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2017 Superhero Builds Yamaha's YZ450FX and YZ250

I am interested on how the crank holds up at the high rpm with the extra weight of the piston...

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Things rode well all season and did not come apart. We will know more on a case split inspection in the next month.
 
Was it a big upgrade in the ridability in the powder? Pulling gears?

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When a customer wants us to set up their bike, and that set up includes a front sag set up. We spend over 2 hours tearing down forks and working with springs and shims to get the front fork sag set correctly. It is a fine line between proper spring length and shim spacing. If you use to many spacers the spring will coil bind. Sag is the first and most important setting on a snow MX suspension!!!!! Every other setting is based off the front end sag.

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Now that Wonder Woman is complete, it is time to ride!!!

The one of the first rides out was at a National MX race. The coarse had a big up hill pull that separated the power from the stock. I could be 4 bike lengths behind a stock YZ450FX / Camso with a 30lb heaver rider out of the bottom corner and catch him by the top of the climb. This bike has some serious grunt and torq off the bottom end and mid.

After that it was all tree duty all season for the WW. It is so light weight, feeling of being flickable in the trees is a riot to ride. The Yeti 120 track was a perfect pairing to this bike to add a nimble feeling and light weight. I feel that every two stroke ( except 500's ) should run a 120 or 129 SS Yeti. The way this light weight system with the belt drive responds to the 2-stroke power delivery are some of the best combos on the snow.

Wonder Woman makes an awesome ladies bike. She is so light and easy to ride and it pulls almost any gear. She will get out of a tricky spot with ease and not need clutch feathering to do it. I had her out on many family days and the ladies found her easier to ride than most of the 4 strokes.

There were no motor issues all season other than a self induced over heat. We had a big day on the fresh 2' fresh powder and had the prefilter screens over the radiator guards to keep the massive ice build up off the front of the bike, but forgot to pull them back when we hit the groomed trail to go back to the parking area. The rider was not watching the temp guage and at 262deg. the piston seized in the bore and he pulled over. It started right back up and rode hurt for the next few weekends, but it survived all scored up. I had ERS shipp me a new set up so I would have extras. On the last ride it started blubbering in the low to mid with very cool EGT's but spot on 1150deg. on the top hard pulls. I have not done the tear down, but I think I may have broken a reed.

We were able to start her with ease all season, all the way down to -10deg. and only had to splash a little fuel on the air prefilter a few times. We ran 91 octane with Amsoil at 50;1 all season. Our jetting never needed to be changed, and the carb heater worked so well, we never even thought about carb-icing. Our hands did get a little cold and we had to wear elephant ears more days than we liked. Be cautious, we went to ride one morning and there was enough condensation water build up in the gear box to freeze solid and not allow us to put the bike in any gear until it warmed up. This happened one of our first rides out, before our first oil change. It may have been there from shipping???? It did cause a slight bend of the shift fork. Making the 2-1 shift a pain. We never had it happen again throughout the season.

The motor pulls so hard and is a super grunt kind of ride. I loved it and could ride it hard, but I did feel that it was lazy and not the snow bike fun I was after. Very similar to the 660 Berg I built. I think that the bore may be a little large and does not give the free revving pull I am looking for. For the 2018 season I will be trying the Yamaha GYTR 300 kit and Raze heated bars on this bike. I think the 300 and its faster revving piston will be the perfect marriage between low end grunt and free revving snow bike fun.

Keep in mind I am not building Super Bikes to go and just run. I am building Super Bikes to find the ULTIMATE in snow bike FUN. I want: throttle wacking, bouncing off the rev limiter, drift popping, branches sticking out of your helmet, face bleeding, hair on fire, kind of snow bike fun!!!!! :face-icon-small-ton:face-icon-small-ton:face-icon-small-ton:face-icon-small-ton:face-icon-small-ton:face-icon-small-ton:face-icon-small-ton:face-icon-small-ton:face-icon-small-ton





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We now move on to the stock builds:

Hulk and Thore

They both are stock 2017 Yamaha YZ450FX's. Once again we chose this platform for it's reliability and ease of use for people to jump on and ride easily, with out having to kick start a bike. Yamaha's once again proved to be the ultimate in reliability for this season. The electric start worked well and never let us down in the back country. We always carried a jump pack, but never used it. We did not have to do anything but change the oil!!!!

Hulk got fitted with a CMX BK129 and Thore was fitted with a Camso DTS 129.

Both bikes got all of the recomended RMS MX accessories:

ProMoto Billet: Screw in bar ends, Fit1 hand guards, Billet handle bar risers, and Adventure foot pegs with the F6 cleats.
( The bar risers will help get your body position into the correct placemnt by getting you up and back on the bike trying to counter act the weight of the kit on the back. The Fit1 hand guards with the full top clamp will keep your bars and risers straight when you hit a tree hard or your bike falls over int he parking lot. The screw in tapped bar ends will lock the bark busters to the bars and not let them move. I hate having to straighten out my bark busters when my bike falls over in the parking lot. With this system most of the time they will not move. The Adventure foot pegs are wider than the stock units and allow you to have the pegs under the center of your boots and not be pigeon toed because your heals are out further to avoid the added width of the kit. )

AME heated electric grips
( They are about the same diameter of stock grips so you do not get arm pump and the heating element is built into the grip so it will not turn on the bars. They are 7 way adjustable and have a single switch for ease of installation. )

Trail Tech temperature gauge
( these units are battery powered and go right into the side of the thermobob. No need for extra wiring. )

RMS MX custom front fork springs and valving
( The KYB forks in the Yamaha's are the best forks to use in the snow bike industry. We can custom wind springs for your application and you will be about 80% of perfect. We can also do custom snow bike valving to your forks and give you a front end has full adjustment levels on both compression and rebound to achieve the 100% perfiect front end matched to your rider weight, gear, and kit. We also build custom forks for you KTM guys struggling with 4CS, and AER. )

GYTR slip on exhaust

Yamaha GYTR electric fan
( The fan kit is so easy to install and helps on the warm days so you do not have to keep the eagle eye on temperatures when you are working it hard. )

Bullet Proof Designs radiator guards
( Their design both protect the radiators from being crushed in a tip over, but they keep the trees from poking through the fragile radiator fins. They also act like a large heat sink and do not collect the amount of ice on the front of the radiators like the stock plastic fins. )

RMS MX custom intake
( Our intake sits below the air box cover and stays quiet much like the stock intake setup, but it does not clog up with snow.

Seat Concepts seat
( We have the stock Yamaha seat pan recovered and re-foamed to give you a plusher seat and the ability to hold you in place. We did try the Acerbis replacement seat on the Hulk this season and found it to be to slick and it did not hold you in the correct position like the Seat Concepts unit did. )

ThermoBob thermostat
( Anytime the snow is deep enough to spray up on the engine it is trying to cool the engine temperatures down to a level that is colder than what a bike should run. In a test with a 1/2 mi. loop in 8" of fresh powder a bike with no thermostat would only get above 180deg. if it sat and idled for 30 min. and would run through the snow at 90deg. That is way to cold for a 4stroke. With a ThermoBob installed it would get to 180 in 10 min. of idling and run through the snow at 115deg. When the engine jacket was installed with the ThermoBob the bike would stay at 180deg. the entire time. Thermostats and engine blankets are a must for bikes in snow. )

PST engine jacket
( After full testing we are very happy with the results these units give us. They are easy to use and can be rolled down when the temperatures get warmer. and even removed all together for your April and May riding. )

Earth X battery
( We have been selling this battery for 4 seasons now and the reliability of it and its ability to start the bikes in sub zero temperatures is outstanding!! )

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Hulk review:

We used a 2016 CMX BK 129 for the kit on the hulk, but went through it completely and updating much of it to 2017 specs. First was pulling the drive shafts and sending them back to CMX to have them machined and replace the drive bearings on them. Then we replaced the 2016 MaxTrak with the new 2017 MaxTrak II, and updated the belt drive with the reverse idler setup and cover to allow more room for your heal on the belt side. We also added the new rear bumper for the tail of the tunnel, along with the RotoPak gas can mount and can. We also got rid of the twin ski front end and installed a Yeti front spindle and ski. It is now a 2017 except for the the shocks.

The things that make CMX great only got better with the new track. The flotation is awesome, the ability to have fun with the bike is like no other and is still a standout!!! The 129 transfers even more power to the snow than the 120, and is even more playful with the throttle. The MaxTrak II is a big improvement over the MaxTrak. It bites the hard pack even better and has all the flotation you could want. We love having the ability to pick the front ski off the snow with the throttle and create the weight transfer to the rear skid. It can be so much "snow bike fun"!!! The other side of the coin is that: you have to ride it like a dirt bike. If you are tired when you come up to a steep up hill and do not stand up on the pegs, the front end will pull up and loop out making you crash. If you are on your game and standing on the foot pegs, riding it like a dirt bike, it is very controllable on steep up hills. This gets even worse on big powered machines. We took this system off the Hulk and put it on the Ferrari race bike that put out 30 more HP than the Hulk. By the time we adjusted the suspension to control the wheelie to some degree, it was so stiff, it would buck you off in the woops. So the system went back on the stock powered machine and life was good again.

The reliability of the system was great all season. We even hit a 12" steel post with this kit and destroyed the side of it. After a little wait on parts we were able to put it all back together with no problems. The bolt together design of the system makes repairs super easy!!!!

The only design flaw of this system is that the brake is on the jack shaft. We had a belt get loose because we had not done the long bolt update to the belt tension-er and it loosened up on a hard full throttle bounce and stripped the teeth off the the belt. No problem, we carry a spare. We installed the spare that we had zip tied to the frame of the system. It possibly was kinked to tightly in storage an failed in 1mi. We then had to tow the bike back. With no belt, we had no brakes. We had to drop the bike on steep down hills and we even had a pile up with the tow bike because we couldn't stop. We would have been better riding back to camp to get another belt.

So many riders this season had great compliments on the ski pressure and how playful it was compared to there Timbersleds that had some ski push in the powder. The ski pressure can be stuck like glue when landing into a technical turn, then on the gas and pulls away with light pressure. It is a great combination of bite and maneuverability. With the system using the Yeti front end and ski, it has excellent manners on and off the trails. The CMX BK still feels like it has more suspension than a Timbersled even though it does not use a third shock. The feel of this suspension with a rubber bushing solid strut rod is amazing. We love the CMX BK for the "I want something better than a Timbersled but don't want to spend maga bucks for it." The CMX BK was $7295 for the 2017 season.

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Thor Review:

Stock 2017 Camso DTS 129.

We saw that the DTS was UGLY!!! Our custom RMS MX graphics sure helped its curb appeal.

The riders this season felt that the value of this system put it in line with the Timbersled kits for the performance verses the money spent.

The front ski takes some getting use to, but will preform quite similar to a Timbersled ski. It has some push and ill manners compared to the Yeti ski. The rear suspension in the system leaves a lot on the table. There is not much spring adjustment, and no adjustable dampening.

The cargo area is built in and you do not need to buy anything but two ratchet straps to hold in the gas can we sell and the cargo bags.

The mono rail skid and track are the huge standouts on this system. Having a track that has a full 2.5" deep paddle all the way out to the edges and moves so much more snow is a big plus. It will out climb all of the other systems on a deep day. This system just moves that much more snow. The mono center rail allows the track to bend and flex around the single center hyfax on the trail giving it the side to side roll you are after on the hard pack. Some riders even asked if this bike had motor mods because of the way the track moved the snow with such ease.

The chains are super easy to adjust and great to maintain. The only down fall is the track drive chain is kind of hard to get the chain lube to.

This system is value priced and delivers a good system for the money. It is HEAVY, the front ski could be better, and the rear suspension leaves a lot to be desired, but for the money it is in a position to give Timbersled Raw a run for their business in the cheep market. Camso's customer service and warranty department is great to deal with and parts are shipped fast to help the customers. Camso even published TSB's for corrections that were need for two different issues that were found in the field. As a dealer this was very proactive. All in all, it rides well, the track is great, and you can not get better performance in this price range. The Camso DTS 129 was $4799 for the 2017 season.

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If you are enjoying all of the time and effort we put into these reviews and bikes, please give us a call. We carry all the accessories you need for any snow bike you are building. Thank your business!!!!
 
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Wow, thanks for this excellent info!
I am picking up a 2018 YF450F soon and was wondering if you have any info, advice on building it for snow?
I ride a lot of mountain woods trail, occasional MX track but looking for top power on the snow.
My current bike I'm coming off of is a 2010 KTM 450 XCW SIX DAYS

Do you recommend the FX over the F?


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Just picked up my 2018 YZ450F

Wow, thanks for this excellent info!
I am picking up a 2018 YF450F soon and was wondering if you have any info, advice on building it for snow?
I ride a lot of mountain woods trail, occasional MX track but looking for top power on the snow.
My current bike I'm coming off of is a 2010 KTM 450 XCW SIX DAYS

Do you recommend the FX over the F?


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I am new to snow biking like you but rode both the F and FX. I bought the new 18 F because mainly the close ratio trans and more power then the FX and of course e-start on both bikes. Stay with what direction you are going! The bike is well worth the wait! I am really happy with the dirt riding feel and smooth delivery of the power. So glad I got mine so far. Only 1 good ride so far too. I am installing the Timbersled Aro 120LE with TSS. :eyebrows:
 
Yes, give us a call for everything you will need for your build.
We sell you the right accessories the first time that actually work on your snow MX application.

I have always preferred the F power and transmission over the FX, but we also like the easy button!!! The FX has done great for us, but the F has had more snap, due to the weight of the flywheel on the FX. Now for 2018 we will have it all in one bike!!!!


Wow, thanks for this excellent info!
I am picking up a 2018 YF450F soon and was wondering if you have any info, advice on building it for snow?
I ride a lot of mountain woods trail, occasional MX track but looking for top power on the snow.
My current bike I'm coming off of is a 2010 KTM 450 XCW SIX DAYS

Do you recommend the FX over the F?


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This next segment will dedicated to the high performance build for this year. It is a 2016 Yamaha YZ450FX with a very special Yeti 129 Robbie Madison edition.

We will call this one Robbie Madison.

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We will start by installing all of the regular RMS MX accessories like the bikes above, but we were not able to use our air intake on this highly modified motor. Our intake would not breathe well enough under the stock air box so we had to install a CR Racing intake that came up through the air box and delivered air flow this monster needed. We hated to add the noise of an exposed intake, but it did the trick. We did have a few hard hits throughout the year that through the rider forward on the saddle and knocked the filter element off of the riser. It was easy to loosen up the hose clamp and put it back on. I would prefer this situation, than something that is solid mounted and it racks you.

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Now on to the fun stuff: We wanted the FX to have more snap like its brother the F. So we decided to go full bore with all of the go fast goodies.

GYTR ported head w/ cams
GYTR 14:1 Piston
GYTR light weight clutch basket and pressure plate
FMF full head to tail titanium exhaust

The motor build is straight forward. You do have to split the cases to install the new oil sprayer. Once it was up and running we adjusted the fuel setting a few times to get the fueling where we wanted it. We were able to run 91 octane pump gas at our altitude of 8K- 13k. We did find that the bike would not start on the button unless you were holding the throttle just right. It would kick start every time. The GYTR cams have a lot of overlap and lift. The YZ450F cams are hotter than the FX cams, and slightly different than the GYTR cams. We gave them a shot and they started with ease on the button, and did not take any noticeable power out of the top end. We loved the added power and the quick rev of this engine package. It was as snappy as a F and had more top end power. We have built many big bores and such in the past, but are heading back to stock 450 kind of bores to keep the high revving 1/2-WOT snow bike fun kind of hit. The big bores seem to be lazy in comparison. We were so impressed with this bikes power it became our cross country race bike this year. We competed in both of the MSSR cross country races this year and finished with a 2nd and 3rd place finish. Not to shabby for a 44 year old dude!!

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We coupled this beast to a 2017 Yeti 129 special edition Robbie Madison. The Robbie is unique due to the fact that it uses a reinforced tunnel, dual Raptor remote reservoir shocks, RRS third shock, all titanium shafts and drivers, custom anodized rails, reactor arms, drivers, a wrap for the bike, it also comes with the gas can rack, cargo rack, all factory installed, and the freewheel kit to make it so easy moving this thing around.

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We never dreamed how great the 129 Yeti was until we rode it!!! We have always loved the 120 for a 190lb. rider, but what the heck, lets try a 129. You could not feel the difference in length between the 120 and 129 in the trees, but you could tell a difference in flotation in fresh powder. The weight of the Yeti was also a stand out. We were able to push it harder than any other bike this year. One word of caution; The Yeti system is FULLY adjustable. If you buy it and just slap it on, it may not perform quite like ours. We put much more time into designing the right set up for our customers. An Indy car is not built and goes out and wins races. It is put through weeks of testing to achieve the correct set up. If you purchase your Yeti from us here at Rocky Mountain Snow MX you will get our set up.


When you are looking at snow bike systems, a Yeti is kind of like a Ferrari. You'v heard of it, you know it's great, you may have never seen one up close. Then comes the day when you pony up and afford the best. It at that point that you wish you had done it years ago. The Yeti is by far the top performer in the snow bike world. From the fit and finish, to the attention to detail, this custom made work of snow bike art is the best money can buy.


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The Super Hero's are all shined up and at the Denver Snow Expo this weekend. Come out and see them in person.


ROCKY Mountain Snowmobile EXPO
Oct 7 - Oct 8 · 4655 HUMBOLDT ST, DENVER, CO 8021

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Hopefully you got your money back on those banners.


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Why do you say that? Yeti dealers are still Yeti dealers. The brand is still strong and the brand name is staying. It's no different than the Klim purchase. Klim stayed Klim. Yeti will stay Yeti.
 
It's now time for the weigh in.

All weights were taken with the stock fuel tank completely full of gas, and the straps on the foot pegs in the same position. Take notice of how the attitude of the bikes are different hanging from the straps.





Wonder Woman

2017 Yamaha YZ250 2-stroke 2017 Yeti Freeride 120 - 265lbs.



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Robbie Madison

2016 Yamaha YZ450FX 2017 Yeti SE Robbie Madison 129 - 312lbs.





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Hulk

2017 Yamaha YZ450FX 2017 CMX BK 129 - 321lbs.





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Superman

2015 Yamaha YZ450F Aerocharger 2017 CMX BK 120 - 336lbs.





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Thor

2017 Yamaha YZ450FX 2017 CMX BK 129 - 345lbs.




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Just for reference, this is how a dirt bike hangs:




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It's now time for the weigh in.

All weights were taken with the stock fuel tank completely full of gas, and the straps on the foot pegs in the same position. Take notice of how the attitude of the bikes are different hanging from the straps.





Wonder Woman

2017 Yamaha YZ250 2-stroke 2017 Yeti Freeride 120 - 265lbs.



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Robbie Madison

2016 Yamaha YZ450FX 2017 Yeti SE Robbie Madison 129 - 312lbs.





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Hulk

2017 Yamaha YZ450FX 2017 CMX BK 129 - 321lbs.





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Superman

2015 Yamaha YZ450F Aerocharger 2017 CMX BK 120 - 336lbs.





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Thor

2017 Yamaha YZ450FX 2017 CMX BK 129 - 345lbs.




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Just for reference, this is how a dirt bike hangs:




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great info . Just hung the Factory edition SXF 450 KTM dry and it 222, that's a huge savings from the jap bikes.
 
Since we are building the 2018 Super Heros. I thought I would bring back the last few years to the top of the forum.
 
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