Alkire193 XC Build *Updated 8-16-2011*

[Gunz]

Your choice of intake and TB size will determine your RPM range the most, but a big cam with with a longer duration like the web 4 will help maximize on that range.
the tq of my bike makes me oversteer badly on corner exit.

That's not torque you goof, that's from lack of better suspension and tires...... CRIPES

[Colorado700R]

Your choice of intake and TB size will determine your RPM range the most, but a big cam with with a longer duration like the web 4 will help maximize on that range.
the tq of my bike makes me oversteer badly on corner exit.

That's not torque you goof, that's from lack of better suspension and tires...... CRIPES

I've tried almost every tire on the market now. The HS GNCCs are by far the best for me. Suspension on the rear of atv's is not like cars. The atv rear is designed more to handle air time and the subsequent landing, whoops impact, ect. vice maintaining traction in corners. Not much can be done there with a solid axle anyway.

[Gunz]

Your choice of intake and TB size will determine your RPM range the most, but a big cam with with a longer duration like the web 4 will help maximize on that range.
the tq of my bike makes me oversteer badly on corner exit.

That's not torque you goof, that's from lack of better suspension and tires...... CRIPES

I've tried almost every tire on the market now. The HS GNCCs are by far the best for me. Suspension on the rear of atv's is not like cars. The atv rear is designed more to handle air time and the subsequent landing vice maintaining traction in corners. Not much can be done there with a solid axle anyway.

There rear shock has more control then you think. I agree, GNCC's or RazR's are superior. Sounds like somebody needs a new suspension and his name rhymes with Lolorado700r..

[Alkire193]

I go on camera for 90 minutes and return to this. 

I agree with Gunz. The 15/36 that I had and you have is not a great gearing for the woods. However it doesnt cause the oversteer effect. Thats camber, tire pressure and suspension. Unless i'm misunderstanding what you are saying.

What I found on the 15/36 set up is that coming out of a corner I had to wait for the power arrive. If I could maintain mid 3rd gear on the trails I had a lot of fun, but if I had to climb or downshift I wasn't getting anywhere out of corners fast. I also noticed this lug on the MX track when I come out of corners with slower acceleration as the smaller 450's. Once I hit the mid range I was untouchable.

Krandall - Is the X2 installed on the atv I timed at St. Anthony's? I felt that low end, is was nice but I didn't get a feel for it because I had to return to the trailer. It did feel really good.

Colorado - The only reason I don't stick to the 770 (I agree with you about it being enough) is because now that I have the means, I don't want to come home and find that I need even more and the motor has to be redone again. Even Shaun finds himself adding to his trail runner. I'd rather have the power and not need it than need the power and wish I had it.

[Colorado700R]

Gunny, I do need better suspension...no doubt. But I think the reason you don't have the same experience as I do has to do more with the length of your quad versus the stock length. I don't have near the corner over steer on my extended swing arm as I did at stock length. But, with that extra length, we also loose a touch of cornering speed and overall nimbleness required to run GNCC.

[Krandall]

Krandall - Is the X2 installed on the atv I timed at St. Anthony's? I felt that low end, is was nice but I didn't get a feel for it because I had to return to the trailer. It did feel really good.

Yep, that's what was in there.

[funyun]

What about the turbo?

[Alkire193]

What about the turbo?

That one im happy to share about. Glad you asked. Racer Productions (owns and operates the GNCC) said they wouldn't allow it to run. I had them on the edge of allowing it for one season because the GNCC rules are vague, and the AMA rulings say no superchargers and nitrous, then in another section they say no turbochargers (conflicting rules). Also, AMA states things like, no hi comp pistons, CC's must be stamped onto the cylinder, etc. No one follows the rules, so I asked if they would let me slip by with a turbo. They almost went for it then deemed it an unfair advantage that could cause a danger to younger riders (being run down by awesomeness). The turbo will still be built, im still very interested in completing it, however a second build was started for the actual racing. That is what this thread is about.

Also, the first build contains whatever this build doesnt so I can mix and match. Fox floats on one, EXITs on the other, OMF/ Douglas wheels on one, HiPer on the other, Maxxis Razr 2's on one, GNCC's and GBC afterburns for the other (afterburns for muddy races), etc. So if I decide I want to exchange a part its right there on the other quad.

Colorado- I agree, I wouldnt go beyond +2 for GNCC. I had my +4 in the woods and it was fun but +2 would be ok I think with the right gearing and mods. Definetly cant be too wide or long for XC races. .5" wider each side and +2 long is enough IMO

[preddy08]

If you serious about racing GNCC a 727 105 motor with a venom 14.1 piston, that would be plenty! Do a +1 port, hi compression, with a X-2 and a +3 TB. There is no way in HELL a 54mm TB would stay on in a full blown GNCC race. So far I havent had a issue with mine, but its in the back of my mind at ALL TIMES! Duals are out of the question too. A proven Sparks exhaust is simple, light and makes good HP. You will tear up a set of duals in no time with long travel shocks and all the harsh terrain. I would rather give up a couple of HP in the 6000+ RPM range for the insurence of not having exhaust issues. If your building a GNCC bike you HAVE to build it 100% that its not going to break down. Studs, Orings are all parts I would use if going high compression. I would leave the SCE gasket alone. The MLG's are just fine. I've been running it for 4 years with no issues.



FYI its Shawn, not Shaun

[Alkire193]

Thanks Shaun    My mistake, I knew it was a 50/50 chance to get the spelling right when I was typing it.

That's the first time I heard that before. 54mm fall off? Why can't they stay put?

I've got the Sparks Exhaust on the list already. I have seen a duals Raptor at GNCC and they didnt finish pretty. The whole sheet is built to be reliable, thats why I want to back off the bore and keep with the stroke. Definitely Hi-comp with belly skids and then a rotor/ sprocket guard from HSDRacing.com . Fuel tank is going to be made to have a 4 gal capacity. The list is huge to have this thing done right. But the motor is something id like more input on. Keep talking, I was hoping you would reply on here eventually.

I thought about skipping the FCI intake and going with a more OEM set up, larger intake hose, larger filter but keep the airbox with an Outerwear's filter on the top and possibly and Outerwear's on the filter itself for the really muddy races. Or races where I ford a river. Otherwise I need to find a way to protect the filter in the FCI w/box set up and im stumped on that.

I was also thinking of stripping the wires and cables for the lights and trying to do a one off airflow kit like the 450's have. Seal off the Raptors hood and flow the air through the ducting where the headlights should be. Its been effective for the 450 riders I see with it and the Raptors radiator gets blocked almost every race. Its a better use than having lights ill never turn on. Any thoughts?

[preddy08]

I've been meaning to replay, just havent found the time.


I dont know if I'd worry too much about the grill and mud. The race I did was a nasty sloppy mess. Ranined/snowed most of the race and this is how my bike looked half way into the race.

[Alkire193]

This is my build thread, not "Preddy shows off his awesome racing photos" thread   Look at the determination in his eyes  
What race was that where they had you riding at night?

This is mine after I got her home. Halfway in it looked about the same (we raced after it rained all week). One female rider I passed was sitting on a hill, her quad sunk to the handlebars in the river I had to ford. Gotta love it



I learned a lot from this race. Handlebars were too low, suspension was worse than stock, atv was too low, HC2/Ebay Filter/TBR exhaust = FAIL against built 450's, front tires were stock AND bald, goggles were useless after 10 minutes, radiator was left exposed, no airbox around the filter, bad nikasil coating caused smoking and power loss. 36/15 gearing is stupid on a 686 with 40hp , no belly skid installed, installing your bumper with bolts instead of zip ties makes it stay installed longer.....*sigh* glad I wont be that unprepared again 

[Spartan]

Nice Colorado, I used to have one of those trucks

How have those C-series rears held up? I have those on both my raptor and yfz, and was wondering if they ever had problems in extreme use conditions...

[Alkire193]

The studs wore out the holes very easily on the 2 sets I have owned. Honestly, ive never had any issue with the wheels when I race. But you can bend them or slip a bead easily. As for a basic weekend warrior wheel, they do ok. 3 out of 5 if I had to rate them for average weekend trail use.

[Spartan]

I never really noticed that with my lugs but I'll keep an eye on that. And I think I have ripped a bead already, I had a problem with one of my rear tires staying up, even took it to a tire store. ended up filling it with slime which throws off the balance.

What intake system were you looking at again?