for all information.. If I have a time a day I will check the stg2 timing with degree wheel and share here :)