YZ426 Hybrid Dosn't pull as hard as my 440ex, HELP ME!!!

[Groves187]

Ok, So i just got my YZ426 together and took it out for its first ride today and it dosn't even feel like it pulls as hard as my 440ex did, Had it in 2nd gear and Cracked it and it would hardly pull the front tires off the ground. So i called up the guy i bought it from and he said it should pull my arms off, I put on a 40mm Lectron carb with no airbox (carb was off a YZ426 with similar engine mods). I did not try to tune the carb. I am running 16/38 gearing with 18" tires. What do you guys think could be my problem...

Thanks, Nick

[LT250Racer609]

you just cant go throwing a different carb. on it, and not jet it right and expect it to run in tip top shape...re-jet it and get back to us.

[Groves187]

I wasn't expecting it to run tip top shape, The jetting shouldn't be that far off as it starts good and dosn't bog or pop..

[ss440ex]

14 - 38 or 14 - 37 with 18" tires should work good.

[Groves187]

So do you think it could have somthing to do with my gearing then?

[matt250r21]

You are geared way high. Like stated before try 14/38 or 37, 36. Might also need to try a 13 tooth front sprocket on the dirt bike motor, the internal gear ratios are not really quad friendly. But that is just my opinion.

[Groves187]

Yeah, I am starting to think that its the jetting in the carb, When i start it and rev it, it wont even hit the rev limiter... and when i was riding it it wasn't hitting it there eather.... I wish i new how to jet the Lectron Carb....

[Groves187]

Well guys, i seam to have found my problem of why it dosn't pull very hard, It seams that mister Jeremy Gentry From Hot springs ArK. Sold me a YZ400 Hybrid and not a YZ426 like stated in the post that he had up! Would not recamend anyone and i mean anyone to do any kinda of Bussnes with him!! His name on here is twankee3 and his name is Jeremy Gentry from Hot Springs ARK. I dont care what he trys to tell anyone that he didn't rip me off, but unfortanitly he did! and it will be handled!

[hontrx265r]

I have no idea who that is but don't jump to conclusions. That motor could still be 426 if the cylinder was bored, or the crank was stroked. When I built my first hybrid someone did the same thing to me though and sold me a 400 motor. It still ran very very strong though so I still doubt your engine is running weak because of that, I think it would still walk all over a 440ex

[LT250Racer609]

wow that really really sucks...

He actually called me about 3 weeks ago about buying my 350R before I decided to get rid of the motor and make it a Hybrid. He was gonna drive up here to NY and buy it. Claimed he had "cash" in hand. Then we got talking and he asked me what quad I was gonna buy and I sent him the link to the Hybrid I wanted. He went behind my back and PMed the guy with the Hybrid saying he was gonna buy that off him when he told me our deal was pretty much closed. Anyways i was talking to the owner of the Hybrid also on the phone because if this "twankee" guy wasnt gonna buy his Hybrid, we were gonna trade quads...his Hybrid for my 350R...well the Twankee guy left the Hybrid guy hangin so he just ended up with throwing his Hybrid on ebay which is why im building my own right now...

Twankee also tried to trade me that "426" that you have no I said no to it. Then he told me how he had this insanly built YFZ450 that he wanted to trade....bla bla point is, hes a lier and +2 for doing no business with him!

[jrspawn]

That sucks about your deal man. But like someone posted, it might have a 426 bore/cylinder on it.

Even being a 400, it should still pull Very strong. They are a good stout running engine for sure. First thing i recomend doing is taking that lectron off. Get an FCR back on it and start from there. You woulnt miss the lectron one bit.

Thank you
Justin

[twankee3]

Originally posted by hontrx265r
I have no idea who that is but don't jump to conclusions. That motor could still be 426 if the cylinder was bored, or the crank was stroked. When I built my first hybrid someone did the same thing to me though and sold me a 400 motor. It still ran very very strong though so I still doubt your engine is running weak because of that, I think it would still walk all over a 440ex

no joke it is a 426 and it will walk all over a 440ex and alot of others. you just need the right carb a 39mm FCR with a 165 main. problem solved 400f is the best bottom end. in my opinion and alot of others opinions.............. but ride and set it up as you wish. just dont slander and profile me because you dont know alot about yz 4 stroke motors take that junk lectron off and do it right. but your first hybrid cool i can make a cool lil sig. 2 but that would be childish of me. tune your quad and ride it.

[800screws]

a 426 cylinder will fit on a yz400 bottom end...and either or should hit alot harder than a ex...get the fcr carb, i agree. throw a boyesen acc. pump cover and a extended fuel screw on it before u mount it. mine was almost close to stock jetting. i think a 170 main and a 42 or 45 pilot...

[Groves187]

yeah, the cylinder says 399cm3 on it, Talking about childing, How about you call me back or answer my phone calls like you said you would. So we can get this fixed!

And send me the 39MM FCR FLAT SLIDE I paid you for!!

[josborn]

You really need to mic. the piston, or the bore to be sure. When they bore the 400's out to 426, they don't change the casting on the outside. Regardless, put the 39mm FCR on it, and gear that thing either 14-38 or 14-37, and if its healthy, it will go.

[Oldsparky]

Originally posted by josborn
You really need to mic. the piston, or the bore to be sure. When they bore the 400's out to 426, they don't change the casting on the outside. Regardless, put the 39mm FCR on it, and gear that thing either 14-38 or 14-37, and if its healthy, it will go.

400fs get bored out all the time athena makes kits, and many other companies. I agree with whats said above 39mm Fcr 165 to 170 main. Ive had several hybrids even a 400f and the 426 ran around the same jetting.

[josborn]

I know they bore them. My point was that just because it says 399cm3 on the outside doesn't mean it hasn't change on the inside.