bored's CRF50 build

[borednstreched]

I picked up a 2012 CRF50 clone, fresh off of break-in.
its a emissions model, it had a filtered crank breather tied into the air filter. a pcv/erg valve of some sort with 2 hoses hooked to it, 1 hose going to a nipple on the intake mani and the other goes to a nipple on the head, and a filter coming off of it also. a catalitic convertor.

i deleted the emissions stuff, polished out all the chrome and aluminum, took off the horrible stock graphics, relocated kill switch, gripper seat, flipped brake lever to clutch side(semi-auto), slime tubes, scott widow grips.

i picked this up for me to put around the alley on from time to time, and for the little man so he can go riding with us.
i also plan on getting a used klx110, big wheel xr70, ttr90-110 or a brand new ssr125/pitster125 for myself, so i can race around with him. i never should have traded my 04 kdx50 for that 93 cr250r.



it runs great, good power. i switched the stock ngk a7tc for a ngk-R plug gapped at 0.30. i weigh 250 and it gets me up to 35-40mph pretty easy.

thumb throttle, exhaust, bars, air filter are going to be the first upgrades were going to do. once i have that stuff done ill get graphics, carb, foot pegs, rear shock, 12" front wheel/hydro brake.

comments welcome, anyone have experience with them?

 

[blasterBruce]

Clean little pit bike ! , My nephew has the Yamaha 50 With the 88cc BBK and Gytr Pipe and that thing screams to be so small !

 

[borednstreched]

i got the throttle switched to a thumb throttle a buddy had laying around from a taotao 250, oddly enough it fixed the deadspot, and pulls more topend rpms now. kinda weird, must have been a issue with the old cable or twist.
i also spread the foot pegs so they are a little fatter, more area for your foot. and bent the kickstart to give better leg clearance/easier starts.

switched the stock crap strut out for a 11inch unit with a 300lb spring. its a tad stiffer than i wanted, but now it accelerates much harder and turns agressively due to it having almost no weight transfer, it puts all the power down now.it scratches every gear when shifting if youve got it at half throttle or more. ill change the strut back out when he starts riding it by himself and ive bought a 110-125cc for my self.

i cant decide on a exhaust. a ebay china cheapy, power-d perimeter exhaust, evo big gun, fmf pc4. anyone have any input for these exhausts?

 

[89blaster89]

get a fmf!! and wow thumb on a dirtbike thats odd but cool. for graphics a oldschool honda emblem would be sweet

 

[borednstreched]

i ended up making a lexan heat shield as the stock metal one did not do its job. i got a correct spring for the rear, rides like its on air now. i made a tilt bracket for the stock bars to get them out of my knees. i put 2 inch spacers and longer bolts on top of the forks, giving it more ground clearance in front, it also got the front tire away from the engine. ill be making new footpegs soon too.

 

[mud runner]

if it was me i would leave the stock exaust and just take the baffle out

 

[borednstreched]

ya i though about that, but all thats gonna do is give me more sound and a little flow. the reason i want a new exhaust is so i can get rid of the tiny catalitic converter in the header pipe, i dont want more sound out of the exhaust. i want power and flow.

 

[mud runner]

ok well i sugest a fmf

 

[Burke]

All the aftermarket exhausts are going to be loud on a 50... you can cut the screen out of your stock exhaust, and I don't remember if it was my 50 or my 110 that had a washer welded into the head to restrict flow. I believe it was the 110, but worth looking in the header for that.

My 50 has a TB 88 kit, TB rev box, FMF factory 4.1 pipe, CRF 70 forks, .50 cal +2 swingarm, I don't recall the shock on it, 24mm carb, and I ported the head, and a manual clutch... it is actually kind of scary to ride at the top of 3rd gear now. 58mph according to my Garmin!

 

[borednstreched]

^hell ya thats what im looking for.

 

[borednstreched]

polished all the fins on the head to a mirror finish. i put chrome pegs on the back, its a easier pivot point for your feet when your trying to ride wheelies or stunt. i keep ripping tubes in the back tire(had the same isue with the kdx50). i have a set of aluminum mag rims 14x3 front and 10x6 back with nice agressive street tires. they fit just barely, but they make the handling super touchy and hard to predict especially on gravel and dirt. pics today after i clean it up.

 

[borednstreched]

pics were in the shade so the fins dont look very bright.