i allready have a 105mm bore with a 12.1 piston, stock stroke, which makes my DS a 719cc. look below for everything i have in my DS. my question is.. do i really need to stroke it? how much hp will i gain from it? about how much do i have now? and how much will it cost to stroke it now that i have everything else but a stroker? is it reliable? i mainly drag race my DS. i've beat so many raptors i lost count [img]i/expressions/face-icon-small-happy.gif[/img] i've never ever lost to a raptor or any honda and i've beat every banshee i've raced so far...about 8 so far[img]i/expressions/face-icon-small-cool.gif[/img] what about bigger cams? i have nos but have never needed it so far. thanks for the help guys !
ohh yea....is anyone from southern La. ? i never see anyone on here from La.? later

 

Get your bike dyno'ed and let us know what kinda HP you're making- anything else is pure speculation. Did you bore the stock cylinder out? or is it an aftermarket cylinder?- how long ago? no problems todate ? Is this a piston from CT?
What kind of head gasket are you using?
Only you know if you "need" to stroke it, sounds like it's a pretty quick bike as it is. Maybe Dual carbs might be an option. Stroking will produce more torque , how much is hard to say...

 

i would love to dyno it and see what it makes. but i dont know of any dynos around here. the motor is only 2 months old. it was my friends bike, i had a 99 banshee. he had it apart and being built for 4 months. he spent a total of 5700. on everything. he sent the head and intake to COPE racing to get ported . why? i dont know? they do mainly pro stock motorcycle engines. anyway when he got it all back he rode it once. i was very impressed with it. he spanked me on my big bore banshee with pipes and alot more. anyway i got lucky and he need money so i bought it from him[img]i/expressions/face-icon-small-happy.gif[/img] and sold my banshee
they had to bore the jug for the new liner to go with the 105mm piston. i askes him why he didnt send it to knutz and he said he never heard of him.... he doesnt have a computer....so i guess thats why he sent it to cope.

 

Sounds like I wouldnt be worth taking the motor apart again. It is hard enough to get the head to seal as it. Where did you get your piston from? What NOS jets are you running?

 

Give it a 87mm stroke, and make it close to a 760cc [img]i/expressions/face-icon-small-happy.gif[/img]
The stock jug is a nicasil coating,did they put a steel sleeve in it?
Jeff

 

im running a nos kit with 20n 22f jets. it felt very lazy with 18n 22f so i put 20n in and it hits hard. i sprayed it 8 times so far with no problems. i will find out about the sleeve and where he got the piston from and post it tomorrow

 

I also didnt know that web made a cam for the ds.

 

Thats were Team Alba gets there cams from also!WEB-CAMS

 

http://www.webcaminc.com/bombardier-atv.html

I wouldn't bother with the stroker at this point - more stress on the bottom end.

 

At this point, stroking it would not be extremely cost effective. In order to stroke it, you would have to replace the rod with a shorter one[and that causes more stress on the sides of the cylinder] or replace the piston with one that has a higher pin location.

I'm very curious about who it is that did the cylinder, and how they did it. I wonder if it's bored and nicasiled, or if a sleave was installed[since it had no sleave to start with, that doesn't sound easy]. I'm also curious about the head gasket.

Right now, your cams specs seam rather conservative, but not having built the motor myself, I don't know if you can go bigger. The springs you currently run may not handle more aggresive cams, and you may not have the piston clearance for higher lift. With that much displacement, and the large valves, my guess is that the carb is holding you back right now. Either set up duals, or wait to see if my experiment works out. Either way, I think that will be your next big power gain.

Others are right though, there is know way to know if you would gain or not unless we know what your starting with. In theory, you would gain torque and HP, but that's just theory.

I guess your friend doesn't read Dirt Wheels, does he? The feature was done on our 760 over 6 months ago. It could have saved him some money and you would have both the bore and stroke, along with oil and cooling mods. I'm not trying to be a smart @$$, I guess I just didn't market well enough. I now have a regular ad running in ATV Sport, but it's just a small one[all I can afford].