Write-up of my FST 800 BBK Installation by Mikeyboy_esq ***

[part 1 of 2]

As some of you may know, I have been planning to upgrade my '04 Twin Peaks 700 to the FST 800 for a year (ever since I bought this quad). Well, I'm very excited to report that I finally did it!!! Below is my review of the installation process that I went thru to install the FST 800 BBK and VFJ Clutches including a link to about 50 pics of the entire process (tear down of the quad / motor & then re-assembly of motor / quad). Just thought some of you thinking about doing a BBK would be interested to see what all is involved in this process.

*** In case some of you are wondering why I didn't post about my BBK installation until now, I was keeping it a secret so that my local XC competitors would not know about it until we after we raced yesterday. I think I surprised a few folks in the holeshot!


MY UPGRADES:
I installed the FST 800 BBK with Stage 2 cams. No head work (b/c not in my budget). I also installed VFJ Stage 3 primary with spider mod and VFJ lightened secondary clutch. Instead of installing the YFZ Catch Can (I couldn't find a good place to fit this bulky little box without making the plastic fender piece stick out), I installed an air/water separator for an air compressor (I used this part on my old P650 motor with Wiseco pistons and hotcams and it worked good). So far, everything seems to be working good except for the air/water separator...(I'm getting oil in the airbox)...so if I can't make the right adjustments on this part soon, I'll install the YFZ Catch Can.


THE PROCESS:
It took me 4 weeks from start to finish. Could have completed it sooner had it not been for work and family commitments! The top-end of my motor was only gone for 9 days of this 4 week time frame (a BIG thanx goes to Mickey for a FAST turn-around!). I kept track of my time in the garage... I spent a grand total of 45 hours on the entire project (not including time to run to local atv shop/Lowes for supplies). I know, I'm slow!!! I like to take my time and double check everything! I'm **** retentive like that...lol The break down of this time was 11 hours tear-down and motor disassembly, 12.5 hours of motor re-assembly and 21.5 hours of parts clean-up and re-assembly of the quad.


THE PICS:
Go to the 2 photo albums labelled TEAR DOWN OF TWIN PEAKS 700 and FST 800 BBK PROJECT at http://s122.photobucket.com/albums/o273/Mikeyboy_esq/


PERFORMANCE RESULTS:
I've only logged in 91 miles on my quad since I put it all together about a week ago, but so far I'm happy with how fast it runs. A few of the highlights I've noticed from this BBK motor are:

1) will lift the front end off the ground if I stab the throttle at 10 mph on pavement (sometimes a little wheelie and sometimes a huge wheelie where I have to let off the throttle);
2) top-speed in approx. 600 ft. of pasture improved from 65 mph to 70 mph on the speedo (nice gain!!);
3) beat a Can-Am Renegade 800 in a 300 ft. holeshot in my local XC race yesterday! (I'll post a separate thread with my race write-up).

Most of the improvement seems to be faster acceleration in the mid-range and top-speed. The power on take-off seems very similar to before the BBK (except that I get a little more tire-spin on loose surfaces). The improved acceleration is most noticeable from about about 10 mph to top-speed. The first few times I rode it, I was not blown away with the power like I imagined it might feel (I never rode a BBK quad before, so wasn't sure what to expect). I was expecting an explosive throttle-response that was almost difficult to control, but I found my BBK motor is not as hard hitting as I was expecting...in fact, its quit smooth and very controllable in the woods. In retro-spect, I'm much better off with smooth throttle response b/c the quad would not be woods friendly (and XC race friendly) if it was much more hard-hitting than it currently is.


FUTURE UPGRADES:
I already have a set of 36mm carbs and a custom, lightened flywheel that I plan to install this summer. I hope to see some noticeable power gains over my current set-up, but I'm not sure yet if the 36mm carbs will make my motor too touchy/too much throttle response for tight woods racing. If so, I can always go back to the stock carbs. I would gladly do these upgrades now, but I'm in the middle of my local XC season and can't afford to miss any more races.

To Be Continued...

 

[part 2 of 2]


TOOLS & SUPPLIES NEEDED:
A pair of OEM Cylinder Base Gaskets, Service Manual, a set of metric wrenches, a metric socket/ratchet set, screwdrivers, vice, lock-tite, silicone or permatex liquid gasket, engine assembly lube, motor oil, oil filter, coolant, tape and a writing pen. I made a home-made sled to pull the motor around my garage floor. This motor ?sled? is not necessary, but it comes in very handy if you don?t have another person to help you carry the motor. While it?s not necessary, I found it very helpful to refer to an old write-up about installing stock V-force cams in a P700 as written by DirtyWhiteBoy in July 2004 (I think this write-up is still available under the Prairie Tech Tips on Nyroc?s website).


PART 1 - DISASSEMBLY

A. Time: It took me a total of 11 hours to clean the quad, remove the motor and disassemble the top-ends to be mailed to FST.

B. Steps:
1) Clean the quad.
2) Remove all fenders and clean the quad again (pressure washer).
3) Drain motor oil and coolant (keep old oil filter on the motor to protect the threaded piece of the motor during the removal and installation of the motor).
4) Remove exhaust, airbox, carbs, both clutches, front drive shaft, motor mount bolts, etc.
5) Disconnect all wires going to the motor, tape them up and mark them so you know where to reconnect them.
6) Lift motor and pull forward to disconnect the rear drive shaft. Then turn the motor sideways and pull it out of the LEFT SIDE of the frame. Once out of the frame, I placed the motor on a small sheet of plywood (with rope handles) that was sitting on the floor next to the quad. I used this ?sled? to slide the motor around in my garage (I worked off the floor b/c I don?t have a workbench!).
7) Remove Cam Timing Inspection Plug on the side of the motor to view the TDC marks on the flywheel.
8) Remove the pull starter to expose the center bolt underneath it. By turning this center bolt (with a ratchet and socket), you can rotate the crankshaft to the TDC marks for the Front Cylinder (pulled spark plug out to confirm it was TDC on the front cylinder). Using the same center bolt, I then turned the crank 270 degrees counterclockwise to the TDC marks for the rear cylinder.
9) I removed the rear cam chain tensioner, rear rocker arm cover, rear cam, rear head, rear cylinder and rear piston.
10) Turned the center bolt 270 degrees clockwise (or 90 degrees counterclockwise) to the TDC marks for the front cylinder.
11) I removed the front cam chain tensioner, front rocker arm cover, front cam, front head, front cylinder and front piston.
12) I packaged up both top-ends (not including the pistons) and shipped it to FST. NOTE: I paid FST to have the new sleeves pressed into the cylinders, drilled and tapped the rear head for the yfz catch can mod, and installed the heavy duty valve springs. Because my Twin Peaks is a 2004 model, FST also did the rocker arm shaft mod (which eliminates the bolts holding the rocker arm shaft in place).


PART 2 - RE-ASSEMBLY

A. Time:
1) It took me 12.5 hours to re-assemble the motor after I got the BBK parts in the mail from FST.
2) It took me an additional 21.5 hours to install the motor, yfz catch can, fenders, etc.

B. Steps:
1) Wash the cylinders with soap and warm water?apply motor oil to cylinders to prevent rust. Wipe the inside of the cylinders with a clean paper towel to see if any grit comes off. It if does, wipe down the cylinder and re-apply oil?repeat until you can wipe with a paper towel and no grit comes off.
2) Wash the pistons, dry them and apply assembly lube to the groves on the sides of the pistons where the rings go.
3) Insert TOP RING into one of the Cylinders and measure the ring gap with a feeler gauge. If not within spec, file the opening of the ring to widen the gap. The proper ring gap for the top ring and second ring is .014 to .018 inches. There is no need to check the gap on the oil rings. Do the same for the other rings using the other Cylinder. Make sure to keep the rings and cylinders matched up for installation.
4) Install the rings into the grooves in the sides of the pistons. The Light Brown Ring is the TOP RING. Thick Black Ring is the SECOND RING (a.k.a. the scraper). The OIL RING is made of up of 2 thin black rings that sandwich a wavy shaped ring in the middle. Be sure to position the GAPS in the rings according to instructions that come with the rings. The side of the ring with NUMBERS should faces up for the TOP RING and SECOND RING. There is no top-side on the oil rings.
5) Turn the center bolt (under the pull starter) to the TDC marks for the Rear Cylinder.
6) Insert one circlip into a FST piston and leave the other circlip off for now. Apply assembly lube to the metal tubing that attaches the piston to the rod. Insert the tubing into the piston and attach it to the REAR rod. Make sure the mark (dot) on top of the piston is facing the front of the motor. Insert the other circlip and check to make sure the piston rotates freely on the rod.
7) Install a new cylinder base gasket on top of the lower end of the motor for the rear cylinder.
8) Apply motor oil liberally to the outside of the piston and inside the rear cylinder. Squeeze the piston rings together and slowly push the bottom of the cylinder down over the piston until the piston is completely inside the cylinder. Bolt the cylinder down to spec (there is only 3 bolts).
8) Install a new head gasket.
9) Install the rear head and bolt it down to spec (there are 4 large bolts to tighten first, then 1 smaller bolt to tighten last).
10) Bolt a cam sprocket/decomp mechanism to the rear cam. Use Lock-tite on the cam sprocket bolts and torque down to spec. NOTE: You will need a vice to hold the cams while you tighten the cam sprocket bolts to spec.
11) Apply assembly lube to the rear cam (the rear cam has a groove on it/the front cam does not have this groove). Install the rear cam into the rear head with the arrow on the side of the cam sprocket pointing straight up (away from the motor). Take your time to get the cam chain over the cam sprocket.
12) Clean off old silicone from rocker arm cover. Apply fresh silicone (or permatex liquid gasket) all around the rocker arm cover and smooth it out with your finger. Re-install rocker arm cover to the rear head and torque to spec.
13) Rotate the center bolt (to turn the crankshaft) to the TDC marks for the front cylinder.
14) Repeat steps 6 thru 12 above for installation of the FRONT piston, cylinder, head, cam and rocker arm cover. Make sure the mark (dot) on top of the front piston faces the front of the motor.
15) Insert both cam chain tensioners and torque down to spec. NOTE: Before installing each tensioner, you must first unscrew the center bolt, remove the washer, spring and pin underneath the center bolt and then ?reset? the tensioner according to the service manual.
16) Making sure the piston is at TDC, adjust the valves for one head. I used .004 inches for the intake valves and .006 inches for the exhaust valves. Then rotate the crank to TDC for the other head and adjust the valves for that head.
17) Re-install the motor into the frame and put the quad back together.
18) Install the YFZ catch can and connect the hoses.
19) Fill engine with motor oil and coolant. Install new oil filter.
20) Break-in procedure. I was told to run the motor for 10 to 15 minutes at a time at varying rpms (not WOT). Then let the motor cool down completely and repeat this about 6 times. Then let her rip!

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