Fitting a 98 to 99 YZ motor in a Tri Z

**CHAINSAW** · 09-11-2004, 10:32 PM

and its highly unlikely a 4 stroke would fit into the frame. Relocating the gas tank wont work, unless its a drag race only machine. The tank will only hold a gallon, 1 1/2 at most when put up where a regular tank will go. If the frame is modded to accept the taller 4 stroke motor, well thats even less of a tank that would fit.

**370banshee** · 09-12-2004, 09:54 AM

merriman i'm sorry but putting a 4 poke into a tri-z would be like swapping 4cyls into corvettes. you can say what you want about how nice the new 4 strokes are but they way i look at it is this. it was made for a 2 stroke and that what should stay in it. tri-z's are made to be arm stretching ring dingin fast trikes. oh yeah who would wanna screw with valves, camshafts, timing chains. screw all that. darious squeeze that new YZ enigne into it then laugh at the new 4 stroke quad with your trike

**BigGreenMachine** · 09-12-2004, 02:34 PM

The new 4-pokes have lots of grunt, it would be like putting a V4 in your trike IMO but the size of the YZ450 motor makes it an awkward fit and who wants to mess with cam chains and valves anyway...

The YZ 250 and YZ450F make around 45 to 50 hp each and weigh close to the same. Personally I'd love to have a Kawasaki 450 fourstroke in my 85 Tecate or an 86 Tecate. Just because of the controlability of a fourstroke motor and contrary to what most sissies believe, cam and valve adjustments aren't that bad. Maybe someday...

**TimSr** · 09-12-2004, 03:07 PM

I think the idea of using a YZ 2 stroke motor is so you can drop it in with a minimum of welding and frame hacking. My interest in the YZ motors is simply as a replacement thats a little easier to find than a YTZ motor. I have yet to see the guy who has mastered using all the power a stock TriZ can deliver that runs properly, so Im not even interested for the power valve upgrade. I want to keep mine in operation as opposed to re-designing a whole new one. And, Im sorry, but those monster custom builds with an oversized, overweight, and overpowered motors are only good for one thing. They are useless for normal riding. Your also not going to find a lot of scrap motors from 450's laying around in the junkyard for a few hundred dollars, but even if you did, and managed to get it mounted, and build an exhaust, the stock TriZ would kill it everywhere but on a drag strip, and even there, its questionable. If you want a 4 stroke, Im pretty sure Honda built a pretty good one.

**BigGreenMachine** · 09-12-2004, 03:37 PM

I didn't mean to agree that a four stroke would be the best choice, just got carried away with ideas I want to try. A YZ motor, especially the 98 and up motors would be a great swap for the Tri-Z and if its only the pipe that would really pose an installization problem thats easy enough to solve by having a company like CT make you a custom pipe. As for lights there are kits available for the YZ that some Supermotard drivers buy to make their dirtbikes road legal.

**370banshee** · 09-12-2004, 08:09 PM

i think all of the guys in here with powervalve tri-z do drag race them i know thats what mines for

**Darius1502** · 09-13-2004, 04:19 PM

I don't want to 4 stroke motor in the Tri Z because as it was stated earlier the Tri Z is ring a ding two stroke 3 wheeler. Besides...in 2006 we probably wont have an more two strokes in production so I can do without the 4 strokes.

I will do the project but it may take some time since right now I pretty busy. The motor will be a 98 to 00 YZ 250 motor. I am exicted as heck about getting started but it will be a while.

I'll keep everyone posted. I can't believe that no one has done this. Can someone compare the cases of an 89 YZ 250 motor to the 98 motor.

Thanks,

**hondatrikesrule22** · 09-13-2004, 05:53 PM

I don't know...them 4-strokes are getting fast. I was watching OLN earlier, and there was a guy racing a 250 4-stroke with the 250 2-strokes, and he was kicking ass!

**Darius1502** · 09-13-2004, 06:39 PM

I have a YZ 400F and I can tell that while they are fast a 2 stroke 250 is much much more fun to ride.

**BigGreenMachine** · 09-13-2004, 08:04 PM

Hondatrike I hope you meant "450" fourstroke was kicking the two strokes ass cause no way will a 250 fourstroke be beating a 250 2-stroke.

**OldSchoolin86** · 09-13-2004, 09:14 PM

Originally Posted by hondatrikesrule22

I don't know...them 4-strokes are getting fast. I was watching OLN earlier, and there was a guy racing a 250 4-stroke with the 250 2-strokes, and he was kicking ass!

LOL! The people on the 2-strokes had to be really sad if that was the case!

**hondatrikesrule22** · 09-13-2004, 10:38 PM

Maybe the guy said it wrong, but I could have sworn he said 250.

**CHAINSAW** · 09-13-2004, 11:15 PM

with exception to the new 450 4 strokes, a good rule of thumb. It takes double the amount of cc in a 4 stroke, to match the power of 2 stroke. Thats not no rule or anything, there are exceptions, but a lot are like that. So 250cc 2 stroke is the same as a 500cc 4 stroke. 250cc 4 strokes, can usually get whopped by 125cc 2 strokes.
Like I said, its not gods honest truth, but most of the time its that way.

**370banshee** · 09-14-2004, 12:00 AM

yeah chainsaw thats the rule of thumb. except in the case of the new 450 quads like you said. i say long live 2 strokes. what real quads, trikes, and bikes really have as a heart a premix smoking arm stretching, hold the **edited** on kinda ride. damn i'm getting all excited just thinking bout it

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