2019 Yamaha YZ65/85 24 Hour Torture Test

At Keefer Inc. Testing we pride ourselves on riding the crap out of our test bikes. However, when it comes to smaller bikes, it’s not like I can Benjamin Button myself and ride 65’s/85’s. 1990 West Coast 125 Supercross Champion Ty Davis put together a Jr. 24 Hour Challenge Team for the 24 Hours Of Glen Helen that focuses on the younger generation of off-road racing. We need to keep kids on dirt bikes to help grow our sport and Ty has been working hard to make this happen. Dustyn Davis (son of Ty) has our 2019 YZ65 test bike, so we thought why not let him and his buddies loose on this sucker for the full 24 hours as a durability test so to speak. While those kids were at it why not have another batch of kids on our 2019 YZ85 as well. Our goal was to get the kids away from FortNite and get more riding time in, while getting some quality testing information downloaded as well. It’s a win, win! No PlayStation’s and XBOX’s here people! Below are the modifications that were performed to the 2019 Yamaha YZ65/85 and the outcome of each machine, directly from ZipTy’s team. -KK



2019 Yamaha YZ85

1. Put IMS footpegs on (wider) to help the kids feet, spreads the pressure more evenly so they don’t get sore over a long period of time

2. G2 Aluminum Throttle tube- due to kids falling, more reliable than the stock plastic.

3. Cut Bars- for kids to have better control of the bike and handle better

4. Pro-Taper bendable levers foldable to eliminate the levers from breaking if kids fell

5. Dirt Tricks Spokes for reliability and longevity

6. DID Chain for durability

7. Rekluse Manual Clutch- For reliability

8. Steahly Stator with lighting coil for the lights

9. Galfer Custom Brake line made to clear the lights

10. Uni Air Filter

11. Mousse front and rear to eliminate flats less tire changes

12. Maxxis Tires

13. VP Fuel 110 mixed 50/50

14. IMS oversized tanks for less pit stops

15. Seal Savers to keep mud out of seals

16. Baja Designs Lights for lights at night

17. Zip-Ty Custom made light brackets

18. Zip-Ty Coolant to keep the bike from overheating with muddy conditions

How It Performed:

The 2019 YZ85 survived the full 24 hours in the muddy and rainy conditions without any issues. The Yamaha handled well in the tight technical sections and was easy for the kids to maneuver. We had a wide range of riders who race NHHA, Motocross, Big 6, and WORCS. The only problem we encountered was that the kids we used were not tall enough for the YZ85. In order to get them more comfortable, we cut the bars down 5mm and took a little preload out to lower the rear of the bike. This helped get kids to touch their feet in tighter sections of the trail. The kids liked the performance of the engine as it was exciting off the bottom, but not too pipey where it wasn’t connected to the rear wheel in the slippery conditions. The engine character was aggressive enough for the more experienced kids, but easy enough to ride for the novice kids that we used. The suspension was a little stiff (even when adjusters were backed out) for the kids on small chop because all the testers were smaller in size (70-100 pounds). We knew the Yamaha was known for its durability, but this race proved it, even with five different style of riders.

The 2019 YZ85 made it 43 laps that equaled 344 miles and finished 23rd out of 38 teams.

2019 Yamaha YZ65:

1. Customized seat for easier access for air filter changes

2. Galfer Custom Brake line made to clear the lights

3. DID Chain for durability

4. Uni Air Filter

5. Vortex Sprockets

6. Mousse front and rear to eliminate flats less tire changes

7. Rekluse Manual Clutch- For reliability

8. Maxxis Tires

9. VP Fuel 110 mixed 50/50

10. Seal Savers to keep mud out of seals

11. Baja Designs Lights for lights

12. Zip-Ty Custom made light brackets

13. Zip-Ty Coolant to keep the bike from overheating with muddy conditions

14. Put IMS footpegs on (wider) to help the kids feet, spreads the pressure more evenly so they don’t get sore over a long period of time

15. G2 Aluminum Throttle tube- due to kids falling, more reliable than the stock plastic.

16. Cut Bars- for kids to have better control of the bike and handle better

17. DID Chain for durability

18. Pro-Taper bendable levers foldable to eliminate the levers from breaking if kids fell

19. Millenium Re-nickelsil the Cylinder for durability

20. AME Half waffle for the Kids hands Super glued on

21. Shock Spring one rate softer, Pushed the forks down in clamp 3mm for stability

How It Performed:

We ended up changing the front and rear brake pads once, air filter once, one rear wheel, and poured in 20 gallons of fuel. The team had to replace the stator back to stock due to a failure that made the bike cut out/misfire. Once stock stator was installed we had zero issues. Each tester loved the power and all said that they were able to keep up with the 85 team for most of the race. Why? Because the Yamaha YZ65 engine is powerful enough and can keep up with the 85 in the tighter sections of the course. With the race being so muddy this slowed the overall speed down, which helped the 65 team. The Yamaha YZ65 suspension was plush enough for the 65 team and all of the kids thought it provided enough comfort, even with several pounds of mud packed on the machine. The Yamaha YZ65 finished the event with 43 laps that equaled 344 miles and finished 24th overall out of 38 teams. With Yamaha introducing the 2019 YZ65 this year, it proves that this first year model is a reliable bike for the little ones.

2019 Yamaha YZ65

1. Customized seat for easier access for air filter changes

2. Galfer Custom Brake line made to clear the lights

3. DID Chain for durability

4. Uni Air Filter

5. Vortex Sprockets

6. Mousse Tubes front and rear to eliminate flats/less tire changes

7. Rekluse Manual Clutch- For reliability

8. Maxxis Tires

9. VP Fuel 110 mixed 50/50

10. Seal Savers to keep mud out of seals

11. Baja Designs Lights for lights

12. Zip-Ty Custom made light brackets

13. Zip-Ty Coolant to keep the bike from overheating with muddy conditions

14. Put IMS footpegs on (wider) to help the kids feet, spreads the pressure more evenly so they don’t get sore over a long period of time

15. G2 Aluminum Throttle tube- due to kids falling, more reliable than the stock plastic.

16. Cut Bars- for kids to have better control of the bike and handle better

17. DID Chain for durability

18. Pro-Taper bendable levers foldable to eliminate the levers from breaking if kids fell

19. Millenium Re-nickelsil Cylinder for durability

20. AME Half waffle for kids hands that were super glued on

21. Shock Spring one rate softer, pushed the forks down 3mm

How Did It Perform?

Changed brake pads once, air filter once, one rear wheel, and 20 Gallons of fuel. Had to replace the stator back to stock due to a failed custom stator.  Kids thought the power was fast, yet easy to ride hard as they were able to keep up with the 85 team for most of the race. The suspension seemed to be more forgiving on the Yamaha YZ65 as the kids never complained once about anything suspension/chassis related. The 65 team had a wide range of talent that ranged from motocross to off-road and each of them performed well for the 24 Hour long haul.  The Yamaha YZ65 team did 43 laps that equaled 344 miles and finished 24th overall out of 38 teams

The 65 team picked the Yamaha because Dustyn Davis (son of Ty Davis) raced it all year and we wanted to prove that the Yamaha could withstand 24 hours of kids beating the shit out of it. This raced proved that there is superb durability for a first year 65cc model from Yamaha.

2019 Yamaha YZ85 Review

When I heard Yamaha was coming out with a new YZ85 in 2019, I wanted to task my son with the job of writing the review. As a test rider I come in contact with a lot of new bikes, parts, etc., but I really wanted my son to know that all of this doesn't come without a cost. There is work to be done once I get these machines. This isn’t a free for all and he doesn't get free bikes just to thrash/ride. I wanted to keep this test/review as is and only clean up some grammar errors for reading purposes. I wanted to make sure this article was as good for your kids to read as it is for you, the parent, that may be in the market to  purchase a new 2019 Yamaha YZ85. I want to keep our kids on dirt bikes and not on their Playstation’s playing FortNite all day. Without further adieu here is Aden. -Kris Keefer

Aden Keefer and the 2019 Yamaha YZ85

Hi everyone, my name is Aden Keefer, I am 5’0, weigh 84 pounds, have red hair and I like to ride dirt bikes. My dad has been helping me with how to feel out a motorcycle when I go ride for the past couple years, so I thought I would give writing a review a shot. I have ridden a 2018 KX85 and 2018 YZ85 in the past, so in this article I will go back and forth and compare the 2019 Yamaha YZ85 a little between the other two bikes I have ridden. Riding dirt bikes with my dad is more fun than playing Fort Nite on my Playstation (editors note; but that doesn't stop him from wanting these things called “V-Bucks” all the time for that damn game), but now I have to do some work and write about it. My dad keeps telling me nothing in life is for free and now I know what he means. I hope you enjoy my article and get to learn something about this cool new 85 by Yamaha.  

Some of the highlights of the new 2019 YZ85 that caught my eye are the 85cc 2-stroke engine has a YPVS (Yamaha power valve system) that boosts low and mid range power, a 36mm KYB coil spring fork, an updated shock setting, new aluminum swingarm, new routing on the front brake hose, wave style brake rotors and dunlop MX3S tires. When my dad showed me all of this it got me excited because I like riding 85’s that have a powervalve more because it always made me ride smoother, which from what my dad tells me, makes me ride faster. I guess I will trust his judgment since he is so old, sorry dad. 

Here are some of the other key details of the 2019 Yamaha YZ85 that Yamaha sent us that I need to tell you about: Yamaha makes the 2019 YZ85 better by creating adjustability for growing riders as the YZ85 comes with a 4-position adjustable bar mount, with 1-1/8 aluminum Pro-Taper style handlebars and adjustable front brake/clutch levers. Yamaha’s 85cc 2-stroke engine with YPVS (Yamaha power valve system) boosts low to mid-range power with strong high-RPM power. The mechanically controlled dual valves begin to open at 8,500 and fully open at 9,000 rpm. The valve open compression increases from 8.1:1 to 8.2:1 and the valve closed compression is 9.6:1. The connecting rod is 4mm shorter with a resin balance weight added, the crankshaft oil seal ID is reduced 8mm, there is a revised crankcase shape to optimize charge flow as the primary compression ratio is increased. On the carb side of things the Keihin PW28 carburetor has some new settings with a new high-flow spacer-style reed block and high tension reed pedals,(0.42 to 0.52mm). There are new expansion chamber dimensions, a revised CDI mapping, a new higher voltage coil, new water pump housing and exit pipe, a wider base on 3rd and 4th gears that is claimed to increase gear strength and help with smoother shifting. There is a rear sprocket change from 47 to 46, a new 36mm KYB coil spring fork and shock settings, the new 36mm KYB spring front fork has a high rigid one piece outer tube, new aluminum swingarm, new front brake hose and wave style discs, new Dunlop MX3S tires, new chain adjuster, chain guide, the front brake has a more direct brake hose routing with wave style front and rear discs, updated fork guards, an oversized 1-1/8 aluminum taper style handlebar with new 4 position adjustable bar mounts and finally adjustable reach clutch and brake levers. As you can see there are tons of changes to this bike and it was tough for me to get all of them in there, but hopefully I got them all in. 

Engine: The Engine on the 2019 Yamaha YZ 85 is very strong coming out of corners, but doesn't pull my arms off the bars like my 2018 YZ85 did once it hit the powerband. My Kawasaki KX85 kind of takes a while for the power to pick up in corners and is easy to manage, but feels slightly slower off the bottom compared to the new YZ85. I have been racing the AME Minicross Series at Milestone that is basically a tamed down SX track for kids and is very fun. When I come out of the bowl corners on my 2018 KX85 it doesn't really have the pulling power as much as my 2019 YZ 85 does. The 2018 YZ 85 doesn't have the top end that the new 2019 YZ 85 has because I can jump longer tabletops easier, which makes my mom nervous. My dad can usually calm her down a little, but when she is nervous she doesn't talk. With the 2018 YZ85 I had to fan the clutch a lot through the corners, but the 2019 Yamaha YZ85, I can stay off the clutch more and that makes my dad happy. He told me once when we were at the track that he doesn't want to raise an Alex Ray. I don’t know what he means by that, but I like Alex, he's my buddy (editors note; Alex is a nice guy, but Yamaha doesn't have enough clutches in the world to help my kid if he fans a clutch like A-Ray does). What I really like about the new YZ85 is that it takes less work for me to ride fast. I don’t get as tired on the 2019, like I did with the 2018. I am able to go through corners in second gear instead of having to downshift to first. This makes me smile. 

Suspension: The 2019 Yamaha YZ 85’s suspension has a firm feel to it with excellent hold up. My dad told me to use the word “hold up” if it was firmer, so I just did. We had Race Tech re-valve my suspension on the Kawasaki KX85 and it was stiff, but that was very useful because I sometimes case jumps. The 2019 YZ85 suspension is similar to my Race Tech stuff because it doesn't react that quick and feels like it has more of a slower feel to it. I also notice that in braking bumps the Yamaha YZ85 doesn't move that much and sticks to the ground better than my last year’s Yamaha. The 2018 Yamaha moved a little more in the stroke when I hit bigger bumps, especially at Glen Helen. Last year’s YZ 85 suspension was too soft for me and it hurt my wrists at times when I landed. If I hit a large jump on the 2018 YZ85 the suspension would bottom out. However, on the 2019 YZ 85, the suspension is much better stock and I feel like I have more comfort on landings than I had on my previous year’s bike. I get more confidence with the 2019 YZ85 and that let’s me try to ride faster. I keep telling my mom and dad that I can go faster now, but they keep telling me to take my time (editors note; yes he is right, I have to pump the brakes on his “send it” button).  

Chassis: The chassis on the 2019 YZ 85 is stable when I am hauling down straights, but can give me head shake a little at times on square edge, choppy tracks. My dad softened the compression a little and it felt better on rough track days. I really like the way the 2019 YZ85 corners and to me feels lighter than last year’s bike. The 2018 YZ 85 is a hand full for me at times because it can be hard to lean over as I start to get into the middle of the corner. On my Kawasaki KX85 I felt like it cornered good and it hooked up, but felt big when the track was rutty. When I rode rutted tracks the green bike felt long and sometimes it was tough for me to line up in a rut. The 2019 YZ85 feels compact and I am able to put the bike into ruts better. I really like the way the rear pivots in bowl corners because it whips around quickly. I also love the new handlebar! The oversize crossbar-less bar fits me just great. I didn't move the position and left it stock as it fits me just fine for right now. When I grow I will be able to move he bar mounts forward to help me move around on the bike more.

My overall opinion is that the 2019 Yamaha YZ 85 is a really good bike and I enjoy it a lot. I love railing corners on this bike and hitting some bigger jumps, if my dad lets me. :( I like this bike more than the 2018 Yamaha YZ85 because it is faster and handles better to me. I look forward to ripping it up out there in the future with this bike and having fun. This has been Aden Keefer and I hope you liked my article. Go Check out KeeferInctesting.com and click on “Podcasts” so you can listen to. my dad and I talk more about the 2019 Yamaha YZ 85.

2018 Yamaha YZ85 Review

KEEP KIDS ON DIRT BIKES NOT THEIR PHONES!!! It's known that kids are the future of the world, and what better way to raise those kids than on a dirt bike right? The 2018 YZ85 brings big-bike performance to a small package, all for $4,299 of mom and dad’s hard earned blue collar money. The Yamaha has 33-inch seat height and 157-pound overall weight so make sure your little guy or gal has some biceps on them. The YZ 85 package may not be small, but depending on what your kid is looking for, may be the perfect amount of punch to haul them around the track or trail. My 12 year old son Aden is a novice moto kid, is 81 pounds, 5'0 tall and loves dirt bikes. He has been riding gas powered dirt bikes since he was eight years old and has put a ton of hours on the the Yamaha YZ85 over the course of several months.

The YZ package has been around since 2002, but the bike got a clutch and transmission update in 2014 and then a new cylinder, bodywork, and clutch lever in 2015. The Yamaha is the only two-stroke that does not have a power valve, which shows up in less-broad power.

The Yamaha’s engine has somewhat of a weak low-end, but once into the power the blue bike pulls hard. This can be a problem for beginner or novice type riders as there is really no smooth transition from bottom to mid range.The Yamaha needs more clutch effort out of corners to get up in the revs and more shifting to stay in the mid and top-end, but Aden said that once he was in the middle to upper range the bike was fun. It was the low end that was difficult to manage at times for him, especially when he got tired. Jetting is slightly rich off bottom in stock trim, which can be ok for slower riders to help make that sudden “hit” less intimidating, but we raised the clip portion up one to clean some of that bottom end up. Aden found the shifting was smooth and I never viewed him missing shifts or hitting false neutrals while trying to pin it around the track.

Aden Keefer's butt whip

The fork and shock soaked up bumps for my 81 pound red head and seemed to work great in both high and low-speed tracks we ride at. Aden described the suspension as like pillows over bumps. I kept an o-ring around the fork to see how much travel he was using to monitor if I needed to stiffen or soften the compression on the fork. Upon inspection, we kept the forks clickers stock and overall the suspension looked to have a very dead feeling when Aden rode it. Interesting note with the suspension: I tried making some changes to the fork to see if Aden could feel the difference, but he usually came back with “ I don’t feel anything”, so I went with what I saw on the track and left the fork alone. Aden praised the YZ’s cornering ability and thought it was very nimble (despite the weight on paper) when practicing his butt whips over some kickers. Straight line stability is superb on the Yamaha under acceleration and braking bumps. Aden never really was out of control on the YZ85, but dad also gets on him about being safe, so make sure to reiterate that to your child as well. Aden did complain about the brakes being somewhat soft/spongy when we picked up the Yamaha, so we bled both ends and that gave a better feeling around the track. The overall feeling of the YZ85 is a low and compact machine when riding and inspires confidence to try new things on the track. Aden liked his sag set at 84mm as that left him with a balanced feel around most tracks. This is more of a preference thing, but a good rule of thumb is to keep the 2018 YZ85 at around 80-85mm of sag. The cockpit is roomy that seems to be meant for taller kids and wasn’t  cramped for the 5’0 length of Aden. 

The durability of the 2018 YZ85 is superb just like its bigger blue counter parts, but the clutch is one thing to watch out for. As Aden started to get a little more aggressive with the clutch, the lifespan of the plates went downhill. I changed out a clutch twice in a matter of 15 engine hours, so make sure to listen to your kid while riding to see if you can hear it slipping. Hinson and GYTR make clutch kits for the YZ85 that is stronger than stock and will last longer for your child’s clutch happy finger. Besides a clutch all we did was change air filters, transmission oil, grips and tires for the 35 hours that we have had the YZ85. The little blue ripper is a reliable piece of machinery for any young child to have fun on.   

Extra Credit: We installed GYTR’s pipe and silencer combo on the 2018 YZ85 to see what it does to the power curve. Installing this pipe and silencer combo actually smoothed out the power down low (less of a light switch feel), but increased the mid to top end pulling power. In order to test this out dad had to get his 170 pound butt on the seat and do it himself, but I was able to feel the power character change immediately. If you are looking to smooth out the low end feel of the Yamaha’s power valve-less engine, the GYTR pipe and silencer could be a great choice. You can check out all of Yamaha's hard parts over at shopyamaha.com or visit Yamahamotorsports.com.

Extra Extra Credit: We also tried a out a Bills pipe and silencer on the 2018 YZ85 to see how it compared to the GYTR version. The Bills pipe and silencer combo is a more race oriented package with more of a hit. If you're looking for more bark down low and crisper throttle response, the Bill's combo does just that. Bottom to mid RPM response was increased and the bike sounded like a miniature 125! It barked! However, it didn't rev out quite as good as the GYTR version on top end. Mid-top end performance was slightly better with the GYTR pipe/silencer, but Aden liked the looks of the cone pipe on the Bill's better than the GYTR. Kids these days, I wonder where he got that? You can visit billspipes.com to check out the Yamaha YZ85 cone pipe/silencer. 

If you have any questions about the 2018 Yamaha YZ85 feel free to email me at kris@keeferinctesting.com