Introduction to Bigger Motors

Location
Ohio
I am getting a X scream 827-865 cc next. It seems like a no brainer to me. Bang for buck, stock stroke, lots of bores, killer builders! Lots of good details here though....nice posts!
 
Most Engines shops aren't going to post prices, Every motor package is different so its hard to give you #'s. Best thing is to call some engine builders & ask. I personally like Xscream & the after service I can't say enough about. Give Radney a call & you will be happy!. Me & my riding buddies all ride Xscream motor packages, motors just run & we never wrench on them!!!!

I got another Xscream motor in the oven now!

Last weekend at st aug.. it looked like a x-scream convention... A lot of brap...:afro:

"You said motors just run & we never wrench on them" Chuckie's install instructions..
1) install
2) align
3) ADJUST IDLE..
4) break in ...then beat it up...
 
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wsuwrhr

Purveyor of the Biggest Brapp
Does stroking a motor generally decrease the reliability?


To directly answer your question on reliability, the answer is no.

But to answer just what I THINK you are asking, the more stroke you add does increase wear on a total scale. Mostly wear on the pistons and not the crank necessarily. But you are talking engine life between "inspections" to be 100 hours of run time(or more).


Brian
 
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Location
dfw
Does stroking a motor generally decrease the reliability?

The wear factor is greater on almost everything. Most of the reliability problems wont be within the engine as long as the build and tune is correct. Many problems come from the extreme shaking common to all these long stroke twins. You will see a lot more chafing, cracking, and slipping with everything attached to the engine so good maintenance is required.
 

Aircraftsalz

Thrust built Dasa Power
Location
Off site
Last weekend at st aug.. it looked like a x-scream convention... A lot of brap..

That was cool last weekend, great time riding with you guys from Clearwater.

"You said motors just run & we never wrench on them" Chuckie's install instructions..
1) install
2) align
3) ADJUST IDLE..
4) break in ...then beat it up...

(4) I always seem to skip this step!


Does stroking a motor generally decrease the reliability?
I have a 6mil/860 stroker & love it. I got over 100+ gallons on it from March-July, pulled it apart & it looks like new. Set up right, it's just like a stocker!

Xscream = The real Deal!
 

Waternut

Customizing addict
Location
Macon, GA
I'll see what I can contribute to the questions...

Most people don't run power valves right now because that requires an aftermarket engine and they are pretty pricey compared to a stock engine. If you're familiar with cars, a power valve is like the two stroke version of Honda's VTEC.

There's been good talk about strokers but I think the initial starting knowledge that is needed is missing (as it makes perfect sense once known). A stock stroke 701 engine is 68mm. That is the measurement from the top of the piston stroke to the bottom of the piston stroke. A 4mm stroker would be 72mm. A stock kawi 750 engine has a stroke of 74mm so a 4mm stroker on that engine would be 78mm. The stroke between two different engines may not give any real correlation but increased stroke on the same engine generally gives more torque and therefore more power.

A sleeve is what you see when you look into your engines cylinder. Re-sleeving is typically done because the current has been damaged beyond repair. Some will resleeve for what's called a "big bore sleeve". That basically requires boring the cylinder after sleeve removal so that a larger aftermarket sleeve can be installed into an otherwise stock engine for more displacement and more power.

The purpose of reeds is control air flow into the engine. I can't explain that very well put if you search on google for "how do 2 strokes work", you should be able to find pictures and videos of how the reeds play a part.

If done properly, porting a stock engine shouldn't produce any real noticeable stress on the engine. Not all porting is created equal though, some produce low rpm power, others produce high rpm power, and some just destroy engines if done by someone who doesn't know what they're doing. It will give you some extra power though so it's worth looking into.
 
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