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taming the yz 85 ??

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just curious I'm about to buy my son another bike his last bike was a jr80 and i was wanting to get him a yz85, yeah a huge step.

he isn't a really ballsy go nuts kid and am worried the bike will intimidate him and make him not wanna ride. i have tried to talk him outta that decision into maybe a ttr125 or crf150.

maybe even a pit bike but he is dead keen on one is there anything you can do to settle the beast down maybe a fww???

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Out of all the 85's to jump to the yz85 is probably the worst in terms of a new rider. Start him out with a used 65 and then go to the 85. My son went from a ttr90 to a kx65, to learn the clutch and feel of a real dirt bike. IF he has to go to a 85 try thr kx, I have read its the least hit 85.

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ahh oh would the 65 be tall enough ??

are they taller than the jr80??

thanks.

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the kx65 is 29.9 in for seat height, the 85's are 32-33 inches I believe.

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If you remove the cylinder and head and bring it to an engine tuner, they can pull the power back down low. Have them reshape the ports, and shave some thickness off the cyl head.

That should do it. Shouldn't be any more than $200, quite reasonable.

If you want it to tractor even more, like a CRF100/150, replace stock reeds w/ Boyensen RAD valve. Lower the pilot 3 sizes smaller, replace the stock NBKF triple taper needle w/ a straight taper needle, and lean out the main jet two sizes smaller.

With all that new found bottom end power, look at dropping your rear sprocket one or two teeth smaller. That will absolutely kill any midrange hit if present.

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My son also wanted a YZ85 but after reading up on all the 85's I decided to go with the KX. It's a great bike, reliable and you can lug it around all you want and very rarely does it stall. If you want it to go fast all you have to do is twist the throttle a little more and it takes off. However, if I was to do it again I would have probably gone with the YZ as kids learn to adapt pretty fast.

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just curious I'm about to buy my son another bike his last bike was a jr80 and i was wanting to get him a yz85, yeah a huge step.

he isn't a really ballsy go nuts kid and am worried the bike will intimidate him and make him not wanna ride. i have tried to talk him outta that decision into maybe a ttr125 or crf150.

maybe even a pit bike but he is dead keen on one is there anything you can do to settle the beast down maybe a fww???

How big is he? My son learned on a TT-R125 for a year at age 11 and I bought him the YZ when the '06 came out last November. He is about 5' tall. Took him about a week (riding every other day or so) to get used to it.

He rides on track and trail and loves it.

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Try 2 cylinder base gaskets.

I did it in my little bro's yz80, and it worked pretty well.

how much did that change it???

How big is he? My son learned on a TT-R125 for a year at age 11 and I bought him the YZ when the '06 came out last November. He is about 5' tall. Took him about a week (riding every other day or so) to get used to it.

not sure how tall, an average slim 10 yr old.

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I was basicly in the same position.. The yz85 was extremly intimidating.. First off, I would get a set of reeds.. I just got the Carbon Tech LT reeds because i'm low on cash, but Boyseen's would be a much better choice..

Second, go 2-3 teath up in the rear sprocket.. I went one, and I noticed a small diffrence. If i did it agian, I would probally go back and get 2-3 bigger in the rear sprocket..

After that, a flywheel weight would be a good idea untill he's more confident with the two-stroke power.

I actully got a FMF shorty too.. Honestly, it was a mistake.. Way too loud, and, the sprocket made a bigger diffrence, and was 70 bucks cheaper.. It didn't nessicarilly make a large diffrence eaither.

Good luck.

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i own a yz85 with engine mods (to make it go faster)

and i wouldnt reccomend it for less skilled riders.

dont get me wrong, after getting used to it, it

huals a$$ and is a blast to ride, but still, its

hard to get used to. i came off a yamaha breeze

after 6 years of riding i didnt think it would have

so much of a scary powerband. my grandpa even

said that he didnt want give it full throttle when the powerband kicked

in.i dont think u should try to make it less powerfull

because its meant for racing, not putting around.

it will foul plugs and require a more skilled rider to

handle it in stock form. If u do end up modding it,

i would just make a throttle limiter for it so

if he accidentily hit a rock or got carried away,

it would only go to half throttle(and quite frankly,

for a less skilled rider, thats ALL ur gonna need)

Best regards,

jimmy

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i own a yz85 with engine mods (to make it go faster)

and i wouldnt reccomend it for less skilled riders.

dont get me wrong, after getting used to it, it

huals a$$ and is a blast to ride, but still, its

hard to get used to. i came off a yamaha breeze

after 6 years of riding i didnt think it would have

so much of a scary powerband. my grandpa even

said that he didnt want give it full throttle when the powerband kicked

in.i dont think u should try to make it less powerfull

because its meant for racing, not putting around.

it will foul plugs and require a more skilled rider to

handle it in stock form. If u do end up modding it,

i would just make a throttle limiter for it so

if he accidentily hit a rock or got carried away,

it would only go to half throttle(and quite frankly,

for a less skilled rider, thats ALL ur gonna need)

Best regards,

jimmy

thanks for the advice.

what do you suggest??

I checked out the crf 150 but they are way to heavy

I dunno but the ttr 125 may get boring after a while.

pit bike ?? dunno again.

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thanks for the advice.

what do you suggest??

I checked out the crf 150 but they are way to heavy

I dunno but the ttr 125 may get boring after a while.

pit bike ?? dunno again.

Well, without knowing your son its hard to say. My son found his TT-R125 boring in less than a year (it was his first bike...). If all you are doing is putting around your yard or tight trails its fine but if you go to a track or open trails etc the YZ wins hands down.

My son trail rides his YZ85 about 50% of the time (we ride on trails on our property). It doesn't foul plugs (once you run the BR9EG in place of the BR10EG they come with) and he really has no trouble keeping it under control; but he has developed to me very good clutch/throttle control riding it. He is good at keeping it happily in the power band so it doesn't suddenly come on the pipe and scare him.

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Throttle stop YZ85, a brass ring installed between carb lid and slider:

Cnv0017.jpg

You can use whatever pipe, just be sure the throttle operates smoothly. Works perfect for a beginner rider, is easy to do and remove again when you think full power can be handled.

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I was basicly in the same position.. The yz85 was extremly intimidating.. First off, I would get a set of reeds.. I just got the Carbon Tech LT reeds because i'm low on cash, but Boyseen's would be a much better choice..

Second, go 2-3 teath up in the rear sprocket.. I went one, and I noticed a small diffrence. If i did it agian, I would probally go back and get 2-3 bigger in the rear sprocket..

After that, a flywheel weight would be a good idea untill he's more confident with the two-stroke power.

I actully got a FMF shorty too.. Honestly, it was a mistake.. Way too loud, and, the sprocket made a bigger diffrence, and was 70 bucks cheaper.. It didn't nessicarilly make a large diffrence eaither.

Good luck.

Why would you up the rear sprocket? That's going to make the bike accelerate faster and make the bike hit harder. That's not something I'd want for a beginning rider. We're trying to make the bike less intimidating.

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If you remove the cylinder and head and bring it to an engine tuner, they can pull the power back down low. Have them reshape the ports, and shave some thickness off the cyl head.

That should do it. Shouldn't be any more than $200, quite reasonable.

If you want it to tractor even more, like a CRF100/150, replace stock reeds w/ Boyensen RAD valve. Lower the pilot 3 sizes smaller, replace the stock NBKF triple taper needle w/ a straight taper needle, and lean out the main jet two sizes smaller.

With all that new found bottom end power, look at dropping your rear sprocket one or two teeth smaller. That will absolutely kill any midrange hit if present.

Jethro:

What single taper needle are you referring to? Do you know its code?

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imo you want to make the bike as torquey as posible because he will not use all that power up top why not sacrifise 5-15 mph top speed and make it low end by bumnping the front sprocket down a few teeth and the rear sprocket up a few teeth, then it should have so much low end power it could handle almost any obsacle, then to smooth that power out put in a sheahly offroad flywheel weight and it will be managable like a thumper and still have excelent low end power. then if you want to go one step further get a v force 3 reed assembly with reed petals and the cage. then your bike will be really snappy so he does not have to worry about climbing hills. then you have a bike with alot of bottom end and a manageable powerband to boot all this will cost you around 250$ not bad for what you get. hope this helps

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To make it easy, add a main jet three or four sizes too large. This will tone down the top end hit.

I have test rode several yz 85. At 205 I am not the perfect mini rider, but the power is very controllable. I bet your boy will be comfortable on this bike in three or four weekends. We give kids far too little credit for their abilities.

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