yz426/400ex build

[hskers82]

Here is my hybred I am in the middle of building.YZ426 with wiseco 13:1 piston and yfz450 exhaust cam,burgard +2 a arms,lonestar stem,jansen racing radiator,g force +2 axle,aafco front shocks,450r rear shock,silver maier race cut plastic,quad tech scooped hood,shortened hmf slip-on

[hskers82]

http://s111.photobucket.com/albums/n143/hskers82/?sc=1&addtype=local

[ss440ex]

Very nice job!!
I like that color blue.
Do you have it running yet?

[hskers82]

No I just started putting it together today.Yeah that Candy Blue really comes to life in the sun.Thanks again Al for all the help

[hskers82]

pic 1

[hskers82]

pic 2

[hskers82]

pic 3

[hskers82]

pic 4

[hskers82]

Still not wired up,exhaust needs finished and oil and anti freeze lines need hooked up and a few other little things.I just put the wheels and plastic on to see how it would look

[2muchquad]

Looks good,did you have to fab your own lower front motor mounts?What did you use on the swingarm pivot to take up the slack in the rear motor mount?I have a yz426 mx bike and a 400ex chassis just sitting,hmmm,,,:devil:

[hskers82]

I bought a conversion kit from from a member on here(ss440ex) and it had all of the mounts and spacers.All I had to do was weld the brackets in place.I also bought the oil tank from ss440ex.His kits and oil tanks are top notch

[ss440ex]

Originally posted by 2muchquad
Looks good,did you have to fab your own lower front motor mounts?What did you use on the swingarm pivot to take up the slack in the rear motor mount?I have a yz426 mx bike and a 400ex chassis just sitting,hmmm,,,:devil:


I have two sets of front polished aluminum mounting horns and rear engine bushing and spacer left over if interested!!!

No longer doing the kits.

Cheap...Let me know.

[woodsracer144]

how hardwas it? i want something different and something with alot of power, i know the 426 puts out alot or there wouldnt be somany people doing it,
buy im 15 and i have a blaster and a extra chassie and was gonna strech it so it would fit right in buy mu shop teacher woulnt let me so im gonna try it on a 400ex i think, how hard is? does it take alot of time? does it cost much? what year of motor do you have? are some years better than others? thanks!
peyton m.

[hskers82]

It was not hard at all.You will have to know how to weld and you have to cut part of the frme(bath tub it ) so the carb intake will clear.If you want to get in depth info on this type of build get ahold of ss440ex on here.I bought my kit,oil tank, and air box from him.He has alot of knowledge on these builds and he might still have some conversion kits left.The motor is an '01 and I don't know about any problems for any of the years.

[woodsracer144]

ok thanks!
im thinkin about doin one what do you all have to weld?

[hskers82]

the upper and lower motor mounts,and the place that needs to get "bath tubbed" and you will want to gussett the frame

[woodsracer144]

how did you rune the boot from the air filter to the carb? i sayw in th bigger pics that it was a little close to run that tube.
thanks! where did oyu ahve to cut beside the front motor mounts? do you take mounts on the bike chassie? thanks!

[woodsracer144]

know of any one that welds really good and knows how to reinforce it, and theres not gonna be alot, im only 15 and i dont have a wire feed, but i have a ARK(sp?) welder, but i dont know how to do it, i havent really built any thing becasue ive only have done one frame transfer, thanks!

[Toadz400]

Originally posted by woodsracer144
know of any one that welds really good and knows how to reinforce it, and theres not gonna be alot, im only 15 and i dont have a wire feed, but i have a ARK(sp?) welder, but i dont know how to do it, i havent really built any thing becasue ive only have done one frame transfer, thanks!

I'd probably wait until you're a little more experienced and you have the proper tools to get the job done. I would recommend welding with a TIG if possible, you get the cleanest, strongest welds with them.

[hskers82]

For the carb to air filter/box I used a radiator hose for a powerstroke diesel that ss440ex recommended.You don't cut the front motor mounts off,the conversion kit I bought had new front motor mounts that bolted onto the front mounts(on the frame).Like Toadz400 said if you don't have the experience in welding this really isn't a project you want to tackle.TIG welding makes a great looking weld compared to mig or arc.I used a mig on mine because that is all I have available to me.If you are really sure you want to do this project just check around local welding shops and have them weld everything for you.I don't know what your budget is for this type of project because having someone do the welding for you will cost a little more

[woodsracer144]

will you post closer picks of where you welded? then i might have a idea, i think that my shop teacher will let me weld it because im not cuting the frame and strechin out and all that , sho where you have to mod the ftame, does the rear motor mount bolt, where it runs through the back of the frame thregh the swinger through the back of the motor to the other side and its really long i think you know what i mean, i heard that the yz's if bigger or somthing like that,
thanks, do you mind me askin about how much you paided fot the motor? i think that i can get atleast 600 for the 400ex motor that i will have, and you use the oild tank on the 400 and put the raidator infront?

[woodsracer144]

how did you wire it?

[ss440ex]

Any help..

[ss440ex]

More help..

[woodsracer144]

wahts the one weld do? i take it you do it on both side? and do you have to cut and of the plastic for the intake? do you use the 426 wireing too of what?

[ss440ex]

The bath tub!!!

[woodsracer144]

ok on the thing about toadz400, about the weldin, i can weld, but i only have a ark welder, ijust wld alot better with the shorter arcs,

[hskers82]

I paid $700 for my 426 motor but it had 2 bent shift forks and the cases had to be split.While it was apart I did a complete rebuild,new crank bearings,connecting rod,13:1 wiseco piston so I have about $1100 in a motor that I know is now "new".I used the wiring harness from the 426 and all of the other electrical as well(cdi,coil).AL(ss440ex) showed in the pics of most of the welding that will need to be done.The "bath tub" with a gussett support under it(the support is there because you are cutting out some of the frame and only putting back about half of what you cut out).In another of his pics he shows the top motor mount that has to be fabricated and welded.The only welds that were not shown was the bottom motor mount and the radiator supports.I bought a custom oil tank from ss440ex but I have heard of guys using the stock 400 tank.I would show you pics of all of the welds on my bike but it is together and I'm not about to take it partially apart to take pics

[hskers82]

The swingarm bolt from the 400ex has a smaller diameter so you will have to have a sleeve for that and you also have to have a spacer to line the front sprocket up with the rear sprocket(the spacer will go on the swingarm bolt to move the motor over a little bit).I don't know the size of the sleeve or the spacer as they came with my conversion kit

[TWISTED DINLI]

Originally posted by hskers82
pic 1

Thats awesome. nice job.

[woodsracer144]

ok, you paif 700 for the whole bike and it had a crapy motor? i gound a motor on ebay that was 250 and it had 3 days, does any one els make the kits since ss400ex no longer makes the kits and hes sold out? thanks!

[hskers82]

I paid 700 just for the motor.It wasn't crappy it just had 2 bent shift forks.I decided to do the entire rebuild for piece of mind.I don't know of anyone that sells conversion kits

[woodsracer144]

ok i got the ok to make it! have you jumpwe that 426 yet or have you took her out yet? my friend said that theres motre to it than slapin the motor in fi you were goin down the highway, somethign about cornering,and wheelis, and how it is when it jumps. ss400esx have you jumped a 426 off and big jumps? like does it go one way or the other alot easyly? do you have to do much when you get the motor, like i tife in the woods alot so are the s stocks good enough?
what size pipe do you weld in for suport by the "bath tub"? and how did you cut out the bath tub? did you just use a grinder? does any one have pics of the tabs you put on got the raidator?(sp?) thanks! i have to have all the stuff ready to weld and be ready to cut when i bring it to class, so i have to get any of the metal i want bent in a study hall and come in to do it,

thanks for all the help!

[hskers82]

Mine is set up for flattrack racing so that is a no on the jumping.I have seen alot of other conversions on here with the 400ex frame and can't say if anyone has had any problem with jumping them.If you do build this bike and plan on doing alot of jumping I would strongly suggest marking/installing gussets

[markvette]

this is my son jumping his ex/yz hybrid. this is a tabletop that is over 100 feet long. we bought our front motor mounts and air filter box from ss400ex. the rest we did ourselves.

http://i114.photobucket.com/albums/n246/quaddad1958/100_1306.jpg[/IMG]

[woodsracer144]

i have 2 questions, markvett, do you have your frame reinforced? were are the weakest spot?

whats size of pipe did you weld in place under the tub cut? the bar or pipe you weld it what size do you put in?

what would be the cheapest way, to buy a frame and all the parts to make one, or buy a whole 400ex? im thinkin bout buyin just the frame and buy parts as i go or els im gonna have to sell my blaster to buy a near by 400, what do you think?
thanks!

[woodsracer144]

how big of a spacer do you put in to push the motor over to get it lined up? and you do need to put a small pipe in side the rear motor mount/swinger bolt right? thanks!

[woodsracer144]

ok i looked for mounts on eastcoastatv.com and i cant find any, i fout the exter for the kick starter but i couldnt find any mounts, any one know of any other places that make them?

[markvette]

we did not do the tub cut. we did it on our first frame and that was the first place it broke. the cross bar on the subframe has to be cut out though. we used a piece of 2" radiator hose from the carb to the filter box. it flattens out a little where the tub cut should be but we have had no problems with it. it seems to get enough air. dont remember on the spacer for the swing arm bolt or swing arm spacer. ss400ex provided them dimensions for us and i had a local machinest do them for us. our frame is fully gusseted, will see if i can find some pics of it.

Mark

[markvette]

foot peg area


http://i114.photobucket.com/albums/n246/quaddad1958/100_1139.jpg

[markvette]

frame


http://i114.photobucket.com/albums/n246/quaddad1958/100_1138.jpg[/IMG]

[markvette]

front of frame



http://i114.photobucket.com/albums/n246/quaddad1958/100_1137.jpg[/IMG]

[markvette]

custom oil tank i had built. i made a card board templete, bought the aluminum off ebay and a guy built it for me for $40. it goes in front and under the radiator


http://i114.photobucket.com/albums/n246/quaddad1958/100_1085.jpg[/IMG]

[markvette]

radiator and oil tank in frame



http://i114.photobucket.com/albums/n246/quaddad1958/100_1102.jpg[/IMG]

[ss440ex]

Originally posted by woodsracer144
how big of a spacer do you put in to push the motor over to get it lined up? and you do need to put a small pipe in side the rear motor mount/swinger bolt right? thanks!

Spacer is .230

Bushing is 2.915 long
.675 OD
.585 ID

I have a spacer I can give ya.
exhorsepower has a bushing he`ll maybe sell ya!

[woodsracer144]

"Spacer is .230

Bushing is 2.915 long
.675 OD
.585 ID"

whats the OD and the ID?
hey mark can you get pics of the carb job you did? thanks! do you still have the teplate of the oil tank? how much did it cost to make that,

whats the smallest amout of oil can you have in the oil tank for the dry slump?

whats the easyest way to do the tabs for the raidator? (sp?) thanks! im gonna see if i can pick up a cheap frame sometime this weekend! i might have all the welds done!
thanks again evey one!

[woodsracer144]

whats the bushing made of? plastic? i have metal caps on the end of my a-arms with ruber inside of them for a bushing,
thanks!

[DOHC]

Where did u get thos Aafco front shocks? website?

[hskers82]

I bought them off of ebay.You should be able to do a google search for aafco and find a number.They may/may not advertise atv shocks because they make most of their money building shocks for dirt track cars.