Ok, so last night I couldn't sleep (too much on my mind) and so I got out of bed at 10pm and worked diligently in my garage until 1:30am...result is that I got the motor out of my 2002 P650 (this motor is being sold to "Steve-O" from another forum in case you are wondering) and its now sitting on my garage floor on a piece of plywood. Quite a site to see...two P650 motors (fully functional) sitting side by side on my garage floor...its a thing of beauty I tellz ya! hehe

HERE'S MY QUESTION:
Before I reinstall my other P650 motor (from my 2003 quad that I'm now parting out) into my 2002 P650 quad that I'm keeping, what should I do to the motor as far as maintenance and/or a cheap upgrade? I was planning on adjusting the valves for sure (can't get much easier than when the motor is removed from the quad). Any other maintenance items I should do while the motor is removed?

How about cheap motor upgrades while I have the motor removed? I already have v-force cams in this motor, so I can't seem to justify spending the $$$ for different cams right now for this 2002 P650. I looked into getting the heads ported a while back, but at $500 to $600 to do both heads... its just a little more $$$ than I want to spend right now (same goes for a BBK, etc.). Any thoughts?

Happy trails...[img]i/expressions/face-icon-small-smile.gif[/img]

 

Wiseco High compression piston!! Cut tube leading from oil pan to air box inside crankcase!! Check cam chain tensioner for excess wair!!, Check threads for cam chain tensioner ( tensioner is stainless and casting is aluminum spring exerts extreme pressure on threads sometimes threads are pulled out of casting )!! Do a leak down test before installation!! Pull head to check for excess carbon on piston and valves or use a mechanics scope to peer through spark plug hole!! Replace all gaskets much easier to do it now, lol. That is just a few things give me a little longer and I can come up with more!!

 

Alltoys,
Thanx for the great ideas! How do I do the leak-down test? Isn't that where I screw some kind of compression gauge into the spark plug hole and then turn over the motor to TDC and then check the guage for compression? Is the purpose of this test to check the condition of the rings or some other part?

Happy trails...[img]i/expressions/face-icon-small-smile.gif[/img]

 

Mikey,
Absolutely!!!

 

Alltoys,
I took your advice and ordered some Wiseco 80mm (stock bore size) 11:1 pistons today. Now I can't wait to install them and see how it performs.

Happy trails...[img]i/expressions/face-icon-small-smile.gif[/img]

 

mickey,
how much were those pistons. I looked on their web site but couldn't find them. also if the motor is out and your puttin in pistons save up a little and get it ported. so far I don't have either but I will and I look forward to it.

 

FASTFATBOY,
Look at the online Wiseco catelog for Kawaski Motorcyle pistons and you will find it at the bottom of "page 48" (actually, its like page 9 of 13 pages in the pdf format). The 80mm (stock bore) 11:1 pistons for the P650 are p/n 4782M08000. These list for about $113 each (price includes new piston rings, snap rings, etc.)...but I got them much cheaper (actual dealer cost plus shipping) from a buddy who is a part owner of a MC/ATV shop. They also sell larger bore pistons for the P650 (example, 82mm pistons), but I didn't want to mess with boring out my cylinders...I'm just looking for a cheap and easy upgrade for my P650 motor...I think these hi comp pistons will work nicely with my stock V-twin cams (altho some radical cams with more lift and duration would be even better).

I looked at getting the heads ported and polished about a year ago or less and found that most reputable engine builders were charging $500 to $600 to do both heads on the P650...that's a little more $$ than I want to spend on my 2002 P650, so I'm going to pass for now.

PS - Have you considered XC racing with you Prairie? They have a local TX series that I race in called the ATVCCS and its a ton of fun...many of these XC races are in deep east TX not far from you. I race in their utility B class...its a LOT of fun! Go to www.atvccs.com for more info or send me a PM on here.

Happy trails...[img]i/expressions/face-icon-small-smile.gif[/img]

 

Mikey,
With those pistons you can shave off 0.040 inchs off the head increasing the ratio somewhat and still not affecting the V - Force cams. You will however have to retime the cams as this moves the chain on the cams.

 

While your brain is thinking of engine mods and the engine is sitting on the floor,,,,,,, now would be a good time to gusset that frame before it starts cracking!

 

Alltoys,
Thanx for the tip on shaving the head. Actually, I don't want to go much higher compression than 11:1 b/c I don't want to mess with race gas (can't afford it). Also, I'm pretty sure I don't want to mess with adjusting the cam timing/timing chain any more than I have to with my limited mechanical skills and tools.

PW,
Thanx for the tip...that's a good idea! Its too bad I'm not a welder or I'd do it myself. I'm guessing that the most critical spots to gusset are the front shock towers. What other parts need to be strengthened?

happy trails...[img]i/expressions/face-icon-small-smile.gif[/img]