Electric start 2010 yz250f

[smokers4ever]

Ive been on the 2 strokes for a while and thinking about going back to a 250f but only way i want another 4 stroke is if its got a magic button. First problem is who wants a out dated looking Wr , had that problem with my yz250. So when our shop aquired a couple of brand new 09 wr250f and some brand new 2010 yz250f bikes to part out the wheels started turning . The project is to use the wr bottom end, a cylinder works 269 kit, the yz head ( since the top motor mount changed ) with hot cams , one of the new lithuim batterys and rework the entire wr harness to fit the yz. So far just setting the wr motor in the frame everthing looks like a go, Does any one know of any reason why i cant use the new head on cylinder works kit all on top of a wr bottom end.

[PitBikeNoob]

If I were you, just get a WR and do the wire mod thing that makes it run like a YZ, and just build up that engine. If you really want power and electric start, go with a KTM 350:smirk:

[Swede73]

WR/YZ conversion is very popular and easy. It is A LOT cheaper to convert a WR to a YZ than it is to convert a YZ to a WR. Get the WR!! You will not be disappointed

[PitBikeNoob]

Or just get the 350:smirk:

[William1]

The head will be fine on the barrel. You are on the right track with this project. Since you are going all out, get a Vortex (or similar) CDI for a WR.

[smokers4ever]

The two bikes where coming apart anyways for parts so if i make one just the way i want it, its the same price . There is no one cheaper than the other to convert, Everybody wants to ride the newest looking bike so why would i want the wr, Just looks out dated, plus wheres the fun in riding something everyone has. As for the ktm 350 yes ive drooled over them and want one but there are no discounted ktm bikes out there new. Bottom line is the ktm would cost me 8500 or better and i can built this bike for with big bore, cams, revalved suspension , big tank, stabilizer , and graphics for close to 6000. Most of the fun is just building it before i get to ride it anyways .

[smokers4ever]

Found a couple of differences between the new yz and wr cases today. Evidently the yz frame is nawworer than the wr. The Wr oil drain plug is right into the frame after mounted but luckily the cases are casted for the yz drain plug . So after some carefull thinking just drilled cases for the new style drain and taped it. Had to cut just a little off the old drain plug so it didnt plug my new hole but after everything was done all looked like it left the factory this way. Also looks like the newer oil tanks are about half the size of the old on . I think Yamaha just move the oil sight glass higher and carries more oil in the motor. Got the 269cc cylinder on, 2010 yz head and hot cams on, motor bolts right in no problems. Got the lithium battery mounted to seat base and cdi mount to a new bracket rivet to subframe in the airbox . Next going to just hang the wiring off the side and fire the motor up , after that going to get all electricals mounted and start acking at the wire harness . got to start ordering exhaust, oversize tank ,stabilizer and some misc since project looks like a complet GO!!!

[PitBikeNoob]

:0 wow that looks pretty sick. Nice work on the drain bolt. But how are you getting all these parts?

[mari0]

He said in his first post he works @ a motorcycle shop and their parting out some bikes

[Swede73]

I'm jealous now. Thanks jerk!! J/k take pics when you're done and tell us exactly what mods you had to do to make it work besides the ones you already listed

[smokers4ever]

Got the bike started today with all the wires just hanging on top the bike The plugs for the TPS on the carb and wire harness are not compatible ( using yz carb when i should have probably use the wr) . Wire are still color matched so i will just wire a new end on the harness. Order a DRD neutral switch cover to eleminat that wire, Dont need odometer , headlight, tail light or clutch saftey switch so going to start pulling the harness apart and cuting out the wires . Going to try to do away with kill switch and ignition button and just use a rocker type on/off switch from a ttr90. Does anyone know how the igntion button works. Its got 4 wires and not sure yet how to bypass and be able to cut the just off so not to run battery down

Ill try to get a pic tomarrow of the bulky harness before start cuttin

[brentn]

Nice work!!

I would think that the YZ suspension has much more potential if valved properly than the WR suspension for woods riding. Pretty sure that all the WR's are single chamber and valved for woods while the YZ's from 05/06+ are dual chamber and valved for MX/SX. Battery in the seat is a great idea btw!!!

[shrubitup]

Wow, I'd be really happy with a bone stock 2010 YZ250F. They're gorgeous bikes IMO.

[smokers4ever]

Ok unwraped the wire harness and started triming it down . Starting in the front, Have to keep the start button, Only reason for the projet, but two kill switches .Ones got to go. I did away with the push button ignition and replaced with a ttr90 on off rocker switch. Just using a sharp scribe type tool you can release the wires from the ends . two of the wires in the light switch just light it up and are not needed so moved the standard kill button end(one from the harness ) onto the wire that are need , then used the matching end from actual kill switch on the rocker switch so everything plugs up like the factory. Then removed the stock kill button wires complete from harness all the way back to pulling the plug out of the cdi. Un snapped the grey cdi wire( mode wire) from cdi then completely from the harness. It just runs down to the main ground. Tail light wire removed completely from the harness.( tail light has a 3 way plug that can be used elsewhere on harness to replace the male tps plug so it will then be compatable with the yz card.) Then headlight ground wire completely removed , the power for the light ties in the stator with the regulator so removed the power to light and directly conneted stator and regulator. Drd neutral switch replacement plug is on the way so completly removed this wire from the cdi to the switch. Then removed clutch saftey switch from harness but had to ground one of the wires inside harness to fool one of starter relays. Odometer wires removed all the way from the cdi. Ran out of time for the night , and about out of things i can throw away, Next will have to mount relays, regulator , route and extend wires.

[PitBikeNoob]

Damn dude lookin good.

[Ryanyzmx]

That is a sick bike. Really impressed with all the work you have put into it. Keep going and keep us posted.

[smokers4ever]

Left project tuesday and it start and everything was fine. started back on it today no no fire, I tried to put a stock harness back on it, starter and all stock switch , Nothing, Only thing i dont have two of is the cdi,

Any got a extra stock or aftermarket cdi they want to get ride of . pm me

[smokers4ever]

Never mind, figured out my firing problem, got to watch which wire i cut next time.

[smokers4ever]

Well got the harness trimed down and shortend. Removed the factory kill button, and use only a on off switch , replaced neutral switch with drd pug and remove that wire completly , removed all odometer , all of lights, removed so many saftey wires from the cdi i was able to put all the wire in two plugs instead of three. Mounted regulator to the cdi plate, and starter relay in small pocket in front of tank between radiators. few pics of wire on bike before i got them wraped, bike should be runable now , just time to start installing the woods goodies,

RELAY

stock harness

new harness

[Swede73]

Looks like a food fight at a spaghetti factory!! I hope you drew your own schematic for the bike. Are you going to put all of those wires in harnesses?