Tuning The Yamaha Yz 490!!! BIG IMPROVEMENTS

I decide to dig into the carburetor on my 1987 Yamaha yz 490 to see if I could fix the bogging issue it was having.
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[@duramaxdave4602]

That expansion chamber is all dented up believe it or not that really makes a difference on a 2 strokes performance.

[@foreverhungry84]

i imagine it would affect the pressure wave

[@RcBasher5000]

It’s also cracked watch closely when he starts Reving it

[@steelyc3506]

@@RcBasher5000 Or the O rings could be gone

[@damonkoebel8141]

The O ring is probably gone.

[@James79561]

All his crap is fuckd

[@miggs2964]

Yes at least we are making some progess 👏👏 you will get there in the end. keep at it i wanna see this 490 run as it should

[@ChrisBrown-yk3hw]

He sold it .lost money as well

[@Hanky_Bannist8r]

Going back to factory settings and jets would be ideal. Re-jetting should only need to happen if you add an aftermarket pipe, have head work done or are high up in elevation. You're doing a fantastic job at troubleshooting this old dinosaur, it's definitely not easy and very frustrating.

[@stevec5742]

This guy starts troubleshooting his bikes by spraying WD-40 on the rotors

[@dudegalen]

@@stevec5742 and all you do is hate on other people to make youself feel better, im glad @hanky is posting constructive comments that will help other people with these bikes like me

[@stevec5742]

@@dudegalen I'm not hating on anyone. Here's a constructive comment that will help you. Don't spray lubricant on brake surfaces

[@dudegalen]

@@stevec5742 when did he do that lmaoo

[@lewishowe2285]

Steve c first video you are referring to yeah? I thought the exact same we're going to have some fun here boys 490 2 stroke and fresh wd 40 on the only disc brake 🤯

[@reubenswinkels9742]

There is such a thing as a lean bog. I typically would say a bog is lean, choking up/stuttering is rich. Also the best way to check the main jet is to do a plug chop. You put a fresh plug in, run it full throttle through all the gears, then cut the engine. You can look up videos on how to read the plug.

[@johnbleeck3608]

yes Reuben, that is the right and only way too see how the settings are !!!

[@listenupfools731]

You accomplish the same thing by cranking the motor,let it watm up,then just peg the throttle,and hit the kill switch.perfect plug check technique

[@brendanyendall4085]

Love this bike. I'd burn out all the carbon build up on the exhaust and replace the header gasket-it looked like it was leaking when you blipped the throttle. In my experience 2 stroke exhausts are vital to running well, along with the carburettor. Once that and the air filter are golden the carb will reveal if any issues are present. Cameron Niemela has great videos on carb adjustment if you haven't already checked him out. Keep up the good work bro!

[@rigguyjt]

When you're laying on the pavement in the street, it's running right. Hopefully you don't end up on the pavement.

[@OldestYoungenInGuidePost]

Rigguy I I want to see it running right 😏😋😋😋😋😋

[@rigguyjt]

That's messed up

[@OldestYoungenInGuidePost]

Rigguy ( in a whispered voice) He'll never get it running right 😘😳😋😋😋🤷🏼‍♂️

[@rigguyjt]

If he follows the correct steps he could.

[@Garmoo5600]

My Dad's mate got on his mate 490 thinking he could ride any bike, one blip of the throttle and he was being dragged down the road by the bike Lmao!

[@sarcastropheoffroad9761]

All factory jetting is assumed at sea level, your altitude, if significantly more than sea level requires leaner jetting from the get go. You’re on the right track, seal the pipe at the head and check silencer packing as well. All air leaks on a 2 stroke WILL effect efficiency.

[@aidanley3410]

No he lives in Wisconsin so I don't think that we are to far from sea level

[@BaltaM4ster]

you should have started with air filter and pipe since is the easy stuff and might mess the carb

[@waylonlegend4603]

Air filter and pipe cost money kiddo

[@Ghettochappy]

I give you credit for trying to fix it the right way! Thats the way to go forward

[@lex1945]

You should start watching some Cameron Niemela vids (and get Lectron to sponsor your carbs for all of your dirtbikes, LOL!)

[@n2vxc]

I highly doubt lectron would put there product name anywhere near his projects considering most of what he buys is junk. Good thought but lectron is in business to make money. No matter what carburetor you out on a work out engine, it's still junk

[@mattryan6832]

n2vxc he makes money off the bikes, it’s not like he’s racing them. Lets see your bikes

[@FordRanger-ih9wq]

@@n2vxc FUCK U IDIOT

[@judeboyer4996]

N2vxc init whers ur bikes

[@matthews852]

n2vxc *their*. This is basic shit man.

[@thomasmcdougall8059]

Lay off the oxys man your voice is starting to sound like a FMF pipe

[@2vintage]

Lol I was really sick when I was taking this video.

[@henrik7966]

@@2vintage u mean really high?

[@outdatedfarmequipment2702]

@@2vintage You sound sick as a fucken dog mate hahaaaa.

[@trooperj9220]

🤣🤣

[@rickwaldren3633]

Sorry bro I'm ot a oxy man I live in the real world

[@wilz6435]

Love your videos bud. Make sure you check exhaust pipe and baffles.

[@theirishaxe9405]

If you didn't notice you have a bad exhaust leak before the can so that's part of it

[@2vintage]

Yeah might need to order a new pipe

[@ste7590]

I saw that and thought the same rhing

[@lengaming1651]

@@2vintage Order a new one or fix the old one in some way, it looked like it had 2 leaks and huge dents in the expansion chamber so i think it would make a difference to get it fixed...

[@codykuiper9613]

My exhaust was leaking from the cylinder because my pipe was clogged

[@mikewiley1007]

Your air filter boot isn’t on all the way.

[@ruanjvrensburg3785]

Great video the bike is getting there can't wait for the bike to run perfect and see the top speed!!!

[@mikemiles3068]

Sounding much better, tuning is a fine art that takes time to acquire the skills, you are headed in the right direction so just keep going! 👍🙃

[@Neptonic101]

mike miles exactly just like anything else in life. Practice makes perfect

[@rigguyjt]

That's what I keep saying. What I offer is not criticism but more like advise. I've been working on these bikes for a long time and even I get stuck sometimes. I learn something new every day. You have to get used to sight, smell and sound.

[@scottwalters8090]

Enjoying your vids....especially appreciate that you're not a foul mouth like a lot of the MX losers on YT.....keep doing your thing and ignore the haters! That's an awesome old school bike!

[@Ziurkyss]

You should check ignition timing. If it is too late, it will look like engine is running very rich and if you jet it leaner it will run good but with less power and less lubrication.

[@rach84able]

Crank shaft oil seal has gone 100%

[@Midge60731]

I thought you said float height had to be set with carb leaning at 60 to 70 degrees? You set float height with carb flat i.e. zero degrees? Correct me if i'm wrong.

[@Midge60731]

@Ryan Carlen Yes, and the service manual states that the float height should be set with the carb leaning between 60 and 70 degrees. He stated this in the video. But he didn't bother to tilt the carb when he set float height. Re watch the video and you will see.

[@jaredk777]

Smoke can also help when tuning. If it is smoking a lot it’s too rich and if it’s not smoking at all it’s too lean.

[@BobDingleful]

It sounds a lot better than the first two videos. I am interested in what it would run like without the exhaust leak and see what the plug looks like.

[@dansmolen1618]

You need a trail 70, and work your way up from there! That 490 will forever be too much bike for YOU!

[@stevestewart6287]

It finally started running good, it should pull the front wheel off the ground in every gear but 5th, with a little half turn of the throttle, if it dont it is not cleaned out or just not running right. Make sure the air cleaner is clean, the plug is good, and the fuel mixture is right, and do not let it idle after start up, ride it hard right away and all the time and it should run like a beast and give you arm pump after 10 minutes, lol.

[@1176hambone]

Hahahaha! Yeah!!!

[@Rebthewizard]

Been here before I got my first bike. Been riding for 2 years now

[@ChrisBrown-yk3hw]

Some words of advice.if your pulling the carb.get a rebuild kit.your not in spec your jets a off you said it.so specs are not going to on air and fuel screws .

[@leewaken5059]

If you are following Cameron Niemela's KZbin Channel, your mechanical skills can only improve. Good for you bro.

[@jimmadonna1436]

Lee, your right. Cameron is a excellent machanic and an even better person.

[@easydoz1]

My bass boat 150 outboard had Mid Jets that someone drilled out to a larger size. So don't believe what you see on those jets. I also swapped carbs on two identical chainsaws One Old and One New. The old one for some reason ran Rich with the Newer ones carburetor. If that helps👌🏼

[@voodooinc7935]

Chrits lad... It finally starts sounding like its got the beans but you didn't give it the beans? First gears blips aint gonna cut it. We want that front wheel kicking up through 1st 2nd n 3rd!

[@matthews852]

AcousticNRG you really need to take some sort of basic writing course if you’re gonna try to comment on here.

[@chestertownelectric6290]

490’s love a more open air box. I drilled 9 one inch holes in the left side of the airbox and pushed in some plastic soffit vents. It ran super great after that.

[@Del1650]

I would buy a few different sizes for the main jet. I’ve never had any luck with factory jetting specs. I have always had to jet by sound and feel and it’s trial and error. Another good way is to go full throttle in a higher gear. That way you have more time to listen and feel how the engine performs without worrying about being thrown on your back. Sounds like your making good progress.

[@mikelwmc]

Leaking from header at cylinder. Air leak. Good video man!

[@mikelwmc]

Did you put in a new plug? Sorry if you did I didn't notice.

[@mikelwmc]

Also ohm out the stator it should be in service manual

[@frankieray2999]

I've owned hundreds of 2 strokes I've never messed with jet settings and nothing more than cleaning carb and they all have run perfect

[@martinrobb9115]

That was so relaxing Joe you nearly put me to sleep with that so soft voice of yours.😎😎😎

[@chefboiard5468]

Martin Robb I’m deaddddd

[@wisecampmotorcycles8258]

Float height should never change, unless someone has messed with it before.

[@HUSKY7-1]

No ambulance so still not running right

[@dudegalen]

very helpful video,imma enjoy learning more about bikes as i go, dont let tha haters get ya down nobody knows everything from the stary

[@CMX96]

I think you should incorporate more Go-Pro clips with the audio of you talking dubbed over the clip like you done at the end of this video, don’t mean to offend at all but I think it was good compared to the usual way as you are always very excited when you drive your bikes (as is everyone lol) and sometimes say things you don’t even really mean just in the heat of the moment and then think why did I even say that when watching it back haha... Anyway, I think you were a lot better at putting your points across this way and also it’s way easier to follow a calm voice than an excited one haha! Just a thought bro, really enjoy your videos by the way keep doing what you do🔥👍

[@hardtorn]

I’m shocked you didn’t just peg it out and blow it up. Stopped watching your channel some time ago because I couldn’t stand watching old bikes being run hard until they blow up. Glad to see this old legend on the channel.

[@derrick6483]

Good job going step by step the way you did. On the last video I thought for sure it was lean but seems like I was incorrect. Good stuff man. Cameron N. Is an excellent resource for anything Moto. Glad you ran across his videos.

[@rigguyjt]

That carb slide could be your issue. It looks really worn.

[@buttery2014]

Was kinda crusty lookin huh

[@rigguyjt]

Yup, worn on that one side.

[@jayz1719]

You have a big following on this project. Please keep us all posted and buy your jets. Buy big and small jets. There cheap. You'll get it. It does sound rich. But is it smoking alot? Try pulling your choke up and see what it does when you try revving it out. Then tell me what happens.

[@calebmartin2457]

“Were going to higher it into a different position” you mean raise it lmao

[@ianmangham4570]

He's hilarious

[@Steve8624]

are you talking about cameron niemela?

[@jhmonthetube6339]

Did you do the squish band ? This is the first step in getting it to run clean on the bottom. Take the head to a competent shop that knows how much to mill. Then rejet and it will run like a bat outta h-ll without doing anything further. No charge.

[@rigguyjt]

Be careful with that lean situation. It's always better to keep the main jet as close as possible to stock. Pull that air screw out and check for wear. Also take needle out and drop it into needle jet and make sure needle is not worn. If that carburetor is worn out you could ruin the piston. A worn out carb could trick you into false settings. I wouldn't say it unless I had not had that problem before.

[@gtisid]

did you check if your ruler starts measuring from the end of the ruler? most kids rulers don’t , engineers rulers do.

[@gtisid]

i would order a jet either side of standard on main and pilot

[@claywatkins2003]

Great vid but why is it always a carb issue with these bikes

[@jamessharp9790]

Clay Watkins ? Old gas sits in carb . Plus most owners never properly jetted bike and stock settings usually rich in order to try to prevent seizing

[@bikelifereek]

Its a old bike

[@rigguyjt]

Because a lot of people don't know what they are doing with carburetors.

[@jimmadonna1436]

The BING 55 was the answer to it not making detonation noises.

[@stevec5742]

At the end of the video the clutch is the problem lol that's why the bike doesnt have powerband

[@johnbleeck3608]

Always start at the basic : with a clean air filter, standard jets, air 1.3/4 open ,needle in the middle ,if its running still bad ,look fore leaks and if that is not the problem check youre piston!! Good luck !!

[@rigguyjt]

Float should not be depressing the button on the needle valve while measuring if done properly.

[@89HondaCR500R]

i would have suggested the crank case seal may be leaning out the mixture

[@stevec5742]

Now it's the clutch...this guy is petrified of powerband. Shine that baby up, spray some WD on the brakes and lemme buy that off you

[@dr00andrew]

another thing that gets overlooked when it comes to tuning is the mechanical shape of an engine. if you have a worn out top end, dirty air filter, broken or chipped reeds, a silencer that needs re-packing, air leaks coming from the airbox, reedcage, or even a bad spark plug, you will never get it right. it seems to run better but those factors will affect the jetting and overall performance of the machine

[@jaredk777]

Has the bike been honed/bored? That might be why it doesn’t have stock jets

[@paulhagerty2773]

Pay attention, The stock jetting components are all close, except the needle jet. Stock in my bike was a Q8 with a single taper needle 6F6. Fouled plugs and ran poorly. Went to a Q0 needle jet with a two taper needle that followed the initial taper on the 6F6 needle but had a different end taper. After the jetting change, I never fouled another plug and the motor was quite powerful indeed, also followed a Yamaha bulletin to take a 14mm slice from the divergent cone inlet. And get the dents out of the expansion pipe

[@Foryourinfo369]

Watch the video where Finnegan explains how to read a plug. Helped me tremendously. Also don't forget you can mess with timing as well.

[@danielprc1]

Look at your spark plug also, it will tell you if its running lean or rich. Plus check the gap. And definitely check the air filter

[@fishstickkitty8068]

Bravo for doing your homework and being willing to learn 👍 ...that Cameron dude is good too 😀

[@GamersUnion101]

Back sprocket is pretty worn also

[@megamindtvsydney3967]

Oh no you sold it bro? I guess that’s what you do! Good on you ! Keen to see what’s next regards Al from Sydney

[@James79561]

Just gave this guy the benefit of dought ! Watched 2 videos and realized he knows nothing . His videos are more what not to do . A real bike shop would fire him right quick .

[@glenncrockett4451]

Lol I agree, some of the shit he does makes me yell at my screen lol. One thing he needs to do is chuck all the WD40 shit is only good for spraying water out of electrical stuff, IT IS NOT A LUBE!

[@megamindtvsydney3967]

Awesome!! Very good video ! Hello from Sydney Australia!

[@foreverhungry84]

put everything back to stock settings and work from there. don,t forget to check the air filter.

[@yeti8it396]

THIS bike with a really good tune and the correct rider will raise the front end up in every gear .

[@dallasfingrocks]

I didn't see but did you check the needle size and make sure the reeds hold water?

[@mikeenos4040]

Had one of them ,they are a monster. It will get away from you quickly , not for the beginner that's for sure...

[@ChrisBrown-yk3hw]

Evey bike you own has carb issues.that tells u something

[@FordRanger-ih9wq]

U DON'T EVEN HAVE ONE AND IF U DO IT HAS A FUCKING BIRD IN THE CARB

[@lengaming1651]

@@FordRanger-ih9wq how do u know lmao

[@FordRanger-ih9wq]

@@lengaming1651 I JUST KNOW

[@spreaddeezhazelnutz7511]

JakeRyall500 WHAT’S WITH THE ALL CAPS?

[@paulpz04]

Dude said on his cr500 vid that it wasnt getting into the powerband and i think he even said he thinks the powerbelt might be stuck🙈..best case scenario he mightve said powervalve and no CR ever had a powervalve..being that im a huge vintage enthuisiast ive always liked what this channel was doing but seeing how bad he is at simply changing gears and having common bike knowledge im starting to wonder is hes just a poser that makes vids about his dads bikes that his DAD buys and sells

[@tedadams5448]

I had one of these bikes. Had to take to Yamaha mechanic for rejeting and needle adjustment. This bike will fly. I used it for cross country racing. It is still to rich. High idle due to bad combo on carb and needle. Mechanic can have it right in one day

[@rickwaldren3633]

Try adjusting the air mix screw 1 and A 8TH SND TH BAFFEL I FIT PLUGED HEAT IT WITH A TORCH TILL ITS RED HOT THE TAP ON IT TAKE IT OF FIRST RUN IT IF T POWER TRIPLES THEN ITS THE BAFFLE RIN IT WITH.NO BAFFLE FOR 4 HOURS TO CLEAN IT OUT👍

[@wisecampmotorcycles8258]

The air screw is only for idle speed.

[@robdixson196]

When it scares the shit out of you it's running like a yz490

[@Hutch_moto]

I would raise the needle one clip first and try that , and service air filter may be over saturated with oil , whats your altitude , if your close to sea level then factory size main should be very close , big bores are hard to tune , that slide has alot of wear , might consider putting a 38 mm air striker carb from JD jetting , or a lectron carb .

[@Nupealoop]

I appreciate the enthusiasm from someone so young. BUT it gets tiring with the lack of research with a new toy. I don't know everything although in first vid it was posted as a 1984. Also check the bike over first. I have owned many hacks and you never know what is rigged just to get it sold and may kill you like bare brake pads, missing axle nuts, etc... Appreciate the channel, but it is painful with the mistakes especially not winding out the 2 strokes. My rule I was taught per 2 strokes: warm up the pipe then ride the hell out of it. I'm no hero and these beasts are scary. Trying to sort my 85 490 out (stock carb was junk went Keihin).

[@MrTamiyacowboy]

remember the tuning will change due to weather , colder weather means air is more dense , hot weather air is less dense , i would personally recommend you purchase a few sizes up and a few sizes down on jets . start with the larger jet first ie a 240 , see what the top end feels like, if its sluggish and bogs , start to go down in jets by a couple of sizes , until you find the sweet spot. winter riding you may have to retune the carb when the weather shifts and the air is more dense as its gonna throw off the summer tune somewhat . you are totally correct , pilot jet and airscrew are 0 -1/4 throttle , 1/4 throttle to 3/4 throttle is usually the carb needle , 3/4 to full open throttle is the main jet

[@KentRoads]

Your needle looks slightly bent?

[@keithchilcote8088]

Great info thanks. I have a 490 I bought that runs perfect on full choke. I've cleaned the carb and set the float with no change. I'm wondering if I have a vacuum leak. Do you know what that extra intake hose to a cannister is for (some kind of vacuum accumulator?)? Maybe that is my leak source.

[@rigguyjt]

I made a depth gauge for mine with a piece of wire with one end as a handle and the other end bent at into a 90 degree angle with right angle depth cut at proper clearance length. Worked great.

[@luke9299]

Had an exhaust leak on a old big bore, it ran like shit until I fixed it

[@henrik7966]

I have a slight exhaust leak on my Suzuki ds80, I should probably fix it before I keep trying to jet it then lol

[@jorrickvanos5411]

When you first adjust the needle, than the mainjet you're waisting your time. First go high in main jet, then you can build off in jets. Then the airscrew and finally the needle. Because needle and air screw are finetuningen. I think you already knew this but why aren't you doing it?

[@tylerbell8285]

Bingo

[@Oscar-sg7bw]

give this guy some slack he will learn as time passes im 13 and i know a lot about bikes and i took me time to learn everything thks to my dad

[@twisted-xh6066]

The old bikes are always cranky. You either ride em hard or burn through plugs

[@josha5563]

I’m glad to see ur getting this bike running right I guarantee once u get it 100 percent it will scare u.. anyway I have a 96 cr80 nice bike if u wana make a deal it’s for sale let me no

[@punkin7144]

27 plus OR minus 1 millimeter!

[@boburwell9921]

Still have my manual 🥺miss that beast

[@sb-ant6457]

Why two fuel taps?

[@mikelwmc]

Those are vent lines

[@MatFlyinFoolHarris]

Yeah, gotta fix that pipe or get another one. As was stated, holes and dents will effect performance...

[@lukewalton7352]

Atleast he didn’t blow it up in this vid😂

[@lukewalton7352]

zack coeling And atleast I don’t fucking abuse my bikes by pinning them going down a road to see which one goes faster and blowing them up like a dumbass.

[@trevorcapune655]

fuck off Zach Coeling

[@hrsey71]

as a general rule, if you Are more than 2 turns out on your air\fuel screw go up on pilot one size. also, there is exhaust coming out of places it shouldn't be..

[@vaughanjones2303]

Beast of a bike ♥️💯

[@willyrida274]

Hey man good to see that your studying up and getting it running closer to how it should👍

[@nova9823]

Love the channel

[@Fatpig-fq3vb]

These were known as king of ping the 490 fits in the yz 250 frame pretty easily and then you get better handling and geometry but if your a purist that would be vandalism lol.

[@bluebeast6789]

At 13:00 you need to fix that exhaust leak

[@eddiecash9417]

2vintage Hope you get that ol'girl sorted and crispy on the throttle, But you need to get that exhaust sealed first and make sure air filter is cleaned and oiled correctly. I'd never trust what it says on the side of those main jets unless you fitted new and know they are bored as they state... People can oversize jet bores by over zealous cleaning or muppet tuning, so I'd look at buying jet's ranging from standard setting and down to 0.5 past whats in the bike now, sure its not far off, but unless you can be 100% sure those jets have not been tampered with it's best to air on the side of caution and tune down from rich or you'll have a melted piston and that will suck big time... That bike should stand up and smash your teeth out with the handlebar brace when running correctly in most gears at full throttle on pipe (if you ride it right), clutch slip is not gonna help to gauge response though, is the gear oil correct as car engine oil can cause wet clutches to slip because of additives ? (sorry if i missed oil change vid) When you do get main jet correct you will know and if the main that's in there now is right I'd come down 0.5 at a time until she pulls ya arms out of their sockets, then go back up 0.5, keep it slightly rich on the fueling. Plug chops are the only way to get to see exactly whats going on at full throttle, but your gonna have to do a little reading and swat up on how to read a plug and where to look for the ring on the insulator and where it should be, Two strokes are finicky when it comes to jetting and there are too many variables involved to give you a fix here but do some homework and buy yourself a few plugs to sacrifice..... you'll get there in the end. Good luck and hold on tight when that ol'girl starts singing.

[@keithparady2594]

Getting close to getting it figured out

[@jeffhicks1008]

Who told you to warm up an air cooled engine for 5 minutes!

[@stevec5742]

tHe iNtERnET

[@glenncrockett4451]

I think one of the very first tools I picked up for working on motorcycles was a Honda Float Height Gauge 38yrs ago lol.

[@mxbeanz1206]

do a cheap restore on the yz490 like u did the rm125

[@colinwayland7160]

Hey boys, he is listening to y’all

[@livefastdiequick]

Doubt it

[@crffilmz7300]

Love me some Cameron niemela

[@jimmadonna1436]

Me too. He is the best.

[@theonguillory8089]

I can tell it’s very hard for you to actually troubleshoot that carburetor bro you would done better by just buying new parts for it and put it back together factory it would have been way easier and faster than thinking so hard on a simple problem