Yama Jama 20" in Neon Green- Mtbr.com
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  1. #1
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    Yama Jama 20" in Neon Green

    I am so stoked, after 6 weeks of research I finally pulled the trigger on a 20" bike for my 5 1/2 year old son: Yama Jama in Neon Green. This was a long process and I am relieved in a way, I was getting obsessed with this research and had to make a decision. I took me a lot less time to decide when I bought the last car that costs 60 times more .


    Attached Thumbnails Attached Thumbnails Yama Jama 20" in Neon Green-yama_jama_20_neongreen.jpg  


  2. #2
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    Sweet man. It's 10x better in person too. Wish my own bike was that color.

    You'll want to order a 40mm Wren stem too as it saves nearly a half pound on the front for like 40$. Stock one is kinda sucky. Maybe some carbon bars? It's a fantastic bike. Fwiw my 52lb 6yro runs about 70psi in the fork. You. Might try starting with 50psi and see if it bottoms out. Tires setup tubeless works well too. I'm not a fan of the brakes but my kid does fine with them. The piece that kind of sucks is that when you reduce the lever reach via the 2mm Allen key, the brakes have very little feel and then pull nearly to the bar. Maybe it works great for kids feel but I don't like it. I'd love to replace with something ultralight and powerful but I'm not sure what that might be yet. XT's are an obvious choice tho I'm a fan of something with more feedback for a kid hammer corners, if I'm spending the money.

    Cheers man! Go build some ramps now! 😀

  3. #3
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    Thanks for the advice!

  4. #4
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    Quote Originally Posted by Seb15 View Post
    I am so stoked, after 6 weeks of research I finally pulled the trigger on a 20" bike for my 5 1/2 year old son: Yama Jama in Neon Green. This was a long process and I am relieved in a way, I was getting obsessed with this research and had to make a decision. I took me a lot less time to decide when I bought the last car that costs 60 times more .
    LOL about the time spent relative to a car!

    What were the key deciding factors for you?

  5. #5
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    Quote Originally Posted by svinyard View Post
    Sweet man. It's 10x better in person too. Wish my own bike was that color.

    ...Tires setup tubeless works well too. ...

    Cheers man! Go build some ramps now! 
    Are the rims taped already or I have to tape them? Regarding ramps, already got couple of BMX ramps and we are practicing small jumps at this time .

    Quote Originally Posted by CeUnit View Post
    LOL about the time spent relative to a car!

    What were the key deciding factors for you?
    It all started when realizing that the 16" bike I purchased for my son in April has serious limitations on our root infested trails. Thus I started reading about 20" bikes and found this forum, the rest is history . ...but here is the rest of the story:

    In the beginning I was not going to spend this much on a 20" bike but reading on this forum I learned about chainstay length, the importance of a quality lightweight fork and the appropriate length of short cranks for a 5 year old kid.

    So I was set o get the Orbea MX Disk and buy a fork later on but while the geometry is good, the derailleur/cassette are kind of meh and the chainring is huge at 36T and cannot be easily upgraded without replacing the cranks and maybe even the BB. So by the time you are upgrading the derailleur/cassette and cranks/chainring and adding the cost of the fork it was getting up there close to $900.

    Another contender was Rocky Mountain Vertex 20 but that has the wrong sized cranks at 140 mm and quite a big bigger for a 5 year old while costing $700 + tax. In addtion, the 2018 model is no longer available and I could only get one transferred from another shop that was already build...

    I also looked at Prevelo Zulu Three, they are doing a major upgrade for next year but the bikes are not going to be available until late September and I was not going to wait that long. For those interested for Fall delivery, they are upgrading the frame to triple butted alloy for weight reduction and the fork will be a Suntor Air instead of Spinner for the same price as the current model. In addition, they are introducing an upscale model with an upgraded fork with carbon lowers and other upgrades but it was going to be even more expensive than the Yama Jama.

    In closing I am quoting myself from the Vertex 20 thread:

    1. First the tires are actually 1.9 on the 20" model, according to the Vertex web page and the Schwalbe site, there is no 2.1 in 20":
    Vertex Youth | Rocky Mountain Bicycles
    https://www.schwalbe.com/en/offroad-...lack-jack.html

    2. The price after tax for me is actually $757, once you add:
    a. $28 to replace the cassette with 11-36
    b. $75 shipped to replace the cranks with the Spawn 127 mm
    sub-totals to $860. If you want to get the Maxtion 2.20 tire that is another $85 shipped thus the cost of the bike and upgrades is $945. The Yama Jama is $1,090 shipped, in my mind there is no way I can justify going with the Vertex, here is why...

    I got my son earlier this year a Stampete Sprinter 16 thinking that I will not pay $380 for the Yoji only for one season. However, I already paid $250 bike + $38 riser bar + $10 alloy brake handles + $44 on real off road tires + $18 pedals I am at $360, I should have bought the Yoji and I am not making this mistake again.
    I was still going back and forth between the Orbea MX 20 Disk, Vertex 20 and Yama Jama 20 but I am pretty much decided on the Yama Jama now. I was comparing the geometry between the three and Yama Jama wins hands down against the Vertex and the Orbea MX 20 has too many negatives regarding gearing, chainring and components in general.

    Orbea MX 20 Disk | Vertex 20 | Yama Jama
    Chain stays: 343 | 360 | 340
    Wheelbase: 830 | 882 | 869
    HTA: 70 | 68 | 68
    TTL 445 | 460 | 450

    The only negative with the Yama Jama is that I will not be able to get good resale value in my area (Houston, Texas) once my son has outgrown it. Oh well, we spent thousands on stupid toys without any resale value, what is another thousand At least he'll get ~3 years out of it if we get it now at 5 1/2 years old.
    Cheers!

    --Sebis

  6. #6
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    The excitement is building up, we have a tracking number . Placed the order on Friday, got the tracking number on Monday with delivery ETA for Thursday (California to Texas in 3 days)! This was with the $40 the shipping option for those interested.

  7. #7
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    Quote Originally Posted by Seb15 View Post
    Are the rims taped already or I have to tape them?
    They come with everyday rim tape. You'll need to replace with Stan's tape or Gorilla tape, add universal valves, add sealant, and then you're good to roll!

  8. #8
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    Cool-blue Rhythm New Bike Day!

    A day late, FedEx Home Delivery took their sweet time and showed up only at 8 pm, I was waiting all day but kind of knew it is going to be a late delivery.

    By the time we were done with the assembly it was dark outside so no pictures but we had to go for a ride. We both got in trouble with Mommy since it is now after 10 pm and the kid is not in bed yet .

    Couple of points I wanted to make:
    - Tried to move up some of the spacers on the top of the stem, no luck due to the shape of the stem. @svinyard is right, the stock stem is kind of sucky, need to get that 40mm Wren stem to fix it, I could only move up the small (2 mm?) spacer.
    - The front brake caliper is not true, hope it is a non-issue after the break in.

    More feedback once we get a chance to ride it , still need to adjust the brakes reach and fork air pressure.
    Attached Thumbnails Attached Thumbnails Yama Jama 20" in Neon Green-img_1992.jpg  

    Last edited by Seb15; 07-18-2018 at 04:05 PM.

  9. #9
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    Ahhhh yeah. We are sleeping with this bike and mine tonight in hotel. It's race day at bike park on Sunday (Fwiw Steven's pass NW Cup that pinkbike covers). While we are out riding the bikes purpose here, it's still so capable. We definitely are outride some kids on 24 FS bikes up here (tho a lot of kids are so good and just fly on 20" FS bikes). Capable bike.

    Reach adjust is really close to the bar and it might not feel great to you, but my kid likes it and I have it setup for 1 finger braking. Seems to work great for him.

    Trueing that rotor should take 10mins with some nitrile gloves and a keen eye. Wheels are prob a bit out of true as well.

    Congrats!!!!!

  10. #10
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    Thanks @svinyard, are you participating in the race? If so good luck on Sunday.

    So today we went our for our first real ride, unfortunately it rained a lot in the past few days thus we had to stay on paved bike trails, maybe tomorrow will dry out a bit to get to our favorite riding place. Here in Texas, when it rains hard you better stay out of the trails. Can't wait for our first trip to Colorado to ride on some "real" trails .

    I was surprised how fast my son adjusted to the new bike being longer and heavier. He got out of the saddle right away and started pedaling, he loves it. I was tankful for the pivotal saddle, was able to lower the front to keep it parallel with the ground, out of the box was sticking up too much and was bothering my son.

    Random thoughts:
    - The dork disk has a terrible rattle and I am tempted to cut it out but concerned that it may be useful in the case of a crash. Any feedback on this is greatly appreciated.
    - The brake reach was not too bad to adjust, I set it up for two fingers at this point, my son doesn't have enough strength for one finger braking, yet.
    - I set up the fork to 50 PSI for now, my son is about 43 lbs geared up, need to play with it some more. Did you setup the sag like you would do for an adult?
    - Didn't have time for tubeless yet thus keeping air pressure at 55 PSI on paved trails.
    - The neon green color is sick in a good way, looks even more stunning in daylight.
    - The gear shifting at this point is not happening while moving, we have to stop, change the gear and start over again. I need to adjust the position of the lever to get more leverage, he just can't put enough force on that level to change the gear, hope will improve in time.

    In conclusion, we love the bike and are looking forward to the next ride!
    Last edited by Seb15; 07-18-2018 at 07:02 AM.

  11. #11
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    Quote Originally Posted by Seb15 View Post
    - The dork disk has a terrible rattle and I am tempted to cut it out but concerned that it may be useful in the case of a crash. Any feedback on this is greatly appreciated.
    I cut ours out right away. However, once in a while, after a fall where the rear 'der gets bent, the chain does get sucked into the spokes when shifting to granny and jams in there quite well. I still rather not have that disk in place.
    Quote Originally Posted by Seb15 View Post
    - I set up the fork to 50 PSI for now, my son is about 43 lbs geared up, need to play with it some more. Did you setup the sag like you would do for an adult?
    IIRC, I have 40 psi in our 100mm version of the Brood Eldorado. I set it up for ~30% sag.
    Quote Originally Posted by Seb15 View Post
    - Didn't have time for tubeless yet thus keeping air pressure at 55 PSI on paved trails.
    Wow that's a lot of pressure! When we had tubes I had my kid at about 25 PSI. Now that we're tubeless, I keep it at about 20 PSI.
    Quote Originally Posted by Seb15 View Post
    - The gear shifting at this point is not happening while moving, we have to stop, change the gear and start over again. I need to adjust the position of the lever to get more leverage, he just can't put enough force on that level to change the gear, hope will improve in time.
    Similar experience here. Took a couple weeks to figure it out at age 5. He started out by letting go of handle to grab the shifter and push it with his whole hand, but after a while, figured out the technique with just his thumb while riding. Good luck and have fun!

  12. #12
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    All good man. Cut the dork disk for sure. Haven't had any issues. Just get good at playing mechanic and follow old Calvin Johnsons advice. It's kept our chain out of spokes despite a thrashing.

    Dude I know it's cash but full face is such a good investment. Bell Super 2/3r is the ticket in small. My 3yr doesn't have one and an hour ago on pump track just thrashed his face and a little of one gum. Not good at all, hoping no one calls CPS on us. Brother wears the FF permanently but little brother doesn't. That may be changing very soon. Leavenworth pump track is very cool but damn that asphalt is hard

  13. #13
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    Quote Originally Posted by CeUnit View Post
    I cut ours out right away. However, once in a while, after a fall where the rear 'der gets bent, the chain does get sucked into the spokes when shifting to granny and jams in there quite well. I still rather not have that disk in place.

    IIRC, I have 40 psi in our 100mm version of the Brood Eldorado. I set it up for ~30% sag.
    Wow that's a lot of pressure! When we had tubes I had my kid at about 25 PSI. Now that we're tubeless, I keep it at about 20 PSI.
    Similar experience here. Took a couple weeks to figure it out at age 5. He started out by letting go of handle to grab the shifter and push it with his whole hand, but after a while, figured out the technique with just his thumb while riding. Good luck and have fun!
    Thank you @CeUnit, I just cut the dork disk and dropped the air pressure in the tires. I also adjusted the fork to about ~40 to 45 PSI, the display it's a little small and can't get that precise.

    Quote Originally Posted by svinyard View Post
    All good man. Cut the dork disk for sure. Haven't had any issues. Just get good at playing mechanic and follow old Calvin Johnsons advice. It's kept our chain out of spokes despite a thrashing.

    Dude I know it's cash but full face is such a good investment. Bell Super 2/3r is the ticket in small. My 3yr doesn't have one and an hour ago on pump track just thrashed his face and a little of one gum. Not good at all, hoping no one calls CPS on us. Brother wears the FF permanently but little brother doesn't. That may be changing very soon. Leavenworth pump track is very cool but damn that asphalt is hard
    Sorry to hear about the little one, hope we'll get over it quickly with no permanent marks. We all (the whole family) have full face helmet Bell Super 3r, see the picture at the top with the box. Unfortunately it is so hot & humid here in S/E Texas that can't force my son to wear it unless we do slalom or jumping the BMX ramp.

    Little ones are so prone to crashes and falls out of nowhere. This afternoon I was adjusting his brake levers for better reach in line with his arms and all of sudden he falls on one side with the bike on top of him while I was turning around to get a tool. Luckily he got just couple of bruises on his knees and didn't hit his head. No helmet since we were not riding, just sitting on the bike at stand still. Next time I'll get his body armor on even if we only wash the bike . So, good thing I took pictures this morning cause now the bike has "character" already after only one day, left pedal and both brake levers got some deep scratches from the drop on concrete.

    On the subject of adjusting the shifter, I rotated it so the buttons are facing up rather than forward, hope he'll have better leverage this way, see picture below.

    Yama Jama 20" in Neon Green-img_2009.jpg

    Cheers

    --Sebis
    Last edited by Seb15; 07-18-2018 at 07:07 AM.

  14. #14
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    Forgot to mention, Universal Cycles still has the Super 3R all sizes on sale for $160, not sure if the Small is not too big for your 3 year old:

    https://www.universalcycles.com/shop...s.php?id=83063

  15. #15
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    Quote Originally Posted by Seb15 View Post

    On the subject of adjusting the shifter, I rotated it so the buttons are facing up rather than forward, hope he'll have better leverage this way, see picture below.

    Click image for larger version. 

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    Coming back to report that changing the position of the shifter like in the picture above made a world of difference. Yesterday we had to stop to change gears, this morning my 5 year old was changing gears with no problem while riding. This one is solved! Highly recommend it to anyone having problems with reaching the gear levers.
    Last edited by Seb15; 07-18-2018 at 07:06 AM.

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    So I ordered the Wren 40mm stem (71g) and the Truvativ Noir T40 Carbon Flat Handlebar 31.8 x 580mm Blue (110g), they get delivered this weekend and can't wait to install them. Need to get a digital scale to measure and compute the weight savings per $ .

    Question for the more experienced parents, what else can I upgrade on the Yama Jama 20" for more weight savings that are not breaking the bank? I am doing tubeless next but other than that I am not sure that is anything else I can do.

    TIA

    --Sebis

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    Seb15, I’m in the processing of looking for a bike for our 5yr old daughter, and I know what you mean about getting obsessed with the research! I don’t suppose you ever looked into the Norco Storm 2.1 or Norco Charger 2.1?

    Our daughter currently has the Yoji 16in, and we’re about to get the 14” version for our son, so I really rate the Spawn bikes. We’re in New Zealand though, so by the time we get them shipped over and pay the local import tax the price quickly ramps up, where as we can by the Norco’s locally. Ideally I would get the Yama Jama also, but it will end up being about twice the price of the Norco.

    Just wondering how the Norco’s may compare to the Yama Jama, as it may work out better for us to just upgrade a few key parts and get a ‘similar’ bike for a bit less $$, but I am finding it hard to get weights for the Norco’s.

  18. #18
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    Quote Originally Posted by manamana View Post
    Seb15, I’m in the processing of looking for a bike for our 5yr old daughter, and I know what you mean about getting obsessed with the research! I don’t suppose you ever looked into the Norco Storm 2.1 or Norco Charger 2.1?
    I've researched the Charger 2.1 a lot and I'm a huge Spawn fan, but I must say unless you plan to ride true mountain bike trails, the Charger 2.1 is more than adequate. If you'll be mountain biking lots with your kids, I'd highly recommend the YJ esp since you have two kids who will use it (though they sound like they're close enough in age that there might be a year or so where you'll need two 20" bikes).

    The YJ offers better climbing gear ratio of 0.83 versus 1:1 on the Charger, but you can swap out the chainring on the Charger to improve its climbing gear ratio.

    The YJ's fork is waaaaay better than the Charger's, but the value's only there if you will be riding serious trails.

    At the end of the day, no matter which you buy, I'm pretty sure your daughter will be having a lot of fun. Good luck!

  19. #19
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    Sweet, just the sort of info I was after CeUnit! The bike will be used on trails, but realistically I don’t think our daughter will feel the difference between forks.

    The climbing ratio is interesting though, and something that could make a difference as there are lots of hills around here. I will look into changing the chainring if we get the Charger.

    The YJ definitely is a sweet bike though and would be my first choice if $$ wasn’t a factor.

  20. #20
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    We actually have two 20" Spawn bikes:

    1. Spawn Savage 2.0 (very very similar to Charger but slightly nicer - identical fork - almost identical geometry - same drivetrain as YJ) and it's fine for all the blue/green mountain bike trails we ride. Would be 'nicer' with a YJ given the better fork, but by no means necessary. Our friends who have the Charger 2.1 are fine on this terrain as well.

    2. Spawn Rokkusuta - Once we started riding the Whistler bike park where we're flying down blue/black mtn bike trails at mach speed and flying over big jumps and drops, that's when we truly ventured beyond the limits of the above bike/fork.

  21. #21
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    Quote Originally Posted by manamana View Post
    Seb15, I’m in the processing of looking for a bike for our 5yr old daughter, and I know what you mean about getting obsessed with the research! I don’t suppose you ever looked into the Norco Storm 2.1 or Norco Charger 2.1?

    Our daughter currently has the Yoji 16in, and we’re about to get the 14” version for our son, so I really rate the Spawn bikes. We’re in New Zealand though, so by the time we get them shipped over and pay the local import tax the price quickly ramps up, where as we can by the Norco’s locally. Ideally I would get the Yama Jama also, but it will end up being about twice the price of the Norco.

    Just wondering how the Norco’s may compare to the Yama Jama, as it may work out better for us to just upgrade a few key parts and get a ‘similar’ bike for a bit less $$, but I am finding it hard to get weights for the Norco’s.
    I looked closely at the Rocky Mountain Vertex 20 which is close in specs to Norco Charger 2.1 with better components for $50 more here in the US. Not sure if you can get that in the New Zealand. The issue with both Vertex 20 (and Charger 2.1) is that I wanted to shorten the pedals and upgrade the chainring/cassette and by the time I was accounting for these upgrades I was within $200 to the Yama Jama, you can see my calculations in one of the posts above. However, depending on your local prices it could make a lot more sense to by the Charger 2.1 and simply upgrade as needed. Good luck!

  22. #22
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    We made it to our local single track today, no more rain for the past few days. We had a blast except of one nasty fall due to a sandy pit, even with 20" wheels @ 25 PSI my son has trouble clearing those. Unfortunately he got a pedal strike on his leg and now The Boss ordered that I replace the pedals with a plastic variant instead of the metal pins found on the Wellgo pedals . There were also some words exchanged on the trail since of course it was my fault that he got hurt .

    So, any advice on lightweight pedals that are not too big for a 5 year old? I really like the Wellgo version that came with the Yama Jama but this is not a battle worth fighting .

    I should add, the 20" wheels and the Brood Eldorado fork made a huge difference comparing to his old bike with 16" wheels when negotiating those root infested trails. He got about 30 mm of travel without any jumps, just riding over the roots, the biggest drop was maybe 6". Was thinking that maybe I should drop the fork pressure a bit lower but he is already at about 40 PSI so I guess it will have to stay like this.

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    Bro. DO Not get freaking nylon pedals. Just get some Stroboli (sp?) soccer shin guards and cut out neoprene pads via a giant 7$ mouse pad. Those guards are great because they are super light and have padding around the ankle and calf, not just the front. Problem solved. It's dangerous for a kid to ride hard on real trails with crappy pedals that don't stick. Your kid will have more confidence too. Make sure he is using some Van's honeycomb shoes with the alloy pedals or some 510s. Shin strikes are nothing compared to full blown foot slips on a jump or drop.

    Also, you are way too high in pressure at 25. I run 15 up front and 18 or 20psi in back. If it's rocky and we are DH racing I'm running like 22 to avoid rock strikes on landings.

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    Thanks for the idea with the shin guards and lowering the PSI even further on the tires. I will go shopping for some shin guards today! You are right about the pedals, need to convince The Boss thou. We are good with the shoes, he is riding on 510s.

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    Quote Originally Posted by Seb15 View Post
    Thanks for the idea with the shin guards and lowering the PSI even further on the tires. I will go shopping for some shin guards today! You are right about the pedals, need to convince The Boss thou. We are good with the shoes, he is riding on 510s.
    There are the leg guards we use. They are also awesome for soccer too. Fyi they don't come with the guard insert for soccer. I made the neoprene one which I like much better that a full, hard soccer guard when biking. We wear the calf padding on the inside so when he crashes and the chainstay lands on his calf, there is some protection.

    https://www.amazon.com/Storelli-BSLG...rch&th=1&psc=1

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    Thanks for the link, I went shopping to our local sporting goods store and got some soccer socks with chin protection for cheap, it should do it for the type of riding we are doing now. I also stopped at the hardware store and got some M4 machine set screws and blue Loctite and replaced the OEM pins on the Wellgo pedals. These allow me to dial in the height and have as much grip if not more while looking less intimidating to Mommy .

  27. #27
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    Last night I installed the new carbon bar and Wren stem, don't know how much weight I saved but certainly feels lighter at the front. The Truvativ carbon bar feels high quality and I measured it at exactly 580 mm, ~8 mm shorter than the OEM Spawn bar listed at 560 mm, figure that, so no cutting was necessary.

    The Wren stem is crazy light, I was concerned at first, it almost looks too thin but feels as a quality piece, I trust the track record as shared on this forum . I torqued the stem using a fixed 5 Nm Park Tool wrench but stopped short before it skipped even thou the Truvativ manual said 5.6 Nm and on the bar is printed 6 Nm. I was thinking since my son is only ~40 lbs even 4 Nm or so should be enough, I did use a good amount or carbon friction paste.

    Here is the new cockpit.

    Yama Jama 20" in Neon Green-kamqbwqxsbocgth4yamjlq.jpg

    Quote Originally Posted by CeUnit View Post
    They come with everyday rim tape. You'll need to replace with Stan's tape or Gorilla tape, add universal valves, add sealant, and then you're good to roll!

    Next project is to go tubeless, the wheels are listed at 27 mm internal width, what size tape did you guys use?

  28. #28
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    Quote Originally Posted by Seb15 View Post
    Last night I installed the new carbon bar and Wren stem, don't know how much weight I saved but certainly feels lighter at the front
    Sounds great!

    I’m very interested in the weight saving you made so far. Do you have the possibility to weigh the stock bar?

    (Regarding the stem: From svinyard’s previous post (http://forums.mtbr.com/families-ridi...l#post13713014) the stock stem was 210 grams and Wren 70 grams, so -140 grams there!)

  29. #29
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    Quote Originally Posted by wallander View Post
    Sounds great!

    I’m very interested in the weight saving you made so far. Do you have the possibility to weigh the stock bar?

    (Regarding the stem: From svinyard’s previous post (http://forums.mtbr.com/families-ridi...l#post13713014) the stock stem was 210 grams and Wren 70 grams, so -140 grams there!)
    Unfortunately I don't have a kitchen scale, need to get one. I did weight the bike this morning on the bathroom scale after the changes were done, it came to 21.6 lbs, this is with pedals on and with tubes still on but my scale is +-0.2 lbs so it could be anywhere in between 21.8 or 21.4.

  30. #30
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    Rim tape - just use the same width they use on road or CX bikes. The narrow stuff. Just use 2oz of sealant instead of 3. But make sure you are diligent about topping it off every 3mos.

    Shin Guards + Five Ten Shoes make a gigantic difference for pedal contact. Vans or any other waffle bottom shoe at a minimum.

    G Form pads are the best out there for wearability.

    The mods on our YamaJamas 24's:


    • Tubeless
    • Ashima lightweight rotors
    • Stans Crest rims 1170gm wheelset with a bearing upgrade on the hubs.
    • Carbon bars
    • 28T chainring
    • The plastic cassette guard lasted 30 seconds before I removed it
    • Chromag Radar Pedals. We blew up the AEST Ti pedals in 60days. Lightweight is fine, but remember your kid is going to drop the bike onto the pedals often. I've trained my kids to lean the bike when parking. But frequent crashes will destroy featherweight pedals.
    • XT Bottom Bracket (original didn't last long and good bearings are priceless) It's approximately 1000% smoother than stock. <- scientific fact.
    • Carbon side loader bottle cage


    You could re-lace those wheels with Sapim CX Rays and do some lighter hubs with better bearings. Probably good for at least .5lb.

    Wren stem is next for us.
    Extra slippery shifter cable is coming soon. They can operate the shifters fine. But a slick cable will help.

    Go and order 2 derailleur hangers from Spawn. You will need them.

    I'm close to ordering an Abbey Bike Tools HAG. If that give you any idea of my frustration level with bent hangers. For my birthday last week, I got a ton of bike tools. And honestly, I already owned a lot of bike tools.

  31. #31
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    Thanks for the ideas to lower the weight, once we get out of the heat advisories I'll get going with the tubeless conversion and I think I'll stop there for a while.

    Today we did our first real trail riding with the upgraded cockpit, drove early in the morning to a state park about 40 minutes away. Great trails and we did great on descends, I was afraid he was going to crash. Lots drop-outs caused by roots, some were 10" or so but he did great, the fork did its duty and slacker geometry helped for sure. Going back uphill was not as fun thou, I knew he can't pedal uphill on that trail and we took the nearby park road but still had push two bikes for the last half mile.

    How do I get him to develop his strength at 5 1/2? Any tips form the parents?

    Yama Jama 20&quot; in Neon Green-img_6485.jpg

    TIA

    Sebis
    Last edited by Seb15; 07-29-2018 at 03:57 PM.

  32. #32
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    Quote Originally Posted by Seb15 View Post
    Thanks for the ideas to lower the weight, once we get out of the heat advisories I'll get going with the tubeless conversion and I think I'll stop there for a while.

    Today we did our first real trail riding with the upgraded cockpit, drove early in the morning to a state park about 40 minutes away. Great trails and we did great on descends, I was afraid he was going to crash. Lots drop-outs caused by roots, some were 10" or so but he did great, the fork did its duty and slacker geometry helped for sure. Going back uphill was not as fun thou, I knew he can't pedal uphill on that trail and we took the nearby park road but still had push two bikes for the last half mile.

    How do I get him to develop his strength at 5 1/2? Any tips form the parents?

    Click image for larger version. 

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    TIA

    Sebis
    Yama Jama 20&quot; in Neon Green-pivot-5.7.jpg

    Tow rope (3m retractable dog leash zipped tied under seat, 1ft bungee cord with carabiners on the Yama Jama)

  33. #33
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    Thank you!

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    Quote Originally Posted by deus_ex71 View Post

    Tow rope (3m retractable dog leash zipped tied under seat, 1ft bungee cord with carabiners on the Yama Jama)
    I just ordered a towwhee to lead my kids around the trails in Santa Cruz. Might be a safer choice than the dog leash solution.

    www.towwhee.com

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    Quote Originally Posted by SantaCruzBradley View Post
    I just ordered a towwhee to lead my kids around the trails in Santa Cruz. Might be a safer choice than the dog leash solution.

    www.towwhee.com
    He said he's got some bungee on the kid's bike. But, yeah, I towed my kid up tons of stuff at that age with a DIY version of the Towwhee and you definitely want some decent "suspension" in your tow device. Works great though! The main thing to be mindful of is short grade reversals as they can create a bit of a slingshot effect. Also, take turns wide, like towing a trailer driving. There's a bit of a learning curve, but we got it dialed in pretty quick and could negotiate tight switchbacks like it was no thing.

  36. #36
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    Quote Originally Posted by CeUnit View Post
    Wow that's a lot of pressure! When we had tubes I had my kid at about 25 PSI.
    I second that. Once you go tubeless, you could run a lot less. My 6yo daughter has 20" Brood Maxtion tires, set up tubeless on the stock rims of her Orbea MX20. She's very petite for her age (about 35lbs) and we're running about 8 psi on her tires. Lots of grip on rough trails, and she has yet to burp any sealant. Heck, I'm 185 lbs. and I run 15 rear 14 front (although I'm running 2.6 tires on i35 rims). Even with tubes, if your kid isn't charging through gnarly rock gardens, you can get away with 10 psi or so.

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    Thanks, we still have tubes but running about 18 PSI now.

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    For strength development. The tow rope is a great idea for his age. It would allow you to ride a bit longer for sure. If you can get him on a bike 3x a week. Like 1 trail ride per week + a couple neighborhood rides. For even a couple weeks, you will see a gigantic increase in his strength. Kids have super powers man. They gain fitness very quickly. Also, just getting the ergonomics right on the bike with the shifters and brake levers along with teaching him how to shift will yield a big pickup in efficiency.

    I am very careful about measuring the efforts of our rides and bring plenty of snacks and planned breaks. I mapped out 3mi, 4, 6, 9, 12mi rides in progression over a few months. Nothing worse than a kid totally melting down, completely exhausted and a danger to themselves on downhills. And they can get turned off real quick if every time they ride means riding beyond exhaustion. Have fun!

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    I wouldn't worry about it man. Endurance is of very little importance at this time. Real bike skills are so much more critical and fun too. Find what's fun and do a LOT OF IT. Shuttles are well worth the investment. Think of it like skiing. No one is teaching their kids to rip via cross country skiing. Too boring and hard for littles.

    Id also start to find a mtb team the kids can join. Coaching your own kid at anything has its limits.

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    Thanks for the feedback, I ordered the TowWhee.

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    Quote Originally Posted by Seb15 View Post
    Thanks for the feedback, I ordered the TowWhee.
    I ordered mine on Saturday; shipped today. Can't wait to take the kids out with it!

  42. #42
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    Quote Originally Posted by Seb15 View Post
    So I ordered the Wren 40mm stem (71g) and the Truvativ Noir T40 Carbon Flat Handlebar 31.8 x 580mm Blue (110g), they get delivered this weekend and can't wait to install them. Need to get a digital scale to measure and compute the weight savings per $ .

    Question for the more experienced parents, what else can I upgrade on the Yama Jama 20" for more weight savings that are not breaking the bank? I am doing tubeless next but other than that I am not sure that is anything else I can do.

    TIA

    --Sebis
    The difference between a 1030 11-36 and an old XX 1099 11-32 cassette was 201 grams. I was lucky, had one in the parts bin. There's one on ebay right now that's an 11-36 for $130 or so.

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    I know it's an old thread but for strength bmx racing is really good and a ton of fun to boot.

    For saving weight it's tough to tell as spawn doesn't list enough detail about their components to really figure out where the fat is. I'm guessing the wheels, cassette, and bb (if yours is square taper) are quite heavy. Cassettes carry wildly in weight. The one we are using is 136g (7spd x01). Some are over a pound! Same can be true of hubs and freewheels to some extent. Cheaper ones are often around 400g and good ones around 200 (rear only).

    Sent from my Pixel 2 using Tapatalk

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