YFZ 508 Start!

[cumminsforya001]

...run low compression piston? whats the point of spending the money on a big bore if your going to have no compression- big bore it- 15:1 comp. that thing add some alky and some nitro and watch ur dollars go to work. add a big bore kit and keep the 11:1 compression and just give me your money because you might have picked up 2 hp. and i recommend a stroker kit before a big bore...bottom work on up. not up on down. why tear it down 2 times more...

[SGTHECoDGAMER]

@yamaha1owner I got the YFZ 450R SE 2011, and you gotta run it at a min. of 91 octane. I just use Super and it runs fine. I pay about $5 for a full tank which is 2.6 gallons on the R but idk about the normal 450.

[talon250r]

Dude...goo idea not listening to your buddy...Over reving when there cold let alone fresh is what kills those motors...Always let mine warm up for atleast 3-5 minutes...any vids of it in acton?

[300exrider420]

what causes the whistleing noise when you rev it i dont know if its the exhaust or what my trx450r doesnt do it and its a big bore with a full sparks racing exhaust and alota other mods all my buddies 450s whistle and mine dont but it sounds so sexy

[greenblazemike426]

@300exrider420 most times, the whistle you hear is the intake sucking in air. thats why you hear it more from built motors, because they draw more air

[TastyTortilla]

the seat magicly appeard lol

[lelxh03]

what size are your back tires?

[Muddrman300]

how many camshafts does a yfz 450 have

[Muddrman300]

how many valves does a yfz 450 have 

[redneckchannel1]

@Muddrman300 5 valves

[yamaha1owner]

hey is it true that when u get the big bore kit like this that u absolutly have to run 111 octain in it?? i herd if u dont run 111 in em after big bore kit they will gernade or blow up? is that true cause i damn sure aint getting a big bore kit and having to pay $10 a galon for gas,,, and is it true u have to run 91 or higher when yfz is stock? iv aways ran 91 or 104 octain just incase it was true..

[yamahagytrracing21]

@yamaha1owner nope i ran 93 in mine and it ran fine

[MrRexable]

@yamahagytrracing21 how much money would it take to build a 450 into a 508

[trd1717]

@yamaha1owner.. most manufacturers recommend if you run over a 12:1 compression piston use race fuel but 12:1 and lower 93 octane is safe... thats just recommendations though my opinion is see how it runs on 93 before spendin the big bucks

[1nbansheeclimber]

@yamaha1owner its all in the compressioin ratio, when ordering the kit dont run the high compressioin piston.

[yamaha1owner]

hey is it true that when u get the big bore kit like this that u absolutly have to run 111 octain in it?? i herd if u dont run 111 in em after big bore kit they will gernade or blow up? is that true cause i damn sure aint getting a big bore kit and having to pay $10 a galon for gas,,,

[godd1964]

BRAP BRAP !! the sound is so good :O

[Fordoyfz06]

Hey buddy you can buy a 501 bore kit hot rod crank with all the gaskets on eBay you only need

To buy your own cams should take to at least 60 hp I was gonna do mine until I found out my crank blew my case up as well

[theblackswordsman69]

hey wut parts do you have on that i wanna big bore mine i have an fmf powercore 4 exhaust. I want to double or triple the power,horsepower,and top speed on my yfz 450 how would i do that exactly.

[Matt06yfz]

@TheCrRider125 thats not true, only the 04-05's have that problem, i have an 06 and it runs fine without the lights on the machine.

[uae3276]

hi, i have just upgraded my yfz to a big bore, i am at see level and have an after market exhaust, i put a 45 main jet and a 170 pilot jet, the problem im having is that it is hard to start and doesnt stay running, it backfires somtimes and revs high sometimes aswell, do you have any idea what i should do?? bigger jets??

[yamahagytrracing21]

@uae3276 yes bigger mine had a 50 and a 190. but you need to go by your elavation

[twanweazy]

@uae3276 Your bike might be running lean.. Try smaller jets.

[uae3276]

@twanweazy hi, got it working, was the spark plug. problem no is i feel it has enough pull, since i can hardly pull power wheelies, would this mean my main or pilot jet is to big or small, btw i tried a smaller pilot jet and it made the bike start harder so should i move it back up? thanks

[nickernosher]

@twanweazy hmmmmmmmmmmmmm, think about what you said again lol

[TheCrRider125]

@Sandeep9201 if it is a 2004 to 06 your have to run the quad with your lights on. it came from factory without the capacitor they put on th 07 and newer quads

[mossow71]

nice yfz man.does that 508 increase the top speed by much.i would put in it now a dynatek programmable cdi then put a 15 tooth sprocket on front and 37 on the rear get more top end out of her.

[hondaryder042]

I hateeee puting on carbs.... Putting the boot that hold the crab onto the motor is a bitch to put on.

[MrYfz480]

please answear

[MrYfz480]

Hello, I have trimmed my atv with cylinder works - big drilling 478 But the starter can not start it, what should I do?

[yamahagytrracing21]

@MrYfz480 does it try to turn over? or does it turn over and not start?

[MrYfz480]

@yamahagytrracing21 It's going to push it, to when it goes very nice. but the electric starter does not work, it may be that the starters are ødlagt? For when I turn off the starter so RUNNING it, but whispers that the starters can not go 478 cylinder. Thanks

[Sandeep9201]

one question to all the yfz riders........ i owned one before and it seemed like the battery never got charged. i had to charge it with a charger and after about 5 hours of riding the battery dies and i have to push start it. is this on every yfz or was my stator or something fuked up? does this happen to everyone? i thinkin about buying one again i ride a 700 right now.

[yamahagytrracing21]

@Sandeep9201 your stator or regulator might be bad.

[yfz450n300exrider]

did you have to get aftermarket cams since you put that Big Bore kit in it

[yamahagytrracing21]

@yfz450n300exrider yep stage 3 hot cams

[TheNuggetface]

lol your right i think i wouldnt rev it that fresh, ive blown a brand new engine revving it too soon ><

[skaterBmxerNiocK]

the gas has to flo threw

[boochiefs5]

why are you not supposed to rev it?

[grizzly5501]

is it just me or does it sound sweet

[gusocorredor]

it backfires non stop when decelerating, im going out to the trails on saturday and im worried it can harm the engine, will it???????

[yamahagytrracing21]

@gusocorredor its possible b.c its running to lean when it does that

[gusocorredor]

@yamahagytrracing21 hey, i fixed the backfire, the exhaust was lose, i noticed i use up lots of coolant, from full to empty in 3 or 4h, under the coolant pump on the right hand side theres a little hole (i believe its a breather) and its drips coolant when i use the yfz without long breaks, it only drips when i use it but i dont see it drip cus when i stop nothing comes out. could it be tht the steam comes out through there in order to keep the pressure down??

[yamahagytrracing21]

@gusocorredor one of ur waterpump seals are bad, best bet is to replace both to prevent coolant in ur oil

[bradlee101]

@yamahagytrracing21 yeah thats the weeping hole , car/truck engines have them too .. and you are right the seal would be bad if it drips from thier!

[skaterBmxerNiocK]

@gusocorredor you just tought me sumthing thnxXD mine was doin tht even tho i have a small kawasaki

[scrimmy6969]

@gusocorredor turn your air/fuel screw out. if you go out 3 turns out and it still pops you need a bigger pilot jet

[gusocorredor]

@scrimmy6969 I think theres something wrong with my yfz, the timing chain was terrible, hard and long, so i changed it cus it skipped a tooth, and my yfx smokes white and like it doesnt idle even if i tighten the cable but as soon as i give it gas it runs normal but shuts down as soon as the switch on the acc lever closes :S could it be the throttle position sensor?

[gusocorredor]

@gusocorredor *YFZ

[scrimmy6969]

@gusocorredor if your bike is smoking white then i would assume you need a top end rebuild. white smoke means coolant or water is entering the cylinder. i have an account at Yamaha and can save you alot of money on new parts. i can list on ebay if interested so we are both protected. what jets are you currently running? what mods?

[gusocorredor]

@scrimmy6969 well i live in europe but i have Yoshimura exhaust, k&n filter and jets, high comp piston, new camshaft chain. are there any possibilities it could be from the oil in my air filter cus it was dry and i put a little bit of oil. how much do you think a top end will cost me, the valves are new and the water pump seals.

[scrimmy6969]

@gusocorredor what jets are you running? you at sea level?you living in Europe is no problem i ship parts there all the time. do you want a complete top end rebuild, cylinder, piston with rings, gaskets? i can also save you alot of moey on high compression pistons as well. let me know. thanks

[boochiefs5]

soungd great dude how many 4 weelers do you have

[yamahagytrracing21]

@boochiefs5 just that one

[boochiefs5]

@yamahagytrracing21 oh just askin cause i saw more

[gusocorredor]

Nice job, watched every vid for the 508 assembly, is it safe to buy an atv like the yfz with a new cylinder head? i saw a 2005 yfz with a 2006 engine and it had new titanium valves and a new cylinder head, does this mean something bad happened to it and they had to change it. the guy said it was cus his cousin had a 2006 yfz but he crashed ( only A-arms damaged) so he got the engine since it was a year newer and his cousin bought a new engine. why would someone change the cylinder head???

[yamahagytrracing21]

@gusocorredor its possible that it did blow up and crush the valves. but if u buy it make sure your upgrade to the 07 oiling system b.c if its a 04, 05, or 06 it will likely blow up again at somepoint because those years had oiling troubles. but if u buy that mod u should be safe. and dont let them make u pay to much for if b.c u can buy a new yfz 450 for 4500.

[gusocorredor]

@yamahagytrracing21 i finally got the yfz, i ran it today and it backfired non stop when deccelerating, i didnt even got half throttle and it did it, what do i do, can you post a vid??plz

[yamahagytrracing21]

@gusocorredor ok what octane feul do u run and has it been jetted? new pipe or anything?

[gusocorredor]

@gusocorredor it has yoshimura full exhaust, k&N air filter witthout lid(i will put it on), has high compression piston but i dont know jet number, but it has been jetted, gas here is bad i think premium fuel here is 91 and regular which i think contains lead is 89

[dirt23bike]

Sounds pretty good man! Can't wait to see it in action!! Check out my new video!!

[elcubeo]

Good Job man! I agree w' the camera man. "break 'em in how you'll ride 'em". The best thing you can do on a new break-in is to ride the living snot out of it under load. Free-rev is bad, but you want to load those piston rings so that they seat properly against the bore. You also want to unload the rings and put them under suction on hard decel. So for the first hour take it out in like 2nd gear and bash it a little, and chop the throttle completely. Try not to keep the rpm constant.

[SOHCGT]

Sounds like the pilot jet is to small. Did you ever get the wheeler to rev up without dying?

[yamahagytrracing21]

yea i need like a 52 i have a 50 now

[origionaldz]

Sounds pretty good. I'd say take it easy for the first few tanks just to seat the parts.

[BIGSEXYNANDO]

nice job!

[yamahagytrracing21]

thanks man

[sh0rtsleeve]

awesome! i bet u cant wait for summer LOL

[yamahagytrracing21]

no i cant

[GhondaW]

see man ill told u it would run-my dide that right after rebuild also-my was backfireing like crazy-till i fixed the plud-it was loose-great vid n i have a trx 250x

[yamahagytrracing21]

hows that run?

[GhondaW]

pretty good i am currently puting new guides-cam chain/cam n rockers ill have a vid up when its done

[4wheelmadness1]

Ohh hell yeah man you going to let me ride it sometime

[yamahagytrracing21]

yea come up

[4wheelmadness1]

yeah man when i get some free time i will

[ltz250boy93]

badass

[yamahagytrracing21]

hell yea man

[grusznikk]

grate im from poland in europe chceck my new video of my yfz 450 wich i paint and make upgrades(sory for my anglish)

[4wheelmadness1]

Old buddy its english, just saying :)

[TheHondaAbuser]

I JUST SHIT MY PANTS! lmao sounds exactly like my ttr start it... it dies my choke doesent even work lol cool vid make a ridin vid or a engine blow...

[yamahagytrracing21]

enigne blow fuck no lol

[gtyamaha]

LOL ahahaha. what a retard. "YA LETS GO BLOW MY BRAND NEW REBUILT ENEGINE AND SEE HOW LONG IT LAST SO I KNOW FOR THE LONG RUN!"

[kryptonicloser]

thats sweet shit man glad to see ya got er all done now bet ur pretty happy now

[yamahagytrracing21]

haha yes i am

[dmaheryfz450]

the beast is alive dont rev it to hard yet till the rings are wore in by the way it sound sick

[yamahagytrracing21]

yea i know, and thanks

[vmxrm85]

man i bet it'll be fun as hell

[yamahagytrracing21]

yes it will :-)