yeah that’s what im thinking. it ran awesome the first two days. It seems to get real bad when i go up hills.
Opti-sparks hate life in general. There are kits you can buy to eliminate it which would be your best bet
yeah its going in to the shop tuesday
switch it to the LS1 individual coil pack setup.
Told ya to buy my wagon man! I’ll race you to prove it, once that opti-spark junk is taken care of. :tongue
Fastest quad i have ever riden
Ride it with this build sitting under your ass and you’ll be more amazed. :ohnoes
Thanks for the praise dude!
then you need to ride more quads!
bored out 450’s are no joke!
You should really take this for a rip dude… definitely won’t take corners like yours but it’ll probably pull you on straights pretty well.
no doubt im sure its fast…but I have done my fair share of MX races in the AM class and have raced everything from ESR lonestar 350r’s to my current 450 Hybrid…
BTW, my quad weighs under 300lbs… yz426 motor with a Athena 445 big bore, cammed, ported head, high compression piston…runs strictly on VP racing fuel
my cousin ricky can attest 
He has that 520cc Quadzilla in a lt250r frame…
BTW, I own a 100 acre MX track…If your looking for a place to ride, shoot me a PM. I only let a select few ride there so I gotta like ya
Sounds like we need to line em up
Lets do eeet!
Mine is probably 340lbs as it sits now, but it could be a little less. I Took for a lot of stuff to help with what I could for weight. Unfortunately I can’t afford VP every time I ride so I went with 12.5:1…
It’s be a good race. I know it wouldn’t keep up around a track, but I never go to tracks. Two completely different machines when it comes down to it.
My brother had a lightly modded Quadzilla for a short time, bored .080 over. That thing was fun!
As for the track invite, if I keep this thing and get a trailer, I’ll let you know.
lolllL
I only use gears 1-4. I stripped out my 5th gear shift fork right after I bought my quad and havent split the cases yet to replace it. I never hit 5th gear anyways which is why I haven’t got to it
yah, my quad is a 100% MX machine…I do ride it on the ice in the winters tho.
Ah that sucks. If I had my parts bottom end still I would have taken out that fork for you to try. 
Yeah, I can tell just by the sounds of it. My quad has never seen a track, unfortunately. Hella fun through the trails and fields, when they were open.
Depending on how well the sale goes, I may have some valve shim kits I could let you use when it comes time to shim your valves if you need some. I’m sure you have the same size shims as my head.
my quad is 50" wide, so trails are nearly impossible for me along with a 4" ground clearance lol
are you familiar with transmission work on the 4 strokes? I can take a 2 stroke apart with my eyes closed, but havent done a 4 stroke yet, which is why I have been putting off fixing 5th.
as far as shims, I have titanium valves. I have rode my quad for the last 3 years and it still starts/ has the power like the day I brought it home…
My sister just had to shim her 250f…she only had a season of racing on it.
I’ve split cases to do cranks and put them back together and have pulled transmissions apart but never with intentions of re-assembly. With a fsm I could do it without issue though.
All 5-valve Yamaha’s have ti valves IIRC. The seat is the wear item (valve wears some too obviously). I check mine at the beginning of every season. In the case of this engine, I checked them after my first oil change at one hour and after my third hour since everything was fresh.
Doesn’t hurt to check. Normal wear makes them tighter, so quieter. Most people don’t think that way… sometimes buckets and/or lobes wear and make them louder but thats not very common after initial run-in!
ahhh see back in 04’ I bought a brand new Honda 450R…That didnt come with titanium valves but I pretty much turned that thing into a tuna can within the first 3 motorcross races with it, so it didnt stay around long. Biggest waste of money I have ever spent
On a side note, like I said, I am somewhat new to the 4 strokes…nice for you to correct me!
haha, id rather not race you George, ill save my self the disappointment.